filters: add generic compressor filter

CODEOWNERS

@@ -18,6 +18,8 @@ extensions/filters/common/original_src @snowp @klarose
 /*/extensions/filters/network/dubbo_proxy @zyfjeff @lizan
 # thrift_proxy extension
 /*/extensions/filters/network/thrift_proxy @zuercher @brian-pane
+# compressor used by http compression filters
+/*/extensions/filters/http/common/compressor @gsagula @rojkov @dio
 # jwt_authn http filter extension
 /*/extensions/filters/http/jwt_authn @qiwzhang @lizan
 # grpc_http1_reverse_bridge http filter extension

api/docs/BUILD

@@ -31,6 +31,7 @@ proto_library(
         "//envoy/config/filter/fault/v2:pkg",
         "//envoy/config/filter/http/adaptive_concurrency/v2alpha:pkg",
         "//envoy/config/filter/http/buffer/v2:pkg",
+        "//envoy/config/filter/http/compressor/v2:pkg",
         "//envoy/config/filter/http/csrf/v2:pkg",
         "//envoy/config/filter/http/dynamic_forward_proxy/v2alpha:pkg",
         "//envoy/config/filter/http/ext_authz/v2:pkg",

api/envoy/config/filter/http/compressor/v2/BUILD

@@ -0,0 +1,7 @@
+# DO NOT EDIT. This file is generated by tools/proto_sync.py.
+
+load("@envoy_api//bazel:api_build_system.bzl", "api_proto_package")
+
+licenses(["notice"])  # Apache 2
+
+api_proto_package()

api/envoy/config/filter/http/compressor/v2/compressor.proto

@@ -0,0 +1,30 @@
+syntax = "proto3";
+
+package envoy.config.filter.http.compressor.v2;
+
+option java_outer_classname = "CompressorProto";
+option java_multiple_files = true;
+option java_package = "io.envoyproxy.envoy.config.filter.http.compressor.v2";
+
+import "google/protobuf/wrappers.proto";
+
+// [#protodoc-title: Compressor]
+
+message Compressor {
+  // Minimum response length, in bytes, which will trigger compression. The default value is 30.
+  google.protobuf.UInt32Value content_length = 1;
+
+  // Set of strings that allows specifying which mime-types yield compression; e.g.,
+  // application/json, text/html, etc. When this field is not defined, compression will be applied
+  // to the following mime-types: "application/javascript", "application/json",
+  // "application/xhtml+xml", "image/svg+xml", "text/css", "text/html", "text/plain", "text/xml".
+  repeated string content_type = 2;
+
+  // If true, disables compression when the response contains an etag header. When it is false, the
+  // filter will preserve weak etags and remove the ones that require strong validation.
+  bool disable_on_etag_header = 3;
+
+  // If true, removes accept-encoding from the request headers before dispatching it to the upstream
+  // so that responses do not get compressed before reaching the filter.
+  bool remove_accept_encoding_header = 4;
+}

api/envoy/config/filter/http/gzip/v2/BUILD

@@ -4,4 +4,6 @@ load("@envoy_api//bazel:api_build_system.bzl", "api_proto_package")
 
 licenses(["notice"])  # Apache 2
 
-api_proto_package()
+api_proto_package(
+    deps = ["//envoy/config/filter/http/compressor/v2:pkg"],
+)

api/envoy/config/filter/http/gzip/v2/gzip.proto

@@ -6,14 +6,16 @@ option java_outer_classname = "GzipProto";
 option java_multiple_files = true;
 option java_package = "io.envoyproxy.envoy.config.filter.http.gzip.v2";
 
+import "envoy/config/filter/http/compressor/v2/compressor.proto";
+
 import "google/protobuf/wrappers.proto";
 
 import "validate/validate.proto";
 
 // [#protodoc-title: Gzip]
 // Gzip :ref:`configuration overview <config_http_filters_gzip>`.
 
-// [#next-free-field: 10]
+// [#next-free-field: 11]
 message Gzip {
   enum CompressionStrategy {
     DEFAULT = 0;
@@ -35,7 +37,10 @@ message Gzip {
   google.protobuf.UInt32Value memory_level = 1 [(validate.rules).uint32 = {lte: 9 gte: 1}];
 
   // Minimum response length, in bytes, which will trigger compression. The default value is 30.
-  google.protobuf.UInt32Value content_length = 2 [(validate.rules).uint32 = {gte: 30}];
+  // .. attention:
+  //
+  //    **This field is deprecated**. Set the `compressor` field instead.
+  google.protobuf.UInt32Value content_length = 2 [deprecated = true];
 
   // A value used for selecting the zlib compression level. This setting will affect speed and
   // amount of compression applied to the content. "BEST" provides higher compression at the cost of
@@ -56,19 +61,33 @@ message Gzip {
   // application/json, text/html, etc. When this field is not defined, compression will be applied
   // to the following mime-types: "application/javascript", "application/json",
   // "application/xhtml+xml", "image/svg+xml", "text/css", "text/html", "text/plain", "text/xml".
-  repeated string content_type = 6 [(validate.rules).repeated = {max_items: 50}];
+  // .. attention:
+  //
+  //    **This field is deprecated**. Set the `compressor` field instead.
+  repeated string content_type = 6 [deprecated = true];
 
   // If true, disables compression when the response contains an etag header. When it is false, the
   // filter will preserve weak etags and remove the ones that require strong validation.
-  bool disable_on_etag_header = 7;
+  // .. attention:
+  //
+  //    **This field is deprecated**. Set the `compressor` field instead.
+  bool disable_on_etag_header = 7 [deprecated = true];
 
   // If true, removes accept-encoding from the request headers before dispatching it to the upstream
   // so that responses do not get compressed before reaching the filter.
-  bool remove_accept_encoding_header = 8;
+  // .. attention:
+  //
+  //    **This field is deprecated**. Set the `compressor` field instead.
+  bool remove_accept_encoding_header = 8 [deprecated = true];
 
   // Value from 9 to 15 that represents the base two logarithmic of the compressor's window size.
   // Larger window results in better compression at the expense of memory usage. The default is 12
   // which will produce a 4096 bytes window. For more details about this parameter, please refer to
   // zlib manual > deflateInit2.
   google.protobuf.UInt32Value window_bits = 9 [(validate.rules).uint32 = {lte: 15 gte: 9}];
+
+  // Set of configuration parameters common for all compression filters. If this field is set then
+  // the fields `content_length`, `content_type`, `disable_on_etag_header` and
+  // `remove_accept_encoding_header` are ignored.
+  compressor.v2.Compressor compressor = 10;
 }

api/envoy/config/filter/http/gzip/v3alpha/BUILD

@@ -0,0 +1,9 @@
+# DO NOT EDIT. This file is generated by tools/proto_sync.py.
+
+load("@envoy_api//bazel:api_build_system.bzl", "api_proto_package")
+
+licenses(["notice"])  # Apache 2
+
+api_proto_package(
+    deps = ["//envoy/config/filter/http/compressor/v2:pkg"],
+)

api/envoy/config/filter/http/gzip/v3alpha/gzip.proto

@@ -0,0 +1,69 @@
+syntax = "proto3";
+
+package envoy.config.filter.http.gzip.v3alpha;
+
+option java_outer_classname = "GzipProto";
+option java_multiple_files = true;
+option java_package = "io.envoyproxy.envoy.config.filter.http.gzip.v3alpha";
+
+import "envoy/config/filter/http/compressor/v2/compressor.proto";
+
+import "google/protobuf/wrappers.proto";
+
+import "validate/validate.proto";
+
+// [#protodoc-title: Gzip]
+// Gzip :ref:`configuration overview <config_http_filters_gzip>`.
+
+// [#next-free-field: 11]
+message Gzip {
+  enum CompressionStrategy {
+    DEFAULT = 0;
+    FILTERED = 1;
+    HUFFMAN = 2;
+    RLE = 3;
+  }
+
+  message CompressionLevel {
+    enum Enum {
+      DEFAULT = 0;
+      BEST = 1;
+      SPEED = 2;
+    }
+  }
+
+  reserved 2, 6, 7, 8;
+
+  reserved "content_length", "content_type", "disable_on_etag_header",
+      "remove_accept_encoding_header";
+
+  // Value from 1 to 9 that controls the amount of internal memory used by zlib. Higher values
+  // use more memory, but are faster and produce better compression results. The default value is 5.
+  google.protobuf.UInt32Value memory_level = 1 [(validate.rules).uint32 = {lte: 9 gte: 1}];
+
+  // A value used for selecting the zlib compression level. This setting will affect speed and
+  // amount of compression applied to the content. "BEST" provides higher compression at the cost of
+  // higher latency, "SPEED" provides lower compression with minimum impact on response time.
+  // "DEFAULT" provides an optimal result between speed and compression. This field will be set to
+  // "DEFAULT" if not specified.
+  CompressionLevel.Enum compression_level = 3 [(validate.rules).enum = {defined_only: true}];
+
+  // A value used for selecting the zlib compression strategy which is directly related to the
+  // characteristics of the content. Most of the time "DEFAULT" will be the best choice, though
+  // there are situations which changing this parameter might produce better results. For example,
+  // run-length encoding (RLE) is typically used when the content is known for having sequences
+  // which same data occurs many consecutive times. For more information about each strategy, please
+  // refer to zlib manual.
+  CompressionStrategy compression_strategy = 4 [(validate.rules).enum = {defined_only: true}];
+
+  // Value from 9 to 15 that represents the base two logarithmic of the compressor's window size.
+  // Larger window results in better compression at the expense of memory usage. The default is 12
+  // which will produce a 4096 bytes window. For more details about this parameter, please refer to
+  // zlib manual > deflateInit2.
+  google.protobuf.UInt32Value window_bits = 9 [(validate.rules).uint32 = {lte: 15 gte: 9}];
+
+  // Set of configuration parameters common for all compression filters. If this field is set then
+  // the fields `content_length`, `content_type`, `disable_on_etag_header` and
+  // `remove_accept_encoding_header` are ignored.
+  compressor.v2.Compressor compressor = 10;
+}

docs/root/configuration/http/http_filters/gzip_filter.rst

@@ -45,7 +45,8 @@ By *default* compression will be *skipped* when:
   that the "gzip" will have a higher weight then "\*". For example, if *accept-encoding*
   is "gzip;q=0,\*;q=1", the filter will not compress. But if the header is set to
   "\*;q=0,gzip;q=1", the filter will compress.
-- A request whose *accept-encoding* header includes "identity".
+- A request whose *accept-encoding* header includes any encoding type with a higher
+  weight than "gzip"'s.
 - A response contains a *content-encoding* header.
 - A response contains a *cache-control* header whose value includes "no-transform".
 - A response contains a *transfer-encoding* header whose value includes "gzip".
@@ -80,7 +81,9 @@ Every configured Gzip filter has statistics rooted at <stat_prefix>.gzip.* with
   not_compressed, Counter, Number of requests not compressed.
   no_accept_header, Counter, Number of requests with no accept header sent.
   header_identity, Counter, Number of requests sent with "identity" set as the *accept-encoding*.
-  header_gzip, Counter, Number of requests sent with "gzip" set as the *accept-encoding*.
+  header_gzip, Counter, Number of requests sent with "gzip" set as the *accept-encoding*. This counter is deprecated in favour of *header_compressor_used*.
+  header_compressor_used, Counter, Number of requests sent with "gzip" set as the *accept-encoding*.
+  header_compressor_overshadowed, Counter, Number of requests sent with encoding types other than "gzip" and "identity" set as the *accept-encoding*.
   header_wildcard, Counter, Number of requests sent with "\*" set as the *accept-encoding*.
   header_not_valid, Counter, Number of requests sent with a not valid *accept-encoding* header (aka "q=0" or an unsupported encoding type).
   total_uncompressed_bytes, Counter, The total uncompressed bytes of all the requests that were marked for compression.

source/extensions/filters/http/common/compressor/BUILD

@@ -0,0 +1,28 @@
+licenses(["notice"])  # Apache 2
+
+load(
+    "//bazel:envoy_build_system.bzl",
+    "envoy_cc_library",
+    "envoy_package",
+)
+
+envoy_package()
+
+envoy_cc_library(
+    name = "compressor_lib",
+    srcs = ["compressor.cc"],
+    hdrs = ["compressor.h"],
+    deps = [
+        "//include/envoy/compressor:compressor_interface",
+        "//include/envoy/http:filter_interface",
+        "//include/envoy/runtime:runtime_interface",
+        "//include/envoy/stats:stats_macros",
+        "//include/envoy/stream_info:filter_state_interface",
+        "//source/common/buffer:buffer_lib",
+        "//source/common/common:lock_guard_lib",
+        "//source/common/common:thread_lib",
+        "//source/common/http:header_map_lib",
+        "//source/common/protobuf",
+        "@envoy_api//envoy/config/filter/http/compressor/v2:pkg_cc_proto",
+    ],
+)