From 8ffc556a977fb2a2e4a67b23ca53eaf9b06575e4 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 08:38:16 -0400
Subject: [PATCH 01/37] use insensitive key

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift   | 39 ++++++++++++++++++++++------
 test/swift/HeadersBuilderTests.swift | 12 +++++++++
 2 files changed, 43 insertions(+), 8 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 0217597bd0..73e06b56ba 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,14 +3,37 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  return name == "host" || kRestrictedPrefixes.contains { name.hasPrefix($0) }
+  return name.lowercased() == "host" || kRestrictedPrefixes.contains { name.lowercased().hasPrefix($0) }
 }
 
 /// Base builder class used to construct `Headers` instances.
 /// See `{Request|Response}HeadersBuilder` for usage.
 @objcMembers
 public class HeadersBuilder: NSObject {
-  private(set) var headers: [String: [String]]
+
+  struct CaseInsensitiveKey: Hashable {
+    let name: String
+    lazy var lowercasedName: String = { self.name.lowercased() }()
+
+    static func == (lhs: CaseInsensitiveKey, rhs: CaseInsensitiveKey) -> Bool {
+      var lhs = lhs, rhs = rhs
+      return lhs.lowercasedName == rhs.lowercasedName
+    }
+
+    func hash(into hasher: inout Hasher) -> Int {
+      hasher.combine(self.name.hashValue)
+      return hasher.finalize()
+    }
+  }
+
+  private(set) var _headers: [CaseInsensitiveKey: [String]]
+
+  var headers: [String: [String]] {
+    return Dictionary(uniqueKeysWithValues: _headers.map { key, value in
+    var k = key
+     return (k.lowercasedName, value) 
+     })
+  }
 
   /// Append a value to the header name.
   ///
@@ -24,7 +47,7 @@ public class HeadersBuilder: NSObject {
       return self
     }
 
-    self.headers[name, default: []].append(value)
+    self._headers[CaseInsensitiveKey(name: name), default: []].append(value)
     return self
   }
 
@@ -40,7 +63,7 @@ public class HeadersBuilder: NSObject {
       return self
     }
 
-    self.headers[name] = value
+    self._headers[CaseInsensitiveKey(name: name)] = value
     return self
   }
 
@@ -55,7 +78,7 @@ public class HeadersBuilder: NSObject {
       return self
     }
 
-    self.headers[name] = nil
+    self._headers[CaseInsensitiveKey(name: name)] = nil
     return self
   }
 
@@ -69,14 +92,14 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   func internalSet(name: String, value: [String]) -> Self {
-    self.headers[name] = value
+    self._headers[CaseInsensitiveKey(name: name)] = value
     return self
   }
 
   // Only explicitly implemented to work around a swiftinterface issue in Swift 5.1. This can be
   // removed once envoy is only built with Swift 5.2+
   public override init() {
-    self.headers = [:]
+    self._headers = [:]
     super.init()
   }
 
@@ -84,7 +107,7 @@ public class HeadersBuilder: NSObject {
   ///
   /// - parameter headers: The headers with which to start.
   required init(headers: [String: [String]]) {
-    self.headers = headers
+    self._headers = Dictionary(uniqueKeysWithValues: headers.map { key, value in (CaseInsensitiveKey(name: key), value) })
     super.init()
   }
 }
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index bf8990026b..129210d8ee 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -78,4 +78,16 @@ final class HeadersBuilderTests: XCTestCase {
     let headers2 = RequestHeadersBuilder(headers: ["x-foo": ["123"], "x-bar": ["abc"]]).build()
     XCTAssert(headers1 !== headers2)
   }
+
+  // func testInitializationIsCaseSensitiveButDoesIgnoresKeysCasingWhenLookingForDuplicates() {
+  //   let headers = HeadersBuilder(headers: ["fOo": ["abc"], "foo": ["123"]])
+  //   XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers)
+  // }
+  
+  func testInitializationIsCaseInsensitiveOperation() {
+    let headers = HeadersBuilder(headers: ["foo": ["123"], "fOo": ["abc"]])
+    headers.set(name: "fOo", value: ["abd"])
+    headers.set(name: "foo", value: ["123"])
+    XCTAssertEqual(["foo": ["abc", "123"]], headers.headers)
+  }
 }

From c3c90155c4e73fbaf7372c0a54a0cfb5cba8bbf2 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 10:04:37 -0400
Subject: [PATCH 02/37] Make HeadersBuilder case insensitive

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift   | 73 +++++++++++++++++++---------
 test/swift/HeadersBuilderTests.swift | 38 ++++++++++-----
 2 files changed, 77 insertions(+), 34 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 73e06b56ba..e2ade1d1ba 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,35 +3,42 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  return name.lowercased() == "host" || kRestrictedPrefixes.contains { name.lowercased().hasPrefix($0) }
+  return name == "host" || kRestrictedPrefixes.contains { name.lowercased().hasPrefix($0) }
 }
 
 /// Base builder class used to construct `Headers` instances.
+/// It preserves the original casing of headers and enforces a case
+/// insensitive look up and setting of headers.
 /// See `{Request|Response}HeadersBuilder` for usage.
 @objcMembers
 public class HeadersBuilder: NSObject {
+  struct KeyValuesPair {
+    private(set) var key: String
+    private(set) var values: [String]
 
-  struct CaseInsensitiveKey: Hashable {
-    let name: String
-    lazy var lowercasedName: String = { self.name.lowercased() }()
+    init(key: String, values: [String] = []) {
+      self.key = key
+      self.values = values
+    }
+
+    mutating func appendValue(_ value: String) {
+      self.values.append(value)
+    }
 
-    static func == (lhs: CaseInsensitiveKey, rhs: CaseInsensitiveKey) -> Bool {
-      var lhs = lhs, rhs = rhs
-      return lhs.lowercasedName == rhs.lowercasedName
+    mutating func appendValues(_ values: [String]) {
+      self.values.append(contentsOf: values)
     }
 
-    func hash(into hasher: inout Hasher) -> Int {
-      hasher.combine(self.name.hashValue)
-      return hasher.finalize()
+    mutating func setValue(_ value: String) {
+      self.values = [value]
     }
   }
 
-  private(set) var _headers: [CaseInsensitiveKey: [String]]
+  private var _headers: [String: KeyValuesPair]
 
   var headers: [String: [String]] {
-    return Dictionary(uniqueKeysWithValues: _headers.map { key, value in
-    var k = key
-     return (k.lowercasedName, value) 
+    return Dictionary(uniqueKeysWithValues: _headers.map { _, value in
+      return (value.key, value.values) 
      })
   }
 
@@ -43,11 +50,12 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func add(name: String, value: String) -> Self {
-    if isRestrictedHeader(name: name) {
+    let lowercasedName = name.lowercased()
+    if isRestrictedHeader(name: lowercasedName) {
       return self
     }
 
-    self._headers[CaseInsensitiveKey(name: name), default: []].append(value)
+    self._headers[lowercasedName, default: KeyValuesPair(key: name)].appendValue(value)
     return self
   }
 
@@ -59,11 +67,12 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func set(name: String, value: [String]) -> Self {
-    if isRestrictedHeader(name: name) {
+    let lowercasedName = name.lowercased()
+    if isRestrictedHeader(name: lowercasedName) {
       return self
     }
 
-    self._headers[CaseInsensitiveKey(name: name)] = value
+    self._headers[lowercasedName] = KeyValuesPair(key: name, values: value)
     return self
   }
 
@@ -74,11 +83,12 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func remove(name: String) -> Self {
-    if isRestrictedHeader(name: name) {
+    let lowercasedName = name.lowercased()
+    if isRestrictedHeader(name: lowercasedName) {
       return self
     }
 
-    self._headers[CaseInsensitiveKey(name: name)] = nil
+    self._headers[lowercasedName] = nil
     return self
   }
 
@@ -92,7 +102,7 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   func internalSet(name: String, value: [String]) -> Self {
-    self._headers[CaseInsensitiveKey(name: name)] = value
+    self._headers[name.lowercased()] = KeyValuesPair(key: name, values: value)
     return self
   }
 
@@ -107,7 +117,26 @@ public class HeadersBuilder: NSObject {
   ///
   /// - parameter headers: The headers with which to start.
   required init(headers: [String: [String]]) {
-    self._headers = Dictionary(uniqueKeysWithValues: headers.map { key, value in (CaseInsensitiveKey(name: key), value) })
+    var processedHeaders = [String: KeyValuesPair]()
+    for (name, values) in headers {
+      let lowercasedName = name.lowercased()
+      /// Dictionaries in Swift are unordered collections. We process headers with keys
+      /// that are the same when lowercased in an alphabetical order to avoid a situation 
+      /// in which the result of the initialization is underministic i.e., we want
+      /// "[A: ["1"]", "a: ["2"]]" headers to be always converted to ["A": ["1", "2"]] and
+      /// never to "a": ["2", "1"].
+      ///
+      /// If a given header name already exists in the processed headers map, check
+      /// if the currently processed header name is before the existing header name as
+      /// determined by an alphabetical order.
+      if let existing = processedHeaders[lowercasedName], existing.key > name {
+        processedHeaders[lowercasedName] = KeyValuesPair(key: name, values: values + existing.values)
+      } else {
+        processedHeaders[lowercasedName, default: KeyValuesPair(key: name)].appendValues(values)
+      }
+    }
+
+    self._headers = processedHeaders
     super.init()
   }
 }
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index 129210d8ee..08c1540809 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -40,6 +40,32 @@ final class HeadersBuilderTests: XCTestCase {
     XCTAssertEqual(["x-foo": ["abc"]], headers)
   }
 
+  func testInitializationIsCaseInsensitivePreservesCasingAndProcessesConflictingHeadersInAlphabeticalOrder() {
+    let headers = HeadersBuilder(headers: ["a": ["456"], "A": ["123"]])
+    XCTAssertEqual(["A": ["123", "456"]], headers.headers)
+  }
+
+  func testAddingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
+    let headers = HeadersBuilder(headers: [:])
+    headers.add(name: "fOo", value: "abc")
+    headers.add(name: "foo", value: "123")
+    XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers)
+  }
+
+  func testSettingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
+    let headers = HeadersBuilder(headers: [:])
+    headers.set(name: "foo", value: ["123"])
+    headers.set(name: "fOo", value: ["abc"])
+    XCTAssertEqual(["fOo": ["abc"]], headers.headers) 
+  }
+
+  func testRemovingHeaderIsCaseInsensitive() {
+    let headers = HeadersBuilder(headers: [:])
+    headers.set(name: "foo", value: ["123"])
+    headers.remove(name: "fOo")
+    XCTAssertEqual([:], headers.headers) 
+  }
+
   func testRestrictedHeadersAreNotSettable() {
     let headers = RequestHeadersBuilder(method: .get, authority: "example.com", path: "/")
       .add(name: "host", value: "example.com")
@@ -78,16 +104,4 @@ final class HeadersBuilderTests: XCTestCase {
     let headers2 = RequestHeadersBuilder(headers: ["x-foo": ["123"], "x-bar": ["abc"]]).build()
     XCTAssert(headers1 !== headers2)
   }
-
-  // func testInitializationIsCaseSensitiveButDoesIgnoresKeysCasingWhenLookingForDuplicates() {
-  //   let headers = HeadersBuilder(headers: ["fOo": ["abc"], "foo": ["123"]])
-  //   XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers)
-  // }
-  
-  func testInitializationIsCaseInsensitiveOperation() {
-    let headers = HeadersBuilder(headers: ["foo": ["123"], "fOo": ["abc"]])
-    headers.set(name: "fOo", value: ["abd"])
-    headers.set(name: "foo", value: ["123"])
-    XCTAssertEqual(["foo": ["abc", "123"]], headers.headers)
-  }
 }

From 8137392332fa1d210192043331d750c30801e6bd Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 10:07:07 -0400
Subject: [PATCH 03/37] remove unnecessary call

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index e2ade1d1ba..188ff8d431 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,7 +3,7 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  return name == "host" || kRestrictedPrefixes.contains { name.lowercased().hasPrefix($0) }
+  return name == "host" || kRestrictedPrefixes.contains { name.hasPrefix($0) }
 }
 
 /// Base builder class used to construct `Headers` instances.

From 15f722b222cb7b1638074d700abc1e357d100f9e Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 10:56:49 -0400
Subject: [PATCH 04/37] Update code

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift             | 11 ++++++-----
 library/swift/RequestHeadersBuilder.swift      |  2 +-
 library/swift/RequestTrailersBuilder.swift     |  2 +-
 library/swift/ResponseHeadersBuilder.swift     |  2 +-
 library/swift/ResponseTrailersBuilder.swift    |  2 +-
 .../swift/grpc/GRPCRequestHeadersBuilder.swift |  2 +-
 test/swift/HeadersBuilderTests.swift           | 18 +++++++++---------
 7 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 188ff8d431..7c359d2c5d 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -36,10 +36,10 @@ public class HeadersBuilder: NSObject {
 
   private var _headers: [String: KeyValuesPair]
 
-  var headers: [String: [String]] {
-    return Dictionary(uniqueKeysWithValues: _headers.map { _, value in
-      return (value.key, value.values) 
-     })
+  func headers() -> [String: [String]] {
+    return Dictionary(uniqueKeysWithValues: self._headers.map { _, value in
+        return (value.key, value.values) 
+    })
   }
 
   /// Append a value to the header name.
@@ -117,6 +117,7 @@ public class HeadersBuilder: NSObject {
   ///
   /// - parameter headers: The headers with which to start.
   required init(headers: [String: [String]]) {
+
     var processedHeaders = [String: KeyValuesPair]()
     for (name, values) in headers {
       let lowercasedName = name.lowercased()
@@ -145,6 +146,6 @@ public class HeadersBuilder: NSObject {
 
 extension HeadersBuilder {
   public override func isEqual(_ object: Any?) -> Bool {
-    return (object as? Self)?.headers == self.headers
+    return (object as? Self)?.headers() == self.headers()
   }
 }
diff --git a/library/swift/RequestHeadersBuilder.swift b/library/swift/RequestHeadersBuilder.swift
index d36a1b318d..8b4d64cde7 100644
--- a/library/swift/RequestHeadersBuilder.swift
+++ b/library/swift/RequestHeadersBuilder.swift
@@ -52,6 +52,6 @@ public final class RequestHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of request headers.
   public func build() -> RequestHeaders {
-    return RequestHeaders(headers: self.headers)
+    return RequestHeaders(headers: self.headers())
   }
 }
diff --git a/library/swift/RequestTrailersBuilder.swift b/library/swift/RequestTrailersBuilder.swift
index b5b855aa00..a521549f2c 100644
--- a/library/swift/RequestTrailersBuilder.swift
+++ b/library/swift/RequestTrailersBuilder.swift
@@ -12,6 +12,6 @@ public final class RequestTrailersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of request trailers.
   public func build() -> RequestTrailers {
-    return RequestTrailers(headers: self.headers)
+    return RequestTrailers(headers: self.headers())
   }
 }
diff --git a/library/swift/ResponseHeadersBuilder.swift b/library/swift/ResponseHeadersBuilder.swift
index 56c213d191..970a75ec93 100644
--- a/library/swift/ResponseHeadersBuilder.swift
+++ b/library/swift/ResponseHeadersBuilder.swift
@@ -23,6 +23,6 @@ public final class ResponseHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of response headers.
   public func build() -> ResponseHeaders {
-    return ResponseHeaders(headers: self.headers)
+    return ResponseHeaders(headers: self.headers())
   }
 }
diff --git a/library/swift/ResponseTrailersBuilder.swift b/library/swift/ResponseTrailersBuilder.swift
index 34d4a0358d..3e8832e405 100644
--- a/library/swift/ResponseTrailersBuilder.swift
+++ b/library/swift/ResponseTrailersBuilder.swift
@@ -12,6 +12,6 @@ public final class ResponseTrailersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of response trailers.
   public func build() -> ResponseTrailers {
-    return ResponseTrailers(headers: self.headers)
+    return ResponseTrailers(headers: self.headers())
   }
 }
diff --git a/library/swift/grpc/GRPCRequestHeadersBuilder.swift b/library/swift/grpc/GRPCRequestHeadersBuilder.swift
index 177ddf9003..6f14926a86 100644
--- a/library/swift/grpc/GRPCRequestHeadersBuilder.swift
+++ b/library/swift/grpc/GRPCRequestHeadersBuilder.swift
@@ -40,6 +40,6 @@ public final class GRPCRequestHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of request headers.
   public func build() -> GRPCRequestHeaders {
-    return GRPCRequestHeaders(headers: self.headers)
+    return GRPCRequestHeaders(headers: self.headers())
   }
 }
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index 08c1540809..38871a1214 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -10,7 +10,7 @@ final class HeadersBuilderTests: XCTestCase {
     let headers = HeadersBuilder(headers: [:])
       .add(name: "x-foo", value: "1")
       .add(name: "x-foo", value: "2")
-      .headers
+      .headers()
     XCTAssertEqual(["1", "2"], headers["x-foo"])
   }
 
@@ -19,7 +19,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "x-foo", value: "1")
       .add(name: "x-foo", value: "2")
       .remove(name: "x-foo")
-      .headers
+      .headers()
     XCTAssertNil(headers["x-foo"])
   }
 
@@ -28,7 +28,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "x-foo", value: "123")
       .add(name: "x-bar", value: "abc")
       .remove(name: "x-foo")
-      .headers
+      .headers()
     XCTAssertEqual(["x-bar": ["abc"]], headers)
   }
 
@@ -36,34 +36,34 @@ final class HeadersBuilderTests: XCTestCase {
     let headers = HeadersBuilder(headers: [:])
       .add(name: "x-foo", value: "123")
       .set(name: "x-foo", value: ["abc"])
-      .headers
+      .headers()
     XCTAssertEqual(["x-foo": ["abc"]], headers)
   }
 
   func testInitializationIsCaseInsensitivePreservesCasingAndProcessesConflictingHeadersInAlphabeticalOrder() {
     let headers = HeadersBuilder(headers: ["a": ["456"], "A": ["123"]])
-    XCTAssertEqual(["A": ["123", "456"]], headers.headers)
+    XCTAssertEqual(["A": ["123", "456"]], headers.headers())
   }
 
   func testAddingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
     let headers = HeadersBuilder(headers: [:])
     headers.add(name: "fOo", value: "abc")
     headers.add(name: "foo", value: "123")
-    XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers)
+    XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers())
   }
 
   func testSettingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.set(name: "fOo", value: ["abc"])
-    XCTAssertEqual(["fOo": ["abc"]], headers.headers) 
+    XCTAssertEqual(["fOo": ["abc"]], headers.headers()) 
   }
 
   func testRemovingHeaderIsCaseInsensitive() {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.remove(name: "fOo")
-    XCTAssertEqual([:], headers.headers) 
+    XCTAssertEqual([:], headers.headers()) 
   }
 
   func testRestrictedHeadersAreNotSettable() {
@@ -71,7 +71,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "host", value: "example.com")
       .set(name: ":scheme", value: ["http"])
       .set(name: ":path", value: ["/nope"])
-      .headers
+      .headers()
     let expected = [
       ":authority": ["example.com"],
       ":path": ["/"],

From 3576622670d6873c00e6d55245388c412c0851e5 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 11:13:35 -0400
Subject: [PATCH 05/37] Fix formatting

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift   | 4 ++--
 test/swift/HeadersBuilderTests.swift | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 7c359d2c5d..6e21328234 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -38,7 +38,7 @@ public class HeadersBuilder: NSObject {
 
   func headers() -> [String: [String]] {
     return Dictionary(uniqueKeysWithValues: self._headers.map { _, value in
-        return (value.key, value.values) 
+        return (value.key, value.values)
     })
   }
 
@@ -122,7 +122,7 @@ public class HeadersBuilder: NSObject {
     for (name, values) in headers {
       let lowercasedName = name.lowercased()
       /// Dictionaries in Swift are unordered collections. We process headers with keys
-      /// that are the same when lowercased in an alphabetical order to avoid a situation 
+      /// that are the same when lowercased in an alphabetical order to avoid a situation
       /// in which the result of the initialization is underministic i.e., we want
       /// "[A: ["1"]", "a: ["2"]]" headers to be always converted to ["A": ["1", "2"]] and
       /// never to "a": ["2", "1"].
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index 38871a1214..dfc1cb807d 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -56,14 +56,14 @@ final class HeadersBuilderTests: XCTestCase {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.set(name: "fOo", value: ["abc"])
-    XCTAssertEqual(["fOo": ["abc"]], headers.headers()) 
+    XCTAssertEqual(["fOo": ["abc"]], headers.headers())
   }
 
   func testRemovingHeaderIsCaseInsensitive() {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.remove(name: "fOo")
-    XCTAssertEqual([:], headers.headers()) 
+    XCTAssertEqual([:], headers.headers())
   }
 
   func testRestrictedHeadersAreNotSettable() {

From f7538f2a07dcaa079f76ea8a3f6336dfee08dd4b Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 11:15:31 -0400
Subject: [PATCH 06/37] update version history

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 docs/root/intro/version_history.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/docs/root/intro/version_history.rst b/docs/root/intro/version_history.rst
index 70ad8b26f9..c3f8cd2eab 100644
--- a/docs/root/intro/version_history.rst
+++ b/docs/root/intro/version_history.rst
@@ -24,6 +24,7 @@ Bugfixes:
 - Android: update Kotlin standard libraries to 1.6.21 (:issue:`#2256 <2256>`)
 - fix bug where finalStreamIntel was not consistently set on cancel (:issue:`#2285 <2285>`)
 - iOS: fix termination crash in ProvisionalDispatcher (:issue:`#2059 <2059>`)
+- iOS: make headers lookup in HeadersBuilder case insensitive (:issue:`#2383 <2383>`)
 
 Features:
 

From 516a1fc66ef5ae924b2e4658ab38b9284d7c6331 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 11:21:02 -0400
Subject: [PATCH 07/37] Lint fixes

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift   | 4 ++--
 test/swift/HeadersBuilderTests.swift | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 6e21328234..4d496dfd9b 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -117,7 +117,6 @@ public class HeadersBuilder: NSObject {
   ///
   /// - parameter headers: The headers with which to start.
   required init(headers: [String: [String]]) {
-
     var processedHeaders = [String: KeyValuesPair]()
     for (name, values) in headers {
       let lowercasedName = name.lowercased()
@@ -131,7 +130,8 @@ public class HeadersBuilder: NSObject {
       /// if the currently processed header name is before the existing header name as
       /// determined by an alphabetical order.
       if let existing = processedHeaders[lowercasedName], existing.key > name {
-        processedHeaders[lowercasedName] = KeyValuesPair(key: name, values: values + existing.values)
+        processedHeaders[lowercasedName] =
+          KeyValuesPair(key: name, values: values + existing.values)
       } else {
         processedHeaders[lowercasedName, default: KeyValuesPair(key: name)].appendValues(values)
       }
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index dfc1cb807d..efa2b793c0 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -40,7 +40,7 @@ final class HeadersBuilderTests: XCTestCase {
     XCTAssertEqual(["x-foo": ["abc"]], headers)
   }
 
-  func testInitializationIsCaseInsensitivePreservesCasingAndProcessesConflictingHeadersInAlphabeticalOrder() {
+  func testInitializationIsCaseInsensitivePreservesCasingAndProcessesInAlphabeticalOrder() {
     let headers = HeadersBuilder(headers: ["a": ["456"], "A": ["123"]])
     XCTAssertEqual(["A": ["123", "456"]], headers.headers())
   }

From 42897f2e233d6e16e9a24bb2eaffdf2856925368 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 11:23:36 -0400
Subject: [PATCH 08/37] add doc

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift | 1 +
 1 file changed, 1 insertion(+)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 4d496dfd9b..8e62d3ea04 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -36,6 +36,7 @@ public class HeadersBuilder: NSObject {
 
   private var _headers: [String: KeyValuesPair]
 
+  /// Creates headers map.
   func headers() -> [String: [String]] {
     return Dictionary(uniqueKeysWithValues: self._headers.map { _, value in
         return (value.key, value.values)

From 0e328a09203cae6168a7afb583e8afcaaada820a Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 11:43:55 -0400
Subject: [PATCH 09/37] fix casing

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 8e62d3ea04..0c594a7188 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -7,8 +7,8 @@ private func isRestrictedHeader(name: String) -> Bool {
 }
 
 /// Base builder class used to construct `Headers` instances.
-/// It preserves the original casing of headers and enforces a case
-/// insensitive look up and setting of headers.
+/// It preserves the original casing of headers and enforces
+/// a case-insensitive look up and setting of headers.
 /// See `{Request|Response}HeadersBuilder` for usage.
 @objcMembers
 public class HeadersBuilder: NSObject {

From 8430f4f8250a94fb17fba70d35245047e129bffd Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 13:08:29 -0400
Subject: [PATCH 10/37] fix typo

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 docs/root/intro/version_history.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/root/intro/version_history.rst b/docs/root/intro/version_history.rst
index 2e59c4b29e..cf8232a2ca 100644
--- a/docs/root/intro/version_history.rst
+++ b/docs/root/intro/version_history.rst
@@ -24,7 +24,7 @@ Bugfixes:
 - Android: update Kotlin standard libraries to 1.6.21 (:issue:`#2256 <2256>`)
 - fix bug where finalStreamIntel was not consistently set on cancel (:issue:`#2285 <2285>`)
 - iOS: fix termination crash in ProvisionalDispatcher (:issue:`#2059 <2059>`)
-- iOS: make headers lookup in HeadersBuilder case insensitive (:issue:`#2383 <2383>`)
+- iOS: make headers lookup in HeadersBuilder case-insensitive (:issue:`#2383 <2383>`)
 - iOS: use correct DNS resolver when using C++ config builder (:issue: `#2378 <2378 >`)
 
 Features:

From 86ce3fc6d9fc3596089b33ac6b9277a6ce6f5482 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Thu, 23 Jun 2022 13:08:54 -0400
Subject: [PATCH 11/37] Improve version history

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 docs/root/intro/version_history.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/root/intro/version_history.rst b/docs/root/intro/version_history.rst
index cf8232a2ca..378cddf47f 100644
--- a/docs/root/intro/version_history.rst
+++ b/docs/root/intro/version_history.rst
@@ -24,7 +24,7 @@ Bugfixes:
 - Android: update Kotlin standard libraries to 1.6.21 (:issue:`#2256 <2256>`)
 - fix bug where finalStreamIntel was not consistently set on cancel (:issue:`#2285 <2285>`)
 - iOS: fix termination crash in ProvisionalDispatcher (:issue:`#2059 <2059>`)
-- iOS: make headers lookup in HeadersBuilder case-insensitive (:issue:`#2383 <2383>`)
+- iOS: make headers lookup in ``HeadersBuilder`` case-insensitive (:issue:`#2383 <2383>`)
 - iOS: use correct DNS resolver when using C++ config builder (:issue: `#2378 <2378 >`)
 
 Features:

From 37c6e5cbcd26b53891c8568ec0af8fc9256bdbfd Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Fri, 24 Jun 2022 18:09:21 -0400
Subject: [PATCH 12/37] Make Headers case-insensitive too

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 docs/root/intro/version_history.rst           |   2 +-
 library/swift/BUILD                           |   1 +
 library/swift/Headers.swift                   |  31 +++--
 library/swift/HeadersBuilder.swift            |  93 +++++----------
 library/swift/HeadersContainer.swift          | 111 ++++++++++++++++++
 library/swift/RequestHeaders.swift            |   2 +-
 library/swift/RequestHeadersBuilder.swift     |   2 +-
 library/swift/RequestTrailers.swift           |   2 +-
 library/swift/RequestTrailersBuilder.swift    |   4 +-
 library/swift/ResponseHeaders.swift           |   2 +-
 library/swift/ResponseHeadersBuilder.swift    |   4 +-
 library/swift/ResponseTrailers.swift          |   2 +-
 library/swift/ResponseTrailersBuilder.swift   |   4 +-
 library/swift/Stream.swift                    |   4 +-
 library/swift/filters/Filter.swift            |  28 ++---
 library/swift/grpc/GRPCRequestHeaders.swift   |   2 +-
 .../grpc/GRPCRequestHeadersBuilder.swift      |   2 +-
 library/swift/mocks/MockStream.swift          |   4 +-
 test/swift/BUILD                              |   1 +
 test/swift/HeadersBuilderTests.swift          |  18 +--
 test/swift/HeadersContainerTests.swift        |  75 ++++++++++++
 21 files changed, 278 insertions(+), 116 deletions(-)
 create mode 100644 library/swift/HeadersContainer.swift
 create mode 100644 test/swift/HeadersContainerTests.swift

diff --git a/docs/root/intro/version_history.rst b/docs/root/intro/version_history.rst
index 378cddf47f..2fdf016ac9 100644
--- a/docs/root/intro/version_history.rst
+++ b/docs/root/intro/version_history.rst
@@ -24,7 +24,7 @@ Bugfixes:
 - Android: update Kotlin standard libraries to 1.6.21 (:issue:`#2256 <2256>`)
 - fix bug where finalStreamIntel was not consistently set on cancel (:issue:`#2285 <2285>`)
 - iOS: fix termination crash in ProvisionalDispatcher (:issue:`#2059 <2059>`)
-- iOS: make headers lookup in ``HeadersBuilder`` case-insensitive (:issue:`#2383 <2383>`)
+- iOS: make headers lookup in ``HeadersBuilder`` and ``Headers`` case-insensitive (:issue:`#2383 <2383>`)
 - iOS: use correct DNS resolver when using C++ config builder (:issue: `#2378 <2378 >`)
 
 Features:
diff --git a/library/swift/BUILD b/library/swift/BUILD
index 3fcdd55f08..6bbc9cb69d 100644
--- a/library/swift/BUILD
+++ b/library/swift/BUILD
@@ -17,6 +17,7 @@ swift_library(
         "FinalStreamIntel.swift",
         "Headers.swift",
         "HeadersBuilder.swift",
+        "HeadersContainer.swift",
         "KeyValueStore.swift",
         "LogLevel.swift",
         "NetworkMonitoringMode.swift",
diff --git a/library/swift/Headers.swift b/library/swift/Headers.swift
index 094a039294..0c93008411 100644
--- a/library/swift/Headers.swift
+++ b/library/swift/Headers.swift
@@ -4,38 +4,51 @@ import Foundation
 /// To instantiate new instances, see `{Request|Response}HeadersBuilder`.
 @objcMembers
 public class Headers: NSObject {
-  let headers: [String: [String]]
+  let container: HeadersContainer
 
   /// Get the value for the provided header name.
   ///
-  /// - parameter name: Header name for which to get the current value.
+  /// - parameter name: The case-insensitive header name for which to
+  ///                   get the current value.
+  ///                   
   ///
   /// - returns: The current headers specified for the provided name.
   public func value(forName name: String) -> [String]? {
-    return self.headers[name]
+    return self.container.value(forName: name)
   }
 
   /// Accessor for all underlying headers as a map.
   ///
   /// - returns: The underlying headers.
   public func allHeaders() -> [String: [String]] {
-    return self.headers
+    return self.container.allHeaders()
   }
 
   /// Internal initializer used by builders.
   ///
-  /// - parameter headers: Headers to set.
-  required init(headers: [String: [String]]) {
-    self.headers = headers
+  /// - parameter container: Headers to set.
+  required init(container: HeadersContainer) {
+    self.container = container
     super.init()
   }
+
+  /// Inialize the receiver with a given headers map.
+  ///
+  /// - parameter headers: The headers map to use.
+  convenience init(headers: [String: [String]]) {
+    self.init(container: HeadersContainer(headers: headers))
+  }
+
+  override convenience init() {
+    self.init(headers: [:])
+  }
 }
 
 // MARK: - Equatable
 
 extension Headers {
   public override func isEqual(_ object: Any?) -> Bool {
-    return (object as? Self)?.headers == self.headers
+    return (object as? Self)?.container == self.container
   }
 }
 
@@ -43,6 +56,6 @@ extension Headers {
 
 extension Headers {
   public override var description: String {
-    return "\(type(of: self)) \(self.headers.description)"
+    return "\(type(of: self)) \(self.container.description)"
   }
 }
diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 0c594a7188..d0cde1a1d7 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,7 +3,8 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  return name == "host" || kRestrictedPrefixes.contains { name.hasPrefix($0) }
+  let lowercasedName = name.lowercased()
+  return lowercasedName == "host" || kRestrictedPrefixes.contains { lowercasedName.hasPrefix($0) }
 }
 
 /// Base builder class used to construct `Headers` instances.
@@ -12,36 +13,7 @@ private func isRestrictedHeader(name: String) -> Bool {
 /// See `{Request|Response}HeadersBuilder` for usage.
 @objcMembers
 public class HeadersBuilder: NSObject {
-  struct KeyValuesPair {
-    private(set) var key: String
-    private(set) var values: [String]
-
-    init(key: String, values: [String] = []) {
-      self.key = key
-      self.values = values
-    }
-
-    mutating func appendValue(_ value: String) {
-      self.values.append(value)
-    }
-
-    mutating func appendValues(_ values: [String]) {
-      self.values.append(contentsOf: values)
-    }
-
-    mutating func setValue(_ value: String) {
-      self.values = [value]
-    }
-  }
-
-  private var _headers: [String: KeyValuesPair]
-
-  /// Creates headers map.
-  func headers() -> [String: [String]] {
-    return Dictionary(uniqueKeysWithValues: self._headers.map { _, value in
-        return (value.key, value.values)
-    })
-  }
+  private(set) var container: HeadersContainer
 
   /// Append a value to the header name.
   ///
@@ -51,12 +23,11 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func add(name: String, value: String) -> Self {
-    let lowercasedName = name.lowercased()
-    if isRestrictedHeader(name: lowercasedName) {
+    if isRestrictedHeader(name: name) {
       return self
     }
 
-    self._headers[lowercasedName, default: KeyValuesPair(key: name)].appendValue(value)
+    self.container.add(name: name, value: value)
     return self
   }
 
@@ -68,12 +39,11 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func set(name: String, value: [String]) -> Self {
-    let lowercasedName = name.lowercased()
-    if isRestrictedHeader(name: lowercasedName) {
+    if isRestrictedHeader(name: name) {
       return self
     }
 
-    self._headers[lowercasedName] = KeyValuesPair(key: name, values: value)
+    self.container.set(name: name, value: value)
     return self
   }
 
@@ -84,12 +54,11 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   public func remove(name: String) -> Self {
-    let lowercasedName = name.lowercased()
-    if isRestrictedHeader(name: lowercasedName) {
+    if isRestrictedHeader(name: name) {
       return self
     }
 
-    self._headers[lowercasedName] = nil
+    self.container.set(name: name, value: nil)
     return self
   }
 
@@ -103,42 +72,34 @@ public class HeadersBuilder: NSObject {
   /// - returns: This builder.
   @discardableResult
   func internalSet(name: String, value: [String]) -> Self {
-    self._headers[name.lowercased()] = KeyValuesPair(key: name, values: value)
+    self.container.set(name: name, value: value)
     return self
   }
 
+  func allHeaders() -> [String: [String]] {
+    return self.container.allHeaders()
+  }
+
   // Only explicitly implemented to work around a swiftinterface issue in Swift 5.1. This can be
   // removed once envoy is only built with Swift 5.2+
   public override init() {
-    self._headers = [:]
+    self.container = HeadersContainer()
     super.init()
   }
 
-  /// Initialize a new builder. Subclasses should provide their own public convenience initializers.
+  // Initialize a new builder using the provided headers container.
   ///
-  /// - parameter headers: The headers with which to start.
-  required init(headers: [String: [String]]) {
-    var processedHeaders = [String: KeyValuesPair]()
-    for (name, values) in headers {
-      let lowercasedName = name.lowercased()
-      /// Dictionaries in Swift are unordered collections. We process headers with keys
-      /// that are the same when lowercased in an alphabetical order to avoid a situation
-      /// in which the result of the initialization is underministic i.e., we want
-      /// "[A: ["1"]", "a: ["2"]]" headers to be always converted to ["A": ["1", "2"]] and
-      /// never to "a": ["2", "1"].
-      ///
-      /// If a given header name already exists in the processed headers map, check
-      /// if the currently processed header name is before the existing header name as
-      /// determined by an alphabetical order.
-      if let existing = processedHeaders[lowercasedName], existing.key > name {
-        processedHeaders[lowercasedName] =
-          KeyValuesPair(key: name, values: values + existing.values)
-      } else {
-        processedHeaders[lowercasedName, default: KeyValuesPair(key: name)].appendValues(values)
-      }
-    }
+  /// - parameter: The headers container to initialize the receiver with.
+  init(container: HeadersContainer) {
+    self.container = container
+    super.init()
+  }
 
-    self._headers = processedHeaders
+  // Initialize a new builder. Subclasses should provide their own public convenience initializers.
+  //
+  // - parameter headers: The headers with which to start.
+  init(headers: [String: [String]]) {
+    self.container = HeadersContainer(headers: headers)
     super.init()
   }
 }
@@ -147,6 +108,6 @@ public class HeadersBuilder: NSObject {
 
 extension HeadersBuilder {
   public override func isEqual(_ object: Any?) -> Bool {
-    return (object as? Self)?.headers() == self.headers()
+    return (object as? Self)?.container == self.container
   }
 }
diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
new file mode 100644
index 0000000000..d7df6464dc
--- /dev/null
+++ b/library/swift/HeadersContainer.swift
@@ -0,0 +1,111 @@
+/// The container which manages the underlying headers map.
+/// It maintains the original casing of passed header names.
+/// It treats headers names as case-insensitive for the purpose
+/// of headers lookup and header name conflict resolutions.
+struct HeadersContainer: Equatable {
+  private var headers: [String: Header]
+
+  // Represents a headers name together with all of its values.
+  // It preserves the original casing of the header name.
+  struct Header: Equatable {
+    private(set) var name: String
+    private(set) var value: [String]
+
+    init(name: String, value: [String] = []) {
+      self.name = name
+      self.value = value
+    }
+
+    mutating func addValue(_ value: [String]) {
+      self.value.append(contentsOf: value)
+    }
+
+     mutating func addValue(_ value: String) {
+      self.value.append(value)
+    }
+  }
+
+  /// Initialize a new instance of the receiver using the provided headers map.
+  ///
+  /// - parameter headers: The headers map.
+  init(headers: [String: [String]]) {
+    var underlyingHeaders = [String: Header]()
+    for (name, value) in headers {
+      let lowercasedName = name.lowercased()
+      /// Dictionaries in Swift are unordered collections. Process headers with names
+      /// that are the same when lowercased in an alphabetical order to avoid a situation
+      /// in which the result of the initialization is underministic i.e., we want
+      /// "[A: ["1"]", "a: ["2"]]" headers to be always converted to ["A": ["1", "2"]] and
+      /// never to "a": ["2", "1"].
+      ///
+      /// If a given header name already exists in the processed headers map, check
+      /// if the currently processed header name is before the existing header name as
+      /// determined by an alphabetical order.
+      if let existing = underlyingHeaders[lowercasedName], existing.name > name {
+        underlyingHeaders[lowercasedName] =
+          Header(name: name, value: value + existing.value)
+      } else {
+        let `default` = Header(name: underlyingHeaders[lowercasedName]?.name ?? name)
+        underlyingHeaders[lowercasedName, default: `default`].addValue(value)
+      }
+    }
+    self.headers = underlyingHeaders
+  }
+
+  /// Initialize an empty headers container.
+  init() {
+    self.headers = [:]
+  }
+
+  /// Add a value to a header with a given name.
+  ///
+  /// - parameter name:  The name of the header. For the purpose of headers lookup
+  ///                    and header name conflict resolution, the name of the header
+  ///                    is considered to be case-insensitive.
+  /// - parameter value: The value to add.
+  mutating func add(name: String, value: String) {
+      self.headers[name.lowercased(), default: Header(name: name)].addValue(value)
+  }
+
+  /// Add values to a header with a given name.
+  ///
+  /// - parameter name:   The name of the header.
+  /// - parameter values: The values to add.
+  mutating func add(name: String, value: [String]) {
+    self.headers[name.lowercased(), default: Header(name: name)].addValue(value)
+  }
+
+  /// Set the value of a given header.
+  ///
+  /// - parameter name:  The name of the header.
+  /// - parameter value: The value to set the header value to.
+  mutating func set(name: String, value: [String]?) {
+    guard let value = value else {
+      self.headers[name.lowercased()] = nil
+      return
+    }
+    self.headers[name.lowercased()] = Header(name: name, value: value)
+  }
+
+  /// Returns the value of a given header.
+  ///
+  /// - parameter name: The name of the header to return the value for.
+  ///
+  /// - returns: The value associated with a given header.
+  func value(forName name: String) -> [String]? {
+    return self.headers[name.lowercased()]?.value
+  }
+
+  /// The list of all headers stored by the receiver.
+  func allHeaders() -> [String: [String]] {
+      Dictionary(uniqueKeysWithValues: self.headers.map { _, value in
+        return (value.name, value.value)
+    })
+  }
+}
+
+extension HeadersContainer: CustomStringConvertible {
+  var description: String {
+    return self.headers.description
+  }
+}
diff --git a/library/swift/RequestHeaders.swift b/library/swift/RequestHeaders.swift
index e9e8e10ff1..8da6194e10 100644
--- a/library/swift/RequestHeaders.swift
+++ b/library/swift/RequestHeaders.swift
@@ -29,6 +29,6 @@ public class RequestHeaders: Headers {
   ///
   /// - returns: The new builder.
   public func toRequestHeadersBuilder() -> RequestHeadersBuilder {
-    return RequestHeadersBuilder(headers: self.headers)
+    return RequestHeadersBuilder(container: self.container)
   }
 }
diff --git a/library/swift/RequestHeadersBuilder.swift b/library/swift/RequestHeadersBuilder.swift
index 8b4d64cde7..54b8652adf 100644
--- a/library/swift/RequestHeadersBuilder.swift
+++ b/library/swift/RequestHeadersBuilder.swift
@@ -52,6 +52,6 @@ public final class RequestHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of request headers.
   public func build() -> RequestHeaders {
-    return RequestHeaders(headers: self.headers())
+    return RequestHeaders(container: self.container)
   }
 }
diff --git a/library/swift/RequestTrailers.swift b/library/swift/RequestTrailers.swift
index a525c6acc6..0df0760f82 100644
--- a/library/swift/RequestTrailers.swift
+++ b/library/swift/RequestTrailers.swift
@@ -7,6 +7,6 @@ public final class RequestTrailers: Trailers {
   ///
   /// - returns: The new builder.
   public func toRequestTrailersBuilder() -> RequestTrailersBuilder {
-    return RequestTrailersBuilder(headers: self.headers)
+    return RequestTrailersBuilder(container: self.container)
   }
 }
diff --git a/library/swift/RequestTrailersBuilder.swift b/library/swift/RequestTrailersBuilder.swift
index a521549f2c..e146a21372 100644
--- a/library/swift/RequestTrailersBuilder.swift
+++ b/library/swift/RequestTrailersBuilder.swift
@@ -5,13 +5,13 @@ import Foundation
 public final class RequestTrailersBuilder: HeadersBuilder {
   /// Initialize a new instance of the builder.
   public override convenience init() {
-    self.init(headers: [:])
+    self.init(container: HeadersContainer(headers: [:]))
   }
 
   /// Build the request trailers using the current builder.
   ///
   /// - returns: New instance of request trailers.
   public func build() -> RequestTrailers {
-    return RequestTrailers(headers: self.headers())
+    return RequestTrailers(container: self.container)
   }
 }
diff --git a/library/swift/ResponseHeaders.swift b/library/swift/ResponseHeaders.swift
index a2ca41a133..ce24f6a880 100644
--- a/library/swift/ResponseHeaders.swift
+++ b/library/swift/ResponseHeaders.swift
@@ -11,6 +11,6 @@ public final class ResponseHeaders: Headers {
   ///
   /// - returns: The new builder.
   public func toResponseHeadersBuilder() -> ResponseHeadersBuilder {
-    return ResponseHeadersBuilder(headers: self.headers)
+    return ResponseHeadersBuilder(container: self.container)
   }
 }
diff --git a/library/swift/ResponseHeadersBuilder.swift b/library/swift/ResponseHeadersBuilder.swift
index 970a75ec93..fc62d605a2 100644
--- a/library/swift/ResponseHeadersBuilder.swift
+++ b/library/swift/ResponseHeadersBuilder.swift
@@ -5,7 +5,7 @@ import Foundation
 public final class ResponseHeadersBuilder: HeadersBuilder {
   /// Initialize a new instance of the builder.
   public override convenience init() {
-    self.init(headers: [:])
+    self.init(container: HeadersContainer(headers: [:]))
   }
 
   /// Add an HTTP status to the response headers.
@@ -23,6 +23,6 @@ public final class ResponseHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of response headers.
   public func build() -> ResponseHeaders {
-    return ResponseHeaders(headers: self.headers())
+    return ResponseHeaders(container: self.container)
   }
 }
diff --git a/library/swift/ResponseTrailers.swift b/library/swift/ResponseTrailers.swift
index 2b25a8b45e..c3e0571904 100644
--- a/library/swift/ResponseTrailers.swift
+++ b/library/swift/ResponseTrailers.swift
@@ -7,6 +7,6 @@ public final class ResponseTrailers: Trailers {
   ///
   /// - returns: The new builder.
   public func toResponseTrailersBuilder() -> ResponseTrailersBuilder {
-    return ResponseTrailersBuilder(headers: self.headers)
+    return ResponseTrailersBuilder(container: self.container)
   }
 }
diff --git a/library/swift/ResponseTrailersBuilder.swift b/library/swift/ResponseTrailersBuilder.swift
index 3e8832e405..6d02fbbf0e 100644
--- a/library/swift/ResponseTrailersBuilder.swift
+++ b/library/swift/ResponseTrailersBuilder.swift
@@ -5,13 +5,13 @@ import Foundation
 public final class ResponseTrailersBuilder: HeadersBuilder {
   /// Initialize a new instance of the builder.
   public override convenience init() {
-    self.init(headers: [:])
+    self.init(container: HeadersContainer())
   }
 
   /// Build the response trailers using the current builder.
   ///
   /// - returns: New instance of response trailers.
   public func build() -> ResponseTrailers {
-    return ResponseTrailers(headers: self.headers())
+    return ResponseTrailers(container: self.container)
   }
 }
diff --git a/library/swift/Stream.swift b/library/swift/Stream.swift
index a9b416e6f9..0a0e8ddc0a 100644
--- a/library/swift/Stream.swift
+++ b/library/swift/Stream.swift
@@ -26,7 +26,7 @@ public class Stream: NSObject {
   /// - returns: This stream, for chaining syntax.
   @discardableResult
   public func sendHeaders(_ headers: RequestHeaders, endStream: Bool) -> Stream {
-    self.underlyingStream.sendHeaders(headers.headers, close: endStream)
+    self.underlyingStream.sendHeaders(headers.allHeaders(), close: endStream)
     return self
   }
 
@@ -57,7 +57,7 @@ public class Stream: NSObject {
   ///
   /// - parameter trailers: Trailers with which to close the stream.
   public func close(trailers: RequestTrailers) {
-    self.underlyingStream.sendTrailers(trailers.headers)
+    self.underlyingStream.sendTrailers(trailers.allHeaders())
   }
 
   /// Close the stream with a data frame.
diff --git a/library/swift/filters/Filter.swift b/library/swift/filters/Filter.swift
index ebd87a5024..8835fbc078 100644
--- a/library/swift/filters/Filter.swift
+++ b/library/swift/filters/Filter.swift
@@ -27,7 +27,7 @@ extension EnvoyHTTPFilter {
                                                     streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let headers):
-          return [kEnvoyFilterHeadersStatusContinue, headers.headers]
+          return [kEnvoyFilterHeadersStatusContinue, headers.allHeaders()]
         case .stopIteration:
           return [kEnvoyFilterHeadersStatusStopIteration, NSNull()]
         }
@@ -44,7 +44,7 @@ extension EnvoyHTTPFilter {
         case .stopIterationNoBuffer:
           return [kEnvoyFilterDataStatusStopIterationNoBuffer, NSNull()]
         case .resumeIteration(let headers, let data):
-          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.headers as Any]
+          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.allHeaders() as Any]
         }
       }
 
@@ -53,14 +53,14 @@ extension EnvoyHTTPFilter {
                                                      streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let trailers):
-          return [kEnvoyFilterTrailersStatusContinue, trailers.headers]
+          return [kEnvoyFilterTrailersStatusContinue, trailers.allHeaders()]
         case .stopIteration:
           return [kEnvoyFilterTrailersStatusStopIteration, NSNull()]
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterTrailersStatusResumeIteration,
-            trailers.headers,
-            headers?.headers as Any,
+            trailers.allHeaders(),
+            headers?.allHeaders() as Any,
             data as Any,
           ]
         }
@@ -74,7 +74,7 @@ extension EnvoyHTTPFilter {
                                                       streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let headers):
-          return [kEnvoyFilterHeadersStatusContinue, headers.headers]
+          return [kEnvoyFilterHeadersStatusContinue, headers.allHeaders()]
         case .stopIteration:
           return [kEnvoyFilterHeadersStatusStopIteration, NSNull()]
         }
@@ -91,7 +91,7 @@ extension EnvoyHTTPFilter {
         case .stopIterationNoBuffer:
           return [kEnvoyFilterDataStatusStopIterationNoBuffer, NSNull()]
         case .resumeIteration(let headers, let data):
-          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.headers as Any]
+          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.allHeaders() as Any]
         }
       }
 
@@ -100,14 +100,14 @@ extension EnvoyHTTPFilter {
                                                        streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let trailers):
-          return [kEnvoyFilterTrailersStatusContinue, trailers.headers]
+          return [kEnvoyFilterTrailersStatusContinue, trailers.allHeaders()]
         case .stopIteration:
           return [kEnvoyFilterTrailersStatusStopIteration, NSNull()]
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterTrailersStatusResumeIteration,
-            trailers.headers,
-            headers?.headers as Any,
+            trailers.allHeaders(),
+            headers?.allHeaders() as Any,
             data as Any,
           ]
         }
@@ -146,9 +146,9 @@ extension EnvoyHTTPFilter {
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterResumeStatusResumeIteration,
-            headers?.headers as Any,
+            headers?.allHeaders() as Any,
             data as Any,
-            trailers?.headers as Any,
+            trailers?.allHeaders() as Any,
           ]
         }
       }
@@ -172,9 +172,9 @@ extension EnvoyHTTPFilter {
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterResumeStatusResumeIteration,
-            headers?.headers as Any,
+            headers?.allHeaders() as Any,
             data as Any,
-            trailers?.headers as Any,
+            trailers?.allHeaders() as Any,
           ]
         }
       }
diff --git a/library/swift/grpc/GRPCRequestHeaders.swift b/library/swift/grpc/GRPCRequestHeaders.swift
index a5c589b5f8..cdf55cca19 100644
--- a/library/swift/grpc/GRPCRequestHeaders.swift
+++ b/library/swift/grpc/GRPCRequestHeaders.swift
@@ -7,6 +7,6 @@ public final class GRPCRequestHeaders: RequestHeaders {
   ///
   /// - returns: The new builder.
   public func toGRPCRequestHeadersBuilder() -> GRPCRequestHeadersBuilder {
-    return GRPCRequestHeadersBuilder(headers: self.headers)
+    return GRPCRequestHeadersBuilder(container: self.container)
   }
 }
diff --git a/library/swift/grpc/GRPCRequestHeadersBuilder.swift b/library/swift/grpc/GRPCRequestHeadersBuilder.swift
index 6f14926a86..0f3fc8ba1b 100644
--- a/library/swift/grpc/GRPCRequestHeadersBuilder.swift
+++ b/library/swift/grpc/GRPCRequestHeadersBuilder.swift
@@ -40,6 +40,6 @@ public final class GRPCRequestHeadersBuilder: HeadersBuilder {
   ///
   /// - returns: New instance of request headers.
   public func build() -> GRPCRequestHeaders {
-    return GRPCRequestHeaders(headers: self.headers())
+    return GRPCRequestHeaders(container: self.container)
   }
 }
diff --git a/library/swift/mocks/MockStream.swift b/library/swift/mocks/MockStream.swift
index 8aa331f03c..d383d62d78 100644
--- a/library/swift/mocks/MockStream.swift
+++ b/library/swift/mocks/MockStream.swift
@@ -52,7 +52,7 @@ public final class MockStream: Stream {
   /// - parameter headers:   Response headers to receive.
   /// - parameter endStream: Whether this is a headers-only response.
   public func receiveHeaders(_ headers: ResponseHeaders, endStream: Bool) {
-    self.mockStream.callbacks.onHeaders(headers.headers, endStream, EnvoyStreamIntel())
+    self.mockStream.callbacks.onHeaders(headers.allHeaders(), endStream, EnvoyStreamIntel())
   }
 
   /// Simulate response data coming back over the stream.
@@ -67,7 +67,7 @@ public final class MockStream: Stream {
   ///
   /// - parameter trailers: Response trailers to receive.
   public func receiveTrailers(_ trailers: ResponseTrailers) {
-    self.mockStream.callbacks.onTrailers(trailers.headers, EnvoyStreamIntel())
+    self.mockStream.callbacks.onTrailers(trailers.allHeaders(), EnvoyStreamIntel())
   }
 
   /// Simulate the stream receiving a cancellation signal from Envoy.
diff --git a/test/swift/BUILD b/test/swift/BUILD
index 5f98ee480e..1839c45e50 100644
--- a/test/swift/BUILD
+++ b/test/swift/BUILD
@@ -9,6 +9,7 @@ envoy_mobile_swift_test(
         "GRPCRequestHeadersBuilderTests.swift",
         "GRPCStreamTests.swift",
         "HeadersBuilderTests.swift",
+        "HeadersContainerTests.swift",
         "PulseClientImplTests.swift",
         "RequestHeadersBuilderTests.swift",
         "ResponseHeadersTests.swift",
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index efa2b793c0..4d08c0c4af 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -10,7 +10,7 @@ final class HeadersBuilderTests: XCTestCase {
     let headers = HeadersBuilder(headers: [:])
       .add(name: "x-foo", value: "1")
       .add(name: "x-foo", value: "2")
-      .headers()
+      .allHeaders()
     XCTAssertEqual(["1", "2"], headers["x-foo"])
   }
 
@@ -19,7 +19,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "x-foo", value: "1")
       .add(name: "x-foo", value: "2")
       .remove(name: "x-foo")
-      .headers()
+      .allHeaders()
     XCTAssertNil(headers["x-foo"])
   }
 
@@ -28,7 +28,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "x-foo", value: "123")
       .add(name: "x-bar", value: "abc")
       .remove(name: "x-foo")
-      .headers()
+      .allHeaders()
     XCTAssertEqual(["x-bar": ["abc"]], headers)
   }
 
@@ -36,34 +36,34 @@ final class HeadersBuilderTests: XCTestCase {
     let headers = HeadersBuilder(headers: [:])
       .add(name: "x-foo", value: "123")
       .set(name: "x-foo", value: ["abc"])
-      .headers()
+      .allHeaders()
     XCTAssertEqual(["x-foo": ["abc"]], headers)
   }
 
   func testInitializationIsCaseInsensitivePreservesCasingAndProcessesInAlphabeticalOrder() {
     let headers = HeadersBuilder(headers: ["a": ["456"], "A": ["123"]])
-    XCTAssertEqual(["A": ["123", "456"]], headers.headers())
+    XCTAssertEqual(["A": ["123", "456"]], headers.allHeaders())
   }
 
   func testAddingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
     let headers = HeadersBuilder(headers: [:])
     headers.add(name: "fOo", value: "abc")
     headers.add(name: "foo", value: "123")
-    XCTAssertEqual(["fOo": ["abc", "123"]], headers.headers())
+    XCTAssertEqual(["fOo": ["abc", "123"]], headers.allHeaders())
   }
 
   func testSettingHeaderIsCaseInsensitiveAndHeaderCasingIsPreserved() {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.set(name: "fOo", value: ["abc"])
-    XCTAssertEqual(["fOo": ["abc"]], headers.headers())
+    XCTAssertEqual(["fOo": ["abc"]], headers.allHeaders())
   }
 
   func testRemovingHeaderIsCaseInsensitive() {
     let headers = HeadersBuilder(headers: [:])
     headers.set(name: "foo", value: ["123"])
     headers.remove(name: "fOo")
-    XCTAssertEqual([:], headers.headers())
+    XCTAssertEqual([:], headers.allHeaders())
   }
 
   func testRestrictedHeadersAreNotSettable() {
@@ -71,7 +71,7 @@ final class HeadersBuilderTests: XCTestCase {
       .add(name: "host", value: "example.com")
       .set(name: ":scheme", value: ["http"])
       .set(name: ":path", value: ["/nope"])
-      .headers()
+      .allHeaders()
     let expected = [
       ":authority": ["example.com"],
       ":path": ["/"],
diff --git a/test/swift/HeadersContainerTests.swift b/test/swift/HeadersContainerTests.swift
new file mode 100644
index 0000000000..1d918a5130
--- /dev/null
+++ b/test/swift/HeadersContainerTests.swift
@@ -0,0 +1,75 @@
+@testable import Envoy
+import XCTest
+
+final class HeadersContainerTests: XCTestCase {
+  func testInitializationPreservesAllHeadersFromInputHeadersMap() {
+    let container = HeadersContainer(headers: ["a": ["456"], "b": ["123"]])
+    XCTAssertEqual(["a": ["456"], "b": ["123"]], container.allHeaders())
+  }
+
+  func testInitializationIsCaseInsensitivePreservesCasingAndProcessesInAlphabeticalOrder() {
+    let container = HeadersContainer(headers: ["a": ["456"], "A": ["123"]])
+    XCTAssertEqual(["A": ["123", "456"]], container.allHeaders())
+  }
+
+  func testAddingHeaderValueAddsToListOfHeader() {
+    var container =  HeadersContainer()
+    container.add(name: "x-foo", value: "1")
+    container.add(name: "x-foo", value: "2")
+
+    XCTAssertEqual(["1", "2"], container.value(forName: "x-foo"))
+  }
+
+  func testAddingHeaderValueIsCaseInsensitiveAndPreservesHeaderNameCasing() {
+    var container =  HeadersContainer()
+    container.add(name: "x-FOO", value: "1")
+    container.add(name: "x-foo", value: "2")
+
+    XCTAssertEqual(["1", "2"], container.value(forName: "x-foo"))
+    XCTAssertEqual(["x-FOO": ["1", "2"]], container.allHeaders())
+  }
+
+  func testAddingHeadersValuesAddsToListOfHeaders() {
+    var container =  HeadersContainer()
+    container.add(name: "x-foo", value: ["1", "2"])
+    container.add(name: "x-foo", value: ["3", "4"])
+
+    XCTAssertEqual(["1", "2", "3", "4"], container.value(forName: "x-foo"))
+  }
+
+  func testAddingHeaderValuesIsCaseInsensitiveAndPreservesHeaderNameCasing() {
+    var container =  HeadersContainer()
+    container.add(name: "x-FOO", value: ["1", "2"])
+    container.add(name: "x-foo", value: ["3", "4"])
+
+    XCTAssertEqual(["1", "2", "3", "4"], container.value(forName: "x-foo"))
+    XCTAssertEqual(["x-FOO": ["1", "2", "3", "4"]], container.allHeaders())
+  }
+
+  func testSettingHeaderToNilRemovesAllOfItsValues() {
+    var container = HeadersContainer()
+    container.add(name: "x-foo", value: "1")
+    container.add(name: "x-foo", value: "2")
+    container.set(name: "x-foo", value: nil)
+
+    XCTAssertNil(container.value(forName: "x-foo"))
+  }
+
+  func testSettingHeaderToNilPerformsCaseInsensitiveHeaderNameLookup() {
+    var container =  HeadersContainer()
+    container.add(name: "x-FOO", value: "1")
+    container.add(name: "x-foo", value: "2")
+    container.set(name: "x-foo", value: nil)
+
+    XCTAssertNil(container.value(forName: "x-foo"))
+  }
+
+  func testLookupIsCaseInsensitive() {
+    var container =  HeadersContainer()
+    container.add(name: "x-FOO", value: "1")
+
+    XCTAssertEqual(["1"], container.value(forName: "x-foo"))
+    XCTAssertEqual(["1"], container.value(forName: "x-fOo"))
+    XCTAssertEqual(["1"], container.value(forName: "x-FOO"))
+  }
+}
\ No newline at end of file

From 35c0536dc719650335917f39e24ec7ada69b0934 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Fri, 24 Jun 2022 18:11:22 -0400
Subject: [PATCH 13/37] lint fixes

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/Headers.swift            | 2 +-
 test/swift/HeadersContainerTests.swift | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/swift/Headers.swift b/library/swift/Headers.swift
index 0c93008411..9aff6e5b79 100644
--- a/library/swift/Headers.swift
+++ b/library/swift/Headers.swift
@@ -10,7 +10,7 @@ public class Headers: NSObject {
   ///
   /// - parameter name: The case-insensitive header name for which to
   ///                   get the current value.
-  ///                   
+  ///
   ///
   /// - returns: The current headers specified for the provided name.
   public func value(forName name: String) -> [String]? {
diff --git a/test/swift/HeadersContainerTests.swift b/test/swift/HeadersContainerTests.swift
index 1d918a5130..a915e98b79 100644
--- a/test/swift/HeadersContainerTests.swift
+++ b/test/swift/HeadersContainerTests.swift
@@ -72,4 +72,4 @@ final class HeadersContainerTests: XCTestCase {
     XCTAssertEqual(["1"], container.value(forName: "x-fOo"))
     XCTAssertEqual(["1"], container.value(forName: "x-FOO"))
   }
-}
\ No newline at end of file
+}

From 1fd993826a88b79032ce83b0a5b5bf996a0e2e16 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Fri, 24 Jun 2022 18:12:42 -0400
Subject: [PATCH 14/37] swiftlint fix

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersContainer.swift   |  4 ++--
 test/swift/HeadersContainerTests.swift | 12 ++++++------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index d7df6464dc..d89f6125e8 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -98,8 +98,8 @@ struct HeadersContainer: Equatable {
 
   /// The list of all headers stored by the receiver.
   func allHeaders() -> [String: [String]] {
-      Dictionary(uniqueKeysWithValues: self.headers.map { _, value in
-        return (value.name, value.value)
+    return Dictionary(uniqueKeysWithValues: self.headers.map { _, value in
+      return (value.name, value.value)
     })
   }
 }
diff --git a/test/swift/HeadersContainerTests.swift b/test/swift/HeadersContainerTests.swift
index a915e98b79..394fc38421 100644
--- a/test/swift/HeadersContainerTests.swift
+++ b/test/swift/HeadersContainerTests.swift
@@ -13,7 +13,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testAddingHeaderValueAddsToListOfHeader() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-foo", value: "1")
     container.add(name: "x-foo", value: "2")
 
@@ -21,7 +21,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testAddingHeaderValueIsCaseInsensitiveAndPreservesHeaderNameCasing() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-FOO", value: "1")
     container.add(name: "x-foo", value: "2")
 
@@ -30,7 +30,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testAddingHeadersValuesAddsToListOfHeaders() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-foo", value: ["1", "2"])
     container.add(name: "x-foo", value: ["3", "4"])
 
@@ -38,7 +38,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testAddingHeaderValuesIsCaseInsensitiveAndPreservesHeaderNameCasing() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-FOO", value: ["1", "2"])
     container.add(name: "x-foo", value: ["3", "4"])
 
@@ -56,7 +56,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testSettingHeaderToNilPerformsCaseInsensitiveHeaderNameLookup() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-FOO", value: "1")
     container.add(name: "x-foo", value: "2")
     container.set(name: "x-foo", value: nil)
@@ -65,7 +65,7 @@ final class HeadersContainerTests: XCTestCase {
   }
 
   func testLookupIsCaseInsensitive() {
-    var container =  HeadersContainer()
+    var container = HeadersContainer()
     container.add(name: "x-FOO", value: "1")
 
     XCTAssertEqual(["1"], container.value(forName: "x-foo"))

From 6389322f5fb40484a56ea7ea4891e042900f7aa7 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Fri, 24 Jun 2022 21:51:56 -0400
Subject: [PATCH 15/37] doc string fix

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersContainer.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index d89f6125e8..9c26efcbba 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -70,7 +70,7 @@ struct HeadersContainer: Equatable {
   /// Add values to a header with a given name.
   ///
   /// - parameter name:   The name of the header.
-  /// - parameter values: The values to add.
+  /// - parameter value: The values to add.
   mutating func add(name: String, value: [String]) {
     self.headers[name.lowercased(), default: Header(name: name)].addValue(value)
   }

From 3ac922cf0791f80f1429407eb67e172a8287e71b Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Sat, 25 Jun 2022 00:10:03 -0400
Subject: [PATCH 16/37] remove method

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersContainer.swift   | 10 +---------
 test/swift/HeadersContainerTests.swift | 19 +++++++++----------
 2 files changed, 10 insertions(+), 19 deletions(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index 9c26efcbba..5a16fcdb3c 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -20,7 +20,7 @@ struct HeadersContainer: Equatable {
       self.value.append(contentsOf: value)
     }
 
-     mutating func addValue(_ value: String) {
+    mutating func addValue(_ value: String) {
       self.value.append(value)
     }
   }
@@ -67,14 +67,6 @@ struct HeadersContainer: Equatable {
       self.headers[name.lowercased(), default: Header(name: name)].addValue(value)
   }
 
-  /// Add values to a header with a given name.
-  ///
-  /// - parameter name:   The name of the header.
-  /// - parameter value: The values to add.
-  mutating func add(name: String, value: [String]) {
-    self.headers[name.lowercased(), default: Header(name: name)].addValue(value)
-  }
-
   /// Set the value of a given header.
   ///
   /// - parameter name:  The name of the header.
diff --git a/test/swift/HeadersContainerTests.swift b/test/swift/HeadersContainerTests.swift
index 394fc38421..d7ecd3b976 100644
--- a/test/swift/HeadersContainerTests.swift
+++ b/test/swift/HeadersContainerTests.swift
@@ -12,7 +12,7 @@ final class HeadersContainerTests: XCTestCase {
     XCTAssertEqual(["A": ["123", "456"]], container.allHeaders())
   }
 
-  func testAddingHeaderValueAddsToListOfHeader() {
+  func testAddingHeaderValueAddsToListOfHeaders() {
     var container = HeadersContainer()
     container.add(name: "x-foo", value: "1")
     container.add(name: "x-foo", value: "2")
@@ -29,21 +29,20 @@ final class HeadersContainerTests: XCTestCase {
     XCTAssertEqual(["x-FOO": ["1", "2"]], container.allHeaders())
   }
 
-  func testAddingHeadersValuesAddsToListOfHeaders() {
+  func testSettingHeaderAddsToListOfHeaders() {
     var container = HeadersContainer()
-    container.add(name: "x-foo", value: ["1", "2"])
-    container.add(name: "x-foo", value: ["3", "4"])
+    container.set(name: "x-foo", value: ["abc"])
 
-    XCTAssertEqual(["1", "2", "3", "4"], container.value(forName: "x-foo"))
+    XCTAssertEqual(["abc"], container.value(forName: "x-foo"))
   }
 
-  func testAddingHeaderValuesIsCaseInsensitiveAndPreservesHeaderNameCasing() {
+  func testSettingHeaderOverridesPreviousHeaderValues() {
     var container = HeadersContainer()
-    container.add(name: "x-FOO", value: ["1", "2"])
-    container.add(name: "x-foo", value: ["3", "4"])
+    container.add(name: "x-FOO", value: "1")
+    container.add(name: "x-foo", value: "2")
+    container.set(name: "x-foo", value: ["3"])
 
-    XCTAssertEqual(["1", "2", "3", "4"], container.value(forName: "x-foo"))
-    XCTAssertEqual(["x-FOO": ["1", "2", "3", "4"]], container.allHeaders())
+    XCTAssertEqual(["3"], container.value(forName: "x-foo"))
   }
 
   func testSettingHeaderToNilRemovesAllOfItsValues() {

From 6d6caf2566f87e5835e2319f555d5bde988be18a Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 08:49:21 -0400
Subject: [PATCH 17/37] small tweaks to docs and description property

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/Headers.swift          | 2 +-
 library/swift/HeadersContainer.swift | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/swift/Headers.swift b/library/swift/Headers.swift
index 9aff6e5b79..f383b2f080 100644
--- a/library/swift/Headers.swift
+++ b/library/swift/Headers.swift
@@ -56,6 +56,6 @@ extension Headers {
 
 extension Headers {
   public override var description: String {
-    return "\(type(of: self)) \(self.container.description)"
+    return "\(type(of: self)) \(self.allHeaders())"
   }
 }
diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index 5a16fcdb3c..dcf4defa12 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -1,7 +1,7 @@
 /// The container which manages the underlying headers map.
 /// It maintains the original casing of passed header names.
 /// It treats headers names as case-insensitive for the purpose
-/// of headers lookup and header name conflict resolutions.
+/// of header lookups and header name conflict resolutions.
 struct HeadersContainer: Equatable {
   private var headers: [String: Header]
 

From cc401343d51b534fcbeaa086c7122302ab64186a Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 09:04:40 -0400
Subject: [PATCH 18/37] simplify code

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersContainer.swift | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index dcf4defa12..8de0291ab4 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -41,12 +41,16 @@ struct HeadersContainer: Equatable {
       /// If a given header name already exists in the processed headers map, check
       /// if the currently processed header name is before the existing header name as
       /// determined by an alphabetical order.
-      if let existing = underlyingHeaders[lowercasedName], existing.name > name {
+      guard let existingHeader = underlyingHeaders[lowercasedName] else {
+        underlyingHeaders[lowercasedName] = Header(name: name, value: value)
+        continue
+      }
+
+      if existingHeader.name > name {
         underlyingHeaders[lowercasedName] =
-          Header(name: name, value: value + existing.value)
+          Header(name: name, value: value + existingHeader.value)
       } else {
-        let `default` = Header(name: underlyingHeaders[lowercasedName]?.name ?? name)
-        underlyingHeaders[lowercasedName, default: `default`].addValue(value)
+        underlyingHeaders[lowercasedName]?.addValue(value)
       }
     }
     self.headers = underlyingHeaders

From eac2d9db00b39267796f33ba060d00ae4116b599 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 10:00:09 -0400
Subject: [PATCH 19/37] Doc updates

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift   | 2 +-
 library/swift/HeadersContainer.swift | 9 ++++++---
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 11679e4fff..b9544b9693 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -89,7 +89,7 @@ public class HeadersBuilder: NSObject {
 
   // Initialize a new builder using the provided headers container.
   ///
-  /// - parameter: The headers container to initialize the receiver with.
+  /// - parameter container: The headers container to initialize the receiver with.
   init(container: HeadersContainer) {
     self.container = container
     super.init()
diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index 8de0291ab4..a7cdf4e099 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -83,16 +83,19 @@ struct HeadersContainer: Equatable {
     self.headers[name.lowercased()] = Header(name: name, value: value)
   }
 
-  /// Returns the value of a given header.
+  /// Get the value for the provided header name.
   ///
-  /// - parameter name: The name of the header to return the value for.
+  /// - parameter name: The case-insensitive header name for which to
+  ///                   get the current value.
   ///
   /// - returns: The value associated with a given header.
   func value(forName name: String) -> [String]? {
     return self.headers[name.lowercased()]?.value
   }
 
-  /// The list of all headers stored by the receiver.
+  /// Return all underlying headers.
+  ///
+  /// - returns: The underlying headers.
   func allHeaders() -> [String: [String]] {
     return Dictionary(uniqueKeysWithValues: self.headers.map { _, value in
       return (value.name, value.value)

From 302db00097643051aa6b38e02c01b5cca2deaa89 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 10:00:23 -0400
Subject: [PATCH 20/37] get rid of todo

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/swift/async_await/ContentView.swift | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/examples/swift/async_await/ContentView.swift b/examples/swift/async_await/ContentView.swift
index 2502352c82..bf1b938a4c 100644
--- a/examples/swift/async_await/ContentView.swift
+++ b/examples/swift/async_await/ContentView.swift
@@ -74,10 +74,8 @@ private extension StreamClient {
             .setOnResponseHeaders { headers, _, _ in
                 let allHeaders = headers.allHeaders()
 
-                if allHeaders[":status"]?.first == "200",
-                   // TODO(jpsim): Expose an API that enforces case-insensitive lookups
-                   let contentLengthValue = allHeaders["Content-Length"] ??
-                                            allHeaders["content-length"],
+                if headers.value(forName: ":status")?.first == "200",
+                   let contentLengthValue = headers.value(forName: "content-length"),
                    let firstContentLength = contentLengthValue.first,
                    let contentLengthInt = Int64(firstContentLength)
                 {

From 9069668063d09b058db7837e931dc713c0bc72c8 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 10:46:12 -0400
Subject: [PATCH 21/37] use case-insensitive comparison

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index b9544b9693..c6139d4cc6 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,8 +3,10 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  let lowercasedName = name.lowercased()
-  return lowercasedName == "host" || kRestrictedPrefixes.contains { lowercasedName.hasPrefix($0) }
+  let isHostHeader = name.range(of: "host", options: [.caseInsensitive]) != nil
+  let hasRestrictedPrefix = kRestrictedPrefixes
+    .contains { name.range(of: $0, options: [.caseInsensitive, .anchored]) != nil }
+  return isHostHeader || hasRestrictedPrefix
 }
 
 /// Base builder class used to construct `Headers` instances.

From 15cb3621fbf2bd302bc316a53860cfe808eae847 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 12:02:32 -0400
Subject: [PATCH 22/37] fix case insensitive comparison and add tests

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/HeadersBuilder.swift                              | 2 +-
 .../io/envoyproxy/envoymobile/RequestHeadersBuilderTest.kt      | 2 ++
 test/swift/HeadersBuilderTests.swift                            | 2 ++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index c6139d4cc6..0e29a65089 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -3,7 +3,7 @@ import Foundation
 private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
-  let isHostHeader = name.range(of: "host", options: [.caseInsensitive]) != nil
+  let isHostHeader = name.caseInsensitiveCompare("host") == .orderedSame
   let hasRestrictedPrefix = kRestrictedPrefixes
     .contains { name.range(of: $0, options: [.caseInsensitive, .anchored]) != nil }
   return isHostHeader || hasRestrictedPrefix
diff --git a/test/kotlin/io/envoyproxy/envoymobile/RequestHeadersBuilderTest.kt b/test/kotlin/io/envoyproxy/envoymobile/RequestHeadersBuilderTest.kt
index 7fb43c3c59..88d0b0f5f1 100644
--- a/test/kotlin/io/envoyproxy/envoymobile/RequestHeadersBuilderTest.kt
+++ b/test/kotlin/io/envoyproxy/envoymobile/RequestHeadersBuilderTest.kt
@@ -100,11 +100,13 @@ class RequestHeadersBuilderTest {
       .add(":x-foo", "123")
       .add("x-envoy-mobile-foo", "abc")
       .add("host", "example.com")
+      .add("hostWithSuffix", "foo.bar")
       .build()
 
     assertThat(headers.allHeaders()).doesNotContainKey(":x-foo")
     assertThat(headers.allHeaders()).doesNotContainKey("x-envoy-mobile-foo")
     assertThat(headers.allHeaders()).doesNotContainKey("host")
+    assertThat(headers.value("hostWithSuffix")).containsExactly("foo.bar")
   }
 
   @Test
diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index 4d08c0c4af..4bf5fdcf30 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -69,6 +69,7 @@ final class HeadersBuilderTests: XCTestCase {
   func testRestrictedHeadersAreNotSettable() {
     let headers = RequestHeadersBuilder(method: .get, authority: "example.com", path: "/")
       .add(name: "host", value: "example.com")
+      .add(name: "hostWithSuffix", value: "foo.bar")
       .set(name: ":scheme", value: ["http"])
       .set(name: ":path", value: ["/nope"])
       .allHeaders()
@@ -77,6 +78,7 @@ final class HeadersBuilderTests: XCTestCase {
       ":path": ["/"],
       ":method": ["GET"],
       ":scheme": ["https"],
+      "hostWithSuffix": ["foo.bar"]
     ]
     XCTAssertEqual(expected, headers)
   }

From ca4441ad5b26e874e6b594c4b3aa0eeb6d2a7b75 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 12:08:51 -0400
Subject: [PATCH 23/37] lint fixes

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 test/swift/HeadersBuilderTests.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/swift/HeadersBuilderTests.swift b/test/swift/HeadersBuilderTests.swift
index 4bf5fdcf30..a92185ad25 100644
--- a/test/swift/HeadersBuilderTests.swift
+++ b/test/swift/HeadersBuilderTests.swift
@@ -78,7 +78,7 @@ final class HeadersBuilderTests: XCTestCase {
       ":path": ["/"],
       ":method": ["GET"],
       ":scheme": ["https"],
-      "hostWithSuffix": ["foo.bar"]
+      "hostWithSuffix": ["foo.bar"],
     ]
     XCTAssertEqual(expected, headers)
   }

From fe79cb3702c3d83531516d8f9b170e920fd3b83e Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 13:12:05 -0400
Subject: [PATCH 24/37] cr comments

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 library/swift/Headers.swift          | 18 ++++++++++-----
 library/swift/Stream.swift           |  4 ++--
 library/swift/filters/Filter.swift   | 34 ++++++++++++++++------------
 library/swift/mocks/MockStream.swift |  5 ++--
 4 files changed, 37 insertions(+), 24 deletions(-)

diff --git a/library/swift/Headers.swift b/library/swift/Headers.swift
index f383b2f080..779b57b940 100644
--- a/library/swift/Headers.swift
+++ b/library/swift/Headers.swift
@@ -8,19 +8,25 @@ public class Headers: NSObject {
 
   /// Get the value for the provided header name.
   ///
-  /// - parameter name: The case-insensitive header name for which to
-  ///                   get the current value.
+  /// - note: The lookup for a header name is a case-insensitive operation.
   ///
+  /// - parameter name: Header name for which to get the current value.
   ///
   /// - returns: The current headers specified for the provided name.
   public func value(forName name: String) -> [String]? {
     return self.container.value(forName: name)
   }
 
-  /// Accessor for all underlying headers as a map.
+  /// Accessor for all underlying case-sensitive headers. When possible,
+  /// use case-insensitive accessors instead.
   ///
-  /// - returns: The underlying headers.
-  public func allHeaders() -> [String: [String]] {
+  /// - warning: It's discouraged to use this dictionary for equality
+  ///            key-based lookups as this may lead to issues with headers
+  ///            that do not follow expected casing i.e., "Content-Length"
+  ///            instead of "content-length".
+  ///
+  /// - returns: The underlying case-sensitive headers.
+  public func caseSensitiveHeaders() -> [String: [String]] {
     return self.container.allHeaders()
   }
 
@@ -56,6 +62,6 @@ extension Headers {
 
 extension Headers {
   public override var description: String {
-    return "\(type(of: self)) \(self.allHeaders())"
+    return "\(type(of: self)) \(self.caseSensitiveHeaders())"
   }
 }
diff --git a/library/swift/Stream.swift b/library/swift/Stream.swift
index 0a0e8ddc0a..8be28f14cb 100644
--- a/library/swift/Stream.swift
+++ b/library/swift/Stream.swift
@@ -26,7 +26,7 @@ public class Stream: NSObject {
   /// - returns: This stream, for chaining syntax.
   @discardableResult
   public func sendHeaders(_ headers: RequestHeaders, endStream: Bool) -> Stream {
-    self.underlyingStream.sendHeaders(headers.allHeaders(), close: endStream)
+    self.underlyingStream.sendHeaders(headers.caseSensitiveHeaders(), close: endStream)
     return self
   }
 
@@ -57,7 +57,7 @@ public class Stream: NSObject {
   ///
   /// - parameter trailers: Trailers with which to close the stream.
   public func close(trailers: RequestTrailers) {
-    self.underlyingStream.sendTrailers(trailers.allHeaders())
+    self.underlyingStream.sendTrailers(trailers.caseSensitiveHeaders())
   }
 
   /// Close the stream with a data frame.
diff --git a/library/swift/filters/Filter.swift b/library/swift/filters/Filter.swift
index 8835fbc078..4bce1feafd 100644
--- a/library/swift/filters/Filter.swift
+++ b/library/swift/filters/Filter.swift
@@ -27,7 +27,7 @@ extension EnvoyHTTPFilter {
                                                     streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let headers):
-          return [kEnvoyFilterHeadersStatusContinue, headers.allHeaders()]
+          return [kEnvoyFilterHeadersStatusContinue, headers.caseSensitiveHeaders()]
         case .stopIteration:
           return [kEnvoyFilterHeadersStatusStopIteration, NSNull()]
         }
@@ -44,7 +44,10 @@ extension EnvoyHTTPFilter {
         case .stopIterationNoBuffer:
           return [kEnvoyFilterDataStatusStopIterationNoBuffer, NSNull()]
         case .resumeIteration(let headers, let data):
-          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.allHeaders() as Any]
+          return [
+                    kEnvoyFilterDataStatusResumeIteration, data,
+                    headers?.caseSensitiveHeaders() as Any,
+          ]
         }
       }
 
@@ -53,14 +56,14 @@ extension EnvoyHTTPFilter {
                                                      streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let trailers):
-          return [kEnvoyFilterTrailersStatusContinue, trailers.allHeaders()]
+          return [kEnvoyFilterTrailersStatusContinue, trailers.caseSensitiveHeaders()]
         case .stopIteration:
           return [kEnvoyFilterTrailersStatusStopIteration, NSNull()]
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterTrailersStatusResumeIteration,
-            trailers.allHeaders(),
-            headers?.allHeaders() as Any,
+            trailers.caseSensitiveHeaders(),
+            headers?.caseSensitiveHeaders() as Any,
             data as Any,
           ]
         }
@@ -74,7 +77,7 @@ extension EnvoyHTTPFilter {
                                                       streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let headers):
-          return [kEnvoyFilterHeadersStatusContinue, headers.allHeaders()]
+          return [kEnvoyFilterHeadersStatusContinue, headers.caseSensitiveHeaders()]
         case .stopIteration:
           return [kEnvoyFilterHeadersStatusStopIteration, NSNull()]
         }
@@ -91,7 +94,10 @@ extension EnvoyHTTPFilter {
         case .stopIterationNoBuffer:
           return [kEnvoyFilterDataStatusStopIterationNoBuffer, NSNull()]
         case .resumeIteration(let headers, let data):
-          return [kEnvoyFilterDataStatusResumeIteration, data, headers?.allHeaders() as Any]
+          return [
+                    kEnvoyFilterDataStatusResumeIteration, data,
+                    headers?.caseSensitiveHeaders() as Any,
+          ]
         }
       }
 
@@ -100,14 +106,14 @@ extension EnvoyHTTPFilter {
                                                        streamIntel: StreamIntel(streamIntel))
         switch result {
         case .continue(let trailers):
-          return [kEnvoyFilterTrailersStatusContinue, trailers.allHeaders()]
+          return [kEnvoyFilterTrailersStatusContinue, trailers.caseSensitiveHeaders()]
         case .stopIteration:
           return [kEnvoyFilterTrailersStatusStopIteration, NSNull()]
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterTrailersStatusResumeIteration,
-            trailers.allHeaders(),
-            headers?.allHeaders() as Any,
+            trailers.caseSensitiveHeaders(),
+            headers?.caseSensitiveHeaders() as Any,
             data as Any,
           ]
         }
@@ -146,9 +152,9 @@ extension EnvoyHTTPFilter {
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterResumeStatusResumeIteration,
-            headers?.allHeaders() as Any,
+            headers?.caseSensitiveHeaders() as Any,
             data as Any,
-            trailers?.allHeaders() as Any,
+            trailers?.caseSensitiveHeaders() as Any,
           ]
         }
       }
@@ -172,9 +178,9 @@ extension EnvoyHTTPFilter {
         case .resumeIteration(let headers, let data, let trailers):
           return [
             kEnvoyFilterResumeStatusResumeIteration,
-            headers?.allHeaders() as Any,
+            headers?.caseSensitiveHeaders() as Any,
             data as Any,
-            trailers?.allHeaders() as Any,
+            trailers?.caseSensitiveHeaders() as Any,
           ]
         }
       }
diff --git a/library/swift/mocks/MockStream.swift b/library/swift/mocks/MockStream.swift
index d383d62d78..4bbd3fcadb 100644
--- a/library/swift/mocks/MockStream.swift
+++ b/library/swift/mocks/MockStream.swift
@@ -52,7 +52,8 @@ public final class MockStream: Stream {
   /// - parameter headers:   Response headers to receive.
   /// - parameter endStream: Whether this is a headers-only response.
   public func receiveHeaders(_ headers: ResponseHeaders, endStream: Bool) {
-    self.mockStream.callbacks.onHeaders(headers.allHeaders(), endStream, EnvoyStreamIntel())
+    self.mockStream.callbacks.onHeaders(headers.caseSensitiveHeaders(), endStream,
+                                        EnvoyStreamIntel())
   }
 
   /// Simulate response data coming back over the stream.
@@ -67,7 +68,7 @@ public final class MockStream: Stream {
   ///
   /// - parameter trailers: Response trailers to receive.
   public func receiveTrailers(_ trailers: ResponseTrailers) {
-    self.mockStream.callbacks.onTrailers(trailers.allHeaders(), EnvoyStreamIntel())
+    self.mockStream.callbacks.onTrailers(trailers.caseSensitiveHeaders(), EnvoyStreamIntel())
   }
 
   /// Simulate the stream receiving a cancellation signal from Envoy.

From a80ef6a2d6d676fc6b487d1335a91727df3348b1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Augustyniak?=
 <Augustyniak@users.noreply.github.com>
Date: Tue, 28 Jun 2022 13:13:00 -0400
Subject: [PATCH 25/37] Update library/swift/HeadersBuilder.swift
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: JP Simard <jp@jpsim.com>

Signed-off-by: Rafał Augustyniak <Augustyniak@users.noreply.github.com>
---
 library/swift/HeadersBuilder.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 0e29a65089..2851187bba 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -11,7 +11,7 @@ private func isRestrictedHeader(name: String) -> Bool {
 
 /// Base builder class used to construct `Headers` instances.
 /// It preserves the original casing of headers and enforces
-/// a case-insensitive look up and setting of headers.
+/// a case-insensitive lookup and setting of headers.
 /// See `{Request|Response}HeadersBuilder` for usage.
 @objcMembers
 public class HeadersBuilder: NSObject {

From 1a4d9150f5345d64c7be7302c38fdfb34b7c44f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Augustyniak?=
 <Augustyniak@users.noreply.github.com>
Date: Tue, 28 Jun 2022 13:13:12 -0400
Subject: [PATCH 26/37] Update library/swift/HeadersContainer.swift
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: JP Simard <jp@jpsim.com>

Signed-off-by: Rafał Augustyniak <Augustyniak@users.noreply.github.com>
---
 library/swift/HeadersContainer.swift | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index a7cdf4e099..fcecc61a68 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -5,8 +5,8 @@
 struct HeadersContainer: Equatable {
   private var headers: [String: Header]
 
-  // Represents a headers name together with all of its values.
-  // It preserves the original casing of the header name.
+  /// Represents a headers name together with all of its values.
+  /// It preserves the original casing of the header name.
   struct Header: Equatable {
     private(set) var name: String
     private(set) var value: [String]

From 2a5085a0dd632d7f5a4787e8f00bb8d706bc40d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Augustyniak?=
 <Augustyniak@users.noreply.github.com>
Date: Tue, 28 Jun 2022 13:13:22 -0400
Subject: [PATCH 27/37] Update library/swift/HeadersContainer.swift
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: JP Simard <jp@jpsim.com>

Signed-off-by: Rafał Augustyniak <Augustyniak@users.noreply.github.com>
---
 library/swift/HeadersContainer.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/swift/HeadersContainer.swift b/library/swift/HeadersContainer.swift
index fcecc61a68..2f2e631348 100644
--- a/library/swift/HeadersContainer.swift
+++ b/library/swift/HeadersContainer.swift
@@ -34,7 +34,7 @@ struct HeadersContainer: Equatable {
       let lowercasedName = name.lowercased()
       /// Dictionaries in Swift are unordered collections. Process headers with names
       /// that are the same when lowercased in an alphabetical order to avoid a situation
-      /// in which the result of the initialization is underministic i.e., we want
+      /// in which the result of the initialization is non-derministic i.e., we want
       /// "[A: ["1"]", "a: ["2"]]" headers to be always converted to ["A": ["1", "2"]] and
       /// never to "a": ["2", "1"].
       ///

From b9d1dd9ab5ca6f26eba8d6f64857bc36c9c161e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Augustyniak?=
 <Augustyniak@users.noreply.github.com>
Date: Tue, 28 Jun 2022 13:20:10 -0400
Subject: [PATCH 28/37] Update library/swift/HeadersBuilder.swift
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: JP Simard <jp@jpsim.com>

Signed-off-by: Rafał Augustyniak <Augustyniak@users.noreply.github.com>
---
 library/swift/HeadersBuilder.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/swift/HeadersBuilder.swift b/library/swift/HeadersBuilder.swift
index 2851187bba..b245f3aee5 100644
--- a/library/swift/HeadersBuilder.swift
+++ b/library/swift/HeadersBuilder.swift
@@ -4,7 +4,7 @@ private let kRestrictedPrefixes = [":", "x-envoy-mobile"]
 
 private func isRestrictedHeader(name: String) -> Bool {
   let isHostHeader = name.caseInsensitiveCompare("host") == .orderedSame
-  let hasRestrictedPrefix = kRestrictedPrefixes
+  lazy var hasRestrictedPrefix = kRestrictedPrefixes
     .contains { name.range(of: $0, options: [.caseInsensitive, .anchored]) != nil }
   return isHostHeader || hasRestrictedPrefix
 }

From 75a586df0f47b99758da704028cec8f729155b85 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 13:25:15 -0400
Subject: [PATCH 29/37] update version history

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 docs/root/intro/version_history.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/root/intro/version_history.rst b/docs/root/intro/version_history.rst
index 2fdf016ac9..819ccd3e9c 100644
--- a/docs/root/intro/version_history.rst
+++ b/docs/root/intro/version_history.rst
@@ -24,7 +24,7 @@ Bugfixes:
 - Android: update Kotlin standard libraries to 1.6.21 (:issue:`#2256 <2256>`)
 - fix bug where finalStreamIntel was not consistently set on cancel (:issue:`#2285 <2285>`)
 - iOS: fix termination crash in ProvisionalDispatcher (:issue:`#2059 <2059>`)
-- iOS: make headers lookup in ``HeadersBuilder`` and ``Headers`` case-insensitive (:issue:`#2383 <2383>`)
+- iOS: make headers lookup in ``HeadersBuilder`` and ``Headers`` case-insensitive. Rename ``allHeaders`` method to ``caseSensitiveHeaders``. (:issue:`#2383 <2383>`)
 - iOS: use correct DNS resolver when using C++ config builder (:issue: `#2378 <2378 >`)
 
 Features:

From 7295362d1efea3a930383d283ff3d2b9eb5448f6 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 14:37:43 -0400
Subject: [PATCH 30/37] change used method

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/swift/async_await/ContentView.swift      | 2 --
 examples/swift/hello_world/ViewController.swift   | 2 +-
 test/swift/apps/experimental/ViewController.swift | 2 +-
 3 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/examples/swift/async_await/ContentView.swift b/examples/swift/async_await/ContentView.swift
index bf1b938a4c..8b8ade46bc 100644
--- a/examples/swift/async_await/ContentView.swift
+++ b/examples/swift/async_await/ContentView.swift
@@ -72,8 +72,6 @@ private extension StreamClient {
         let stream = self
             .newStreamPrototype()
             .setOnResponseHeaders { headers, _, _ in
-                let allHeaders = headers.allHeaders()
-
                 if headers.value(forName: ":status")?.first == "200",
                    let contentLengthValue = headers.value(forName: "content-length"),
                    let firstContentLength = contentLengthValue.first,
diff --git a/examples/swift/hello_world/ViewController.swift b/examples/swift/hello_world/ViewController.swift
index 8676c01002..f9f998e65d 100644
--- a/examples/swift/hello_world/ViewController.swift
+++ b/examples/swift/hello_world/ViewController.swift
@@ -70,7 +70,7 @@ final class ViewController: UITableViewController {
         let statusCode = headers.httpStatus.map(String.init) ?? "nil"
         let message = "received headers with status \(statusCode)"
 
-        let headerMessage = headers.allHeaders()
+        let headerMessage = headers.caseSensitiveHeaders()
           .filter { kFilteredHeaders.contains($0.key) }
           .map { "\($0.key): \($0.value.joined(separator: ", "))" }
           .joined(separator: "\n")
diff --git a/test/swift/apps/experimental/ViewController.swift b/test/swift/apps/experimental/ViewController.swift
index 59644895ed..02f043617a 100644
--- a/test/swift/apps/experimental/ViewController.swift
+++ b/test/swift/apps/experimental/ViewController.swift
@@ -72,7 +72,7 @@ final class ViewController: UITableViewController {
         let statusCode = headers.httpStatus.map(String.init) ?? "nil"
         let message = "received headers with status \(statusCode)"
 
-        let headerMessage = headers.allHeaders()
+        let headerMessage = headers.caseSensitiveHeaders()
           .filter { kFilteredHeaders.contains($0.key) }
           .map { "\($0.key): \($0.value.joined(separator: ", "))" }
           .joined(separator: "\n")

From 723c76ff46e76f78de210a0d318a50cfc3003132 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 14:50:30 -0400
Subject: [PATCH 31/37] update example app

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 test/swift/apps/baseline/ViewController.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/swift/apps/baseline/ViewController.swift b/test/swift/apps/baseline/ViewController.swift
index 8676c01002..f9f998e65d 100644
--- a/test/swift/apps/baseline/ViewController.swift
+++ b/test/swift/apps/baseline/ViewController.swift
@@ -70,7 +70,7 @@ final class ViewController: UITableViewController {
         let statusCode = headers.httpStatus.map(String.init) ?? "nil"
         let message = "received headers with status \(statusCode)"
 
-        let headerMessage = headers.allHeaders()
+        let headerMessage = headers.caseSensitiveHeaders()
           .filter { kFilteredHeaders.contains($0.key) }
           .map { "\($0.key): \($0.value.joined(separator: ", "))" }
           .joined(separator: "\n")

From 079a01a8b62988bc21152d16fa0965626b5aae8e Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 15:16:32 -0400
Subject: [PATCH 32/37] update example app

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/swift/async_await/ContentView.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/swift/async_await/ContentView.swift b/examples/swift/async_await/ContentView.swift
index 8b8ade46bc..0931c531bc 100644
--- a/examples/swift/async_await/ContentView.swift
+++ b/examples/swift/async_await/ContentView.swift
@@ -83,7 +83,7 @@ private extension StreamClient {
                     return
                 }
 
-                let headerMessage = allHeaders
+                let headerMessage = caseSensitiveHeaders
                     .map { "\($0.key): \($0.value.joined(separator: ", "))" }
                     .joined(separator: "\n")
 

From 62885af9da93ff5b5792f8f2cbb7f1823012d341 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 15:30:49 -0400
Subject: [PATCH 33/37] update example app

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/swift/async_await/ContentView.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/swift/async_await/ContentView.swift b/examples/swift/async_await/ContentView.swift
index 0931c531bc..e510e8d0b8 100644
--- a/examples/swift/async_await/ContentView.swift
+++ b/examples/swift/async_await/ContentView.swift
@@ -83,7 +83,7 @@ private extension StreamClient {
                     return
                 }
 
-                let headerMessage = caseSensitiveHeaders
+                let headerMessage = headers.caseSensitiveHeaders
                     .map { "\($0.key): \($0.value.joined(separator: ", "))" }
                     .joined(separator: "\n")
 

From 702bc24d51c109d1507267bdb277e64730ad6b7b Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 15:53:43 -0400
Subject: [PATCH 34/37] update example apps

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/objective-c/hello_world/ViewController.m |  4 ++--
 examples/swift/async_await/ContentView.swift      |  2 +-
 test/swift/apps/experimental/ViewController.swift | 11 ++++++++---
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/examples/objective-c/hello_world/ViewController.m b/examples/objective-c/hello_world/ViewController.m
index 3a989e42cf..69e16bc5d4 100644
--- a/examples/objective-c/hello_world/ViewController.m
+++ b/examples/objective-c/hello_world/ViewController.m
@@ -90,9 +90,9 @@ - (void)performRequest {
     NSString *message = [NSString stringWithFormat:@"received headers with status %i", statusCode];
 
     NSMutableString *headerMessage = [NSMutableString new];
-    for (NSString *name in headers.allHeaders) {
+    for (NSString *name in headers.caseSensitiveHeaders()) {
       if ([self.filteredHeaders containsObject:name]) {
-        NSArray<NSString *> *values = headers.allHeaders[name];
+        NSArray<NSString *> *values = headers.caseSensitiveHeaders()[name];
         NSString *joined = [values componentsJoinedByString:@", "];
         NSString *pair = [NSString stringWithFormat:@"%@: %@\n", name, joined];
         [headerMessage appendString:pair];
diff --git a/examples/swift/async_await/ContentView.swift b/examples/swift/async_await/ContentView.swift
index e510e8d0b8..6772ecbf5c 100644
--- a/examples/swift/async_await/ContentView.swift
+++ b/examples/swift/async_await/ContentView.swift
@@ -83,7 +83,7 @@ private extension StreamClient {
                     return
                 }
 
-                let headerMessage = headers.caseSensitiveHeaders
+                let headerMessage = headers.caseSensitiveHeaders()
                     .map { "\($0.key): \($0.value.joined(separator: ", "))" }
                     .joined(separator: "\n")
 
diff --git a/test/swift/apps/experimental/ViewController.swift b/test/swift/apps/experimental/ViewController.swift
index 02f043617a..f2e8fe2f94 100644
--- a/test/swift/apps/experimental/ViewController.swift
+++ b/test/swift/apps/experimental/ViewController.swift
@@ -72,9 +72,14 @@ final class ViewController: UITableViewController {
         let statusCode = headers.httpStatus.map(String.init) ?? "nil"
         let message = "received headers with status \(statusCode)"
 
-        let headerMessage = headers.caseSensitiveHeaders()
-          .filter { kFilteredHeaders.contains($0.key) }
-          .map { "\($0.key): \($0.value.joined(separator: ", "))" }
+        let headerMessage = kFilteredHeaders
+          .compactMap { name in 
+              guard let value = headers.value(forName: $0) else {
+                return nil
+              }
+
+              return "\($0.key): \($0.value.joined(separator: ", "))"
+           }
           .joined(separator: "\n")
 
         NSLog(message)

From d3bd1ea913db9de227005ebc047f5cefa541d4c4 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 15:57:12 -0400
Subject: [PATCH 35/37] update example apps

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 test/swift/apps/experimental/ViewController.swift | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/swift/apps/experimental/ViewController.swift b/test/swift/apps/experimental/ViewController.swift
index f2e8fe2f94..a6141ffb8d 100644
--- a/test/swift/apps/experimental/ViewController.swift
+++ b/test/swift/apps/experimental/ViewController.swift
@@ -73,7 +73,7 @@ final class ViewController: UITableViewController {
         let message = "received headers with status \(statusCode)"
 
         let headerMessage = kFilteredHeaders
-          .compactMap { name in 
+          .compactMap { name in
               guard let value = headers.value(forName: $0) else {
                 return nil
               }

From d45fa9f8fbf2567126aab1327cf4339f43409b0e Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 15:57:50 -0400
Subject: [PATCH 36/37] update example apps

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 test/swift/apps/experimental/ViewController.swift | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/test/swift/apps/experimental/ViewController.swift b/test/swift/apps/experimental/ViewController.swift
index a6141ffb8d..02f043617a 100644
--- a/test/swift/apps/experimental/ViewController.swift
+++ b/test/swift/apps/experimental/ViewController.swift
@@ -72,14 +72,9 @@ final class ViewController: UITableViewController {
         let statusCode = headers.httpStatus.map(String.init) ?? "nil"
         let message = "received headers with status \(statusCode)"
 
-        let headerMessage = kFilteredHeaders
-          .compactMap { name in
-              guard let value = headers.value(forName: $0) else {
-                return nil
-              }
-
-              return "\($0.key): \($0.value.joined(separator: ", "))"
-           }
+        let headerMessage = headers.caseSensitiveHeaders()
+          .filter { kFilteredHeaders.contains($0.key) }
+          .map { "\($0.key): \($0.value.joined(separator: ", "))" }
           .joined(separator: "\n")
 
         NSLog(message)

From 42b38bf8ee16f7267774bb580717b7b487108a46 Mon Sep 17 00:00:00 2001
From: Rafal Augustyniak <raugustyniak@lyft.com>
Date: Tue, 28 Jun 2022 16:21:14 -0400
Subject: [PATCH 37/37] update example apps

Signed-off-by: Rafal Augustyniak <raugustyniak@lyft.com>
---
 examples/objective-c/hello_world/ViewController.m | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/examples/objective-c/hello_world/ViewController.m b/examples/objective-c/hello_world/ViewController.m
index 69e16bc5d4..d01dd8a750 100644
--- a/examples/objective-c/hello_world/ViewController.m
+++ b/examples/objective-c/hello_world/ViewController.m
@@ -90,9 +90,9 @@ - (void)performRequest {
     NSString *message = [NSString stringWithFormat:@"received headers with status %i", statusCode];
 
     NSMutableString *headerMessage = [NSMutableString new];
-    for (NSString *name in headers.caseSensitiveHeaders()) {
+    for (NSString *name in headers.caseSensitiveHeaders) {
       if ([self.filteredHeaders containsObject:name]) {
-        NSArray<NSString *> *values = headers.caseSensitiveHeaders()[name];
+        NSArray<NSString *> *values = headers.caseSensitiveHeaders[name];
         NSString *joined = [values componentsJoinedByString:@", "];
         NSString *pair = [NSString stringWithFormat:@"%@: %@\n", name, joined];
         [headerMessage appendString:pair];