From cc686177d205192d30010e48cbf614fb4133986a Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 26 Jan 2024 13:52:23 +0800
Subject: [PATCH 01/16] Add GetRehydrationToken to Operation for rehydration
 purpose

---
 eng/Directory.Build.Common.targets            |   1 +
 sdk/core/Azure.Core/src/Azure.Core.csproj     |   8 +-
 sdk/core/Azure.Core/src/Operation.cs          |   5 +
 .../src/RehydrationToken.Serialization.cs     | 135 ++++++++++++++++++
 sdk/core/Azure.Core/src/RehydrationToken.cs   |  53 +++++++
 .../Azure.Core/src/Shared/HeaderSource.cs     |  13 ++
 .../Shared/NextLinkOperationImplementation.cs |   8 --
 .../Azure.Core/tests/Azure.Core.Tests.csproj  |   4 -
 8 files changed, 214 insertions(+), 13 deletions(-)
 create mode 100644 sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
 create mode 100644 sdk/core/Azure.Core/src/RehydrationToken.cs
 create mode 100644 sdk/core/Azure.Core/src/Shared/HeaderSource.cs

diff --git a/eng/Directory.Build.Common.targets b/eng/Directory.Build.Common.targets
index b487c45f0401..483c44700d8e 100644
--- a/eng/Directory.Build.Common.targets
+++ b/eng/Directory.Build.Common.targets
@@ -211,6 +211,7 @@
     <Compile Include="$(AzureCoreSharedSources)DiagnosticScopeFactory.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)FixedDelayWithNoJitterStrategy.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)FormUrlEncodedContent.cs" LinkBase="Shared/Core" />
+    <Compile Include="$(AzureCoreSharedSources)HeaderSource.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)HttpMessageSanitizer.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)HttpPipelineExtensions.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)IOperationSource.cs" LinkBase="Shared/Core" />
diff --git a/sdk/core/Azure.Core/src/Azure.Core.csproj b/sdk/core/Azure.Core/src/Azure.Core.csproj
index e16d7472d3b0..50f12e1bd222 100644
--- a/sdk/core/Azure.Core/src/Azure.Core.csproj
+++ b/sdk/core/Azure.Core/src/Azure.Core.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Description>This is the implementation of the Azure Client Pipeline</Description>
     <AssemblyTitle>Microsoft Azure Client Pipeline</AssemblyTitle>
@@ -21,6 +21,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" />
+    <PackageReference Include="System.ClientModel" />
     <PackageReference Include="System.Numerics.Vectors" />
     <PackageReference Include="System.Diagnostics.DiagnosticSource" />
     <PackageReference Include="System.Threading.Tasks.Extensions" />
@@ -48,6 +49,8 @@
     <Compile Include="Shared\AzureKeyCredentialPolicy.cs" />
     <Compile Include="Shared\AzureSasCredentialSynchronousPolicy.cs" />
     <Compile Include="Shared\Base64Url.cs" />
+    <Compile Include="Shared\ChangeTrackingList.cs" />
+    <Compile Include="Shared\ChangeTrackingDictionary.cs" />
     <Compile Include="Shared\ClientDiagnostics.cs" />
     <Compile Include="Shared\ContentTypeUtilities.cs" />
     <Compile Include="Shared\DiagnosticScope.cs" />
@@ -56,6 +59,7 @@
     <Compile Include="Shared\EventSourceEventFormatting.cs" />
     <Compile Include="Shared\FixedDelayWithNoJitterStrategy.cs" />
     <Compile Include="Shared\HashCodeBuilder.cs" />
+    <Compile Include="Shared\HeaderSource.cs" />
     <Compile Include="Shared\HttpMessageSanitizer.cs" />
     <Compile Include="Shared\InitializationConstructorAttribute.cs" />
     <Compile Include="Shared\Multipart\MemoryResponse.cs" />
@@ -63,6 +67,8 @@
     <Compile Include="Shared\OperationInternalBase.cs" />
     <Compile Include="Shared\TrimmingAttribute.cs" />
     <Compile Include="Shared\VoidValue.cs" />
+    <Compile Include="Shared\Optional.cs" />
+    <Compile Include="Shared\OperationFinalStateVia.cs" />
     <Compile Include="Shared\OperationInternal.cs" />
     <Compile Include="Shared\OperationInternalOfT.cs" />
     <Compile Include="Shared\SequentialDelayStrategy.cs" />
diff --git a/sdk/core/Azure.Core/src/Operation.cs b/sdk/core/Azure.Core/src/Operation.cs
index 0f12ae9f90ca..7ff18388e0f8 100644
--- a/sdk/core/Azure.Core/src/Operation.cs
+++ b/sdk/core/Azure.Core/src/Operation.cs
@@ -16,6 +16,11 @@ namespace Azure
     public abstract class Operation
 #pragma warning restore AZC0012 // Avoid single word type names
     {
+        /// <summary>
+        /// Get a token that can be used to rehydrate the operation.
+        /// </summary>
+        public virtual RehydrationToken? GetRehydrationToken() => null;
+
         /// <summary>
         /// Gets an ID representing the operation that can be used to poll for
         /// the status of the long-running operation.
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
new file mode 100644
index 000000000000..e9db5971c926
--- /dev/null
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -0,0 +1,135 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using System.ClientModel.Primitives;
+using System.Text.Json;
+
+#nullable disable
+
+namespace Azure.Core
+{
+    public partial struct RehydrationToken : IJsonModel<RehydrationToken>
+    {
+        internal RehydrationToken DeserializeRehydrationToken(JsonElement element, ModelReaderWriterOptions options)
+        {
+            if (element.ValueKind == JsonValueKind.Null)
+            {
+                return default;
+            }
+            Optional<Guid> id = default;
+            string version = string.Empty;
+            HeaderSource headerSource = default;
+            string nextRequestUri = string.Empty;
+            string initialUri = string.Empty;
+            RequestMethod requestMethod = default;
+            bool originalResponseHasLocation = default;
+            Optional<string> lastKnownLocation = default;
+            OperationFinalStateVia finalStateVia = default;
+
+            foreach (var property in element.EnumerateObject())
+            {
+                if (property.NameEquals("id"u8))
+                {
+                    if (property.Value.ValueKind == JsonValueKind.Null)
+                    {
+                        continue;
+                    }
+                    id = Guid.Parse(property.Value.GetString());
+                }
+                if (property.NameEquals("version"u8))
+                {
+                    version = property.Value.GetString();
+                    continue;
+                }
+                if (property.NameEquals("headerSource"u8))
+                {
+                    if (!Enum.TryParse(property.Value.GetString(), out headerSource))
+                    {
+                        headerSource = default;
+                    }
+                    continue;
+                }
+                if (property.NameEquals("nextRequestUri"u8))
+                {
+                    nextRequestUri = property.Value.GetString();
+                    continue;
+                }
+                if (property.NameEquals("initialUri"u8))
+                {
+                    initialUri = property.Value.GetString();
+                    continue;
+                }
+                if (property.NameEquals("requestMethod"u8))
+                {
+                    requestMethod = new RequestMethod(property.Value.GetString());
+                    continue;
+                }
+                if (property.NameEquals("originalResponseHasLocation"u8))
+                {
+                    originalResponseHasLocation = property.Value.GetBoolean();
+                    continue;
+                }
+                if (property.NameEquals("lastKnownLocation"u8))
+                {
+                    if (property.Value.ValueKind == JsonValueKind.Null)
+                    {
+                        continue;
+                    }
+                    lastKnownLocation = property.Value.GetString();
+                    continue;
+                }
+                if (property.NameEquals("finalStateVia"u8))
+                {
+                    if (!Enum.TryParse(property.Value.GetString(), out finalStateVia))
+                    {
+                        finalStateVia = default;
+                    }
+                    continue;
+                }
+            }
+            return new RehydrationToken(id.Value, version, headerSource, nextRequestUri, initialUri, requestMethod, originalResponseHasLocation, lastKnownLocation.Value, finalStateVia);
+        }
+
+        void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options)
+        {
+            writer.WriteStartObject();
+            writer.WritePropertyName("id"u8);
+            writer.WriteStringValue(Id.ToString());
+            writer.WritePropertyName("version"u8);
+            writer.WriteStringValue(Version);
+            writer.WritePropertyName("headerSource"u8);
+            writer.WriteStringValue(HeaderSource.ToString());
+            writer.WritePropertyName("nextRequestUri"u8);
+            writer.WriteStringValue(NextRequestUri);
+            writer.WritePropertyName("initialUri"u8);
+            writer.WriteStringValue(InitialUri);
+            writer.WritePropertyName("requestMethod"u8);
+            writer.WriteStringValue(RequestMethod.ToString());
+            writer.WritePropertyName("originalResponseHasLocation"u8);
+            writer.WriteBooleanValue(OriginalResponseHasLocation);
+            writer.WritePropertyName("lastKnownLocation"u8);
+            writer.WriteStringValue(LastKnownLocation);
+            writer.WritePropertyName("finalStateVia"u8);
+            writer.WriteStringValue(FinalStateVia.ToString());
+            writer.WriteEndObject();
+        }
+
+        RehydrationToken IJsonModel<RehydrationToken>.Create(ref Utf8JsonReader reader, ModelReaderWriterOptions options)
+        {
+            using var document = JsonDocument.ParseValue(ref reader);
+            return DeserializeRehydrationToken(document.RootElement, options);
+        }
+
+        BinaryData IPersistableModel<RehydrationToken>.Write(ModelReaderWriterOptions options)
+            => ModelReaderWriter.Write(this, options);
+
+        RehydrationToken IPersistableModel<RehydrationToken>.Create(BinaryData data, ModelReaderWriterOptions options)
+        {
+            using var document = JsonDocument.Parse(data);
+            return DeserializeRehydrationToken(document.RootElement, options);
+        }
+
+        string IPersistableModel<RehydrationToken>.GetFormatFromOptions(ModelReaderWriterOptions options) => "J";
+    }
+}
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
new file mode 100644
index 000000000000..1cb3975260d8
--- /dev/null
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -0,0 +1,53 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+#nullable enable
+
+using System;
+
+namespace Azure.Core
+{
+    /// <summary>
+    /// Represents a token that can be used to rehydrate a long-running operation.
+    /// </summary>
+    public partial struct RehydrationToken
+    {
+        /// <summary>
+        /// Gets an ID representing the operation that can be used to poll for
+        /// the status of the long-running operation.
+        /// </summary>
+        public Guid? Id { get; }
+
+        internal string Version { get; } = "1.0.0";
+
+        internal HeaderSource HeaderSource { get; }
+
+        internal string NextRequestUri { get; }
+
+        internal string InitialUri { get; }
+
+        internal RequestMethod RequestMethod { get; }
+
+        internal bool OriginalResponseHasLocation { get; }
+
+        internal string? LastKnownLocation { get; }
+
+        internal OperationFinalStateVia FinalStateVia { get; }
+
+        internal RehydrationToken(Guid? id, string? version, HeaderSource headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, bool originalResponseHasLocation, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
+        {
+            Id = id;
+            if (version is not null)
+            {
+                Version = version;
+            }
+            HeaderSource = headerSource;
+            NextRequestUri = nextRequestUri;
+            InitialUri = initialUri;
+            RequestMethod = requestMethod;
+            OriginalResponseHasLocation = originalResponseHasLocation;
+            LastKnownLocation = lastKnownLocation;
+            FinalStateVia = finalStateVia;
+        }
+    }
+}
diff --git a/sdk/core/Azure.Core/src/Shared/HeaderSource.cs b/sdk/core/Azure.Core/src/Shared/HeaderSource.cs
new file mode 100644
index 000000000000..a0be39f96246
--- /dev/null
+++ b/sdk/core/Azure.Core/src/Shared/HeaderSource.cs
@@ -0,0 +1,13 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+namespace Azure.Core
+{
+    internal enum HeaderSource
+    {
+        None,
+        OperationLocation,
+        AzureAsyncOperation,
+        Location
+    }
+}
diff --git a/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs b/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
index 120c2d63a7d3..3f38b46aba34 100644
--- a/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
+++ b/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
@@ -394,14 +394,6 @@ private static HeaderSource GetHeaderSource(RequestMethod requestMethod, Uri req
             return HeaderSource.None;
         }
 
-        private enum HeaderSource
-        {
-            None,
-            OperationLocation,
-            AzureAsyncOperation,
-            Location
-        }
-
         private class CompletedOperation : IOperation
         {
             private readonly OperationState _operationState;
diff --git a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
index 0faa6ea6ffe1..fbcc25e1998f 100644
--- a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
+++ b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
@@ -30,8 +30,6 @@
     <Compile Remove="..\src\Shared\Multipart\MemoryResponse.cs" />
     <Compile Include="..\src\Shared\ArrayBufferWriter.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\AzureResourceProviderNamespaceAttribute.cs" LinkBase="Shared" />
-    <Compile Include="..\src\Shared\ChangeTrackingDictionary.cs" LinkBase="Shared" />
-    <Compile Include="..\src\Shared\ChangeTrackingList.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\ConnectionString.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\FormUrlEncodedContent.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\ForwardsClientCallsAttribute.cs" LinkBase="Shared" />
@@ -44,8 +42,6 @@
     <Compile Include="..\src\Shared\NextLinkOperationImplementation.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoBodyResponseOfT.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoValueResponseOfT.cs" LinkBase="Shared" />
-    <Compile Include="..\src\Shared\OperationFinalStateVia.cs" LinkBase="Shared" />
-    <Compile Include="..\src\Shared\Optional.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\Page.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\PageableHelpers.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\PageResponseEnumerator.cs" LinkBase="Shared" />

From b425271c29124f6cbea8bd9e4b89105aa784edb4 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 26 Jan 2024 13:56:06 +0800
Subject: [PATCH 02/16] export API

---
 sdk/core/Azure.Core/api/Azure.Core.net461.cs        | 13 +++++++++++++
 sdk/core/Azure.Core/api/Azure.Core.net472.cs        | 13 +++++++++++++
 sdk/core/Azure.Core/api/Azure.Core.net6.0.cs        | 13 +++++++++++++
 .../Azure.Core/api/Azure.Core.netstandard2.0.cs     | 13 +++++++++++++
 4 files changed, 52 insertions(+)

diff --git a/sdk/core/Azure.Core/api/Azure.Core.net461.cs b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
index 49995b0e56e3..614cf4fa5bee 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net461.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
@@ -137,6 +137,7 @@ protected Operation() { }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override int GetHashCode() { throw null; }
         public abstract Azure.Response GetRawResponse();
+        public virtual Azure.Core.RehydrationToken? GetRehydrationToken() { throw null; }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override string? ToString() { throw null; }
         public abstract Azure.Response UpdateStatus(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -518,6 +519,18 @@ public static partial class MultipartResponse
         public static Azure.Response[] Parse(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
+    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
+    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    {
+        private object _dummy;
+        private int _dummyPrimitive;
+        public System.Guid? Id { get { throw null; } }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+    }
     public abstract partial class Request : System.IDisposable
     {
         protected Request() { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net472.cs b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
index 49995b0e56e3..614cf4fa5bee 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net472.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
@@ -137,6 +137,7 @@ protected Operation() { }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override int GetHashCode() { throw null; }
         public abstract Azure.Response GetRawResponse();
+        public virtual Azure.Core.RehydrationToken? GetRehydrationToken() { throw null; }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override string? ToString() { throw null; }
         public abstract Azure.Response UpdateStatus(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -518,6 +519,18 @@ public static partial class MultipartResponse
         public static Azure.Response[] Parse(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
+    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
+    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    {
+        private object _dummy;
+        private int _dummyPrimitive;
+        public System.Guid? Id { get { throw null; } }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+    }
     public abstract partial class Request : System.IDisposable
     {
         protected Request() { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
index 16d3e7cb99ce..3fbb3dcbb17c 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
@@ -137,6 +137,7 @@ protected Operation() { }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override int GetHashCode() { throw null; }
         public abstract Azure.Response GetRawResponse();
+        public virtual Azure.Core.RehydrationToken? GetRehydrationToken() { throw null; }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override string? ToString() { throw null; }
         public abstract Azure.Response UpdateStatus(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -518,6 +519,18 @@ public static partial class MultipartResponse
         public static Azure.Response[] Parse(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
+    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
+    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    {
+        private object _dummy;
+        private int _dummyPrimitive;
+        public System.Guid? Id { get { throw null; } }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+    }
     public abstract partial class Request : System.IDisposable
     {
         protected Request() { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
index 49995b0e56e3..614cf4fa5bee 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
@@ -137,6 +137,7 @@ protected Operation() { }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override int GetHashCode() { throw null; }
         public abstract Azure.Response GetRawResponse();
+        public virtual Azure.Core.RehydrationToken? GetRehydrationToken() { throw null; }
         [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
         public override string? ToString() { throw null; }
         public abstract Azure.Response UpdateStatus(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken));
@@ -518,6 +519,18 @@ public static partial class MultipartResponse
         public static Azure.Response[] Parse(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
+    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
+    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    {
+        private object _dummy;
+        private int _dummyPrimitive;
+        public System.Guid? Id { get { throw null; } }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+    }
     public abstract partial class Request : System.IDisposable
     {
         protected Request() { }

From 74183b13970d7091300a8124855e66d724bfe256 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 26 Jan 2024 15:00:12 +0800
Subject: [PATCH 03/16] make struct readonly

---
 sdk/core/Azure.Core/src/RehydrationToken.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index 1cb3975260d8..a0ed1d148bfc 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -10,7 +10,7 @@ namespace Azure.Core
     /// <summary>
     /// Represents a token that can be used to rehydrate a long-running operation.
     /// </summary>
-    public partial struct RehydrationToken
+    public readonly partial struct RehydrationToken
     {
         /// <summary>
         /// Gets an ID representing the operation that can be used to poll for

From 1530b50ac9e2dcee80ad02f4f37b0b530382c16a Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 26 Jan 2024 15:01:03 +0800
Subject: [PATCH 04/16] export API

---
 sdk/core/Azure.Core/api/Azure.Core.net461.cs         | 6 +++---
 sdk/core/Azure.Core/api/Azure.Core.net472.cs         | 6 +++---
 sdk/core/Azure.Core/api/Azure.Core.net6.0.cs         | 6 +++---
 sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs | 6 +++---
 4 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/sdk/core/Azure.Core/api/Azure.Core.net461.cs b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
index 614cf4fa5bee..3cdc6d4c25a0 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net461.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
@@ -520,10 +520,10 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
     {
-        private object _dummy;
-        private int _dummyPrimitive;
+        private readonly object _dummy;
+        private readonly int _dummyPrimitive;
         public System.Guid? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net472.cs b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
index 614cf4fa5bee..3cdc6d4c25a0 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net472.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
@@ -520,10 +520,10 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
     {
-        private object _dummy;
-        private int _dummyPrimitive;
+        private readonly object _dummy;
+        private readonly int _dummyPrimitive;
         public System.Guid? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
index 3fbb3dcbb17c..6772bc9c0a60 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
@@ -520,10 +520,10 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
     {
-        private object _dummy;
-        private int _dummyPrimitive;
+        private readonly object _dummy;
+        private readonly int _dummyPrimitive;
         public System.Guid? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
index 614cf4fa5bee..3cdc6d4c25a0 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
@@ -520,10 +520,10 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
     {
-        private object _dummy;
-        private int _dummyPrimitive;
+        private readonly object _dummy;
+        private readonly int _dummyPrimitive;
         public System.Guid? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }

From ddc3f57da8f48298d1cd1a877eaa631a037c874e Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Tue, 30 Jan 2024 10:39:31 +0800
Subject: [PATCH 05/16] update

---
 eng/Directory.Build.Common.targets                        | 1 -
 sdk/core/Azure.Core/src/Azure.Core.csproj                 | 1 -
 sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs | 7 ++-----
 sdk/core/Azure.Core/src/RehydrationToken.cs               | 4 ++--
 .../src/Shared/NextLinkOperationImplementation.cs         | 8 ++++++++
 5 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/eng/Directory.Build.Common.targets b/eng/Directory.Build.Common.targets
index 483c44700d8e..b487c45f0401 100644
--- a/eng/Directory.Build.Common.targets
+++ b/eng/Directory.Build.Common.targets
@@ -211,7 +211,6 @@
     <Compile Include="$(AzureCoreSharedSources)DiagnosticScopeFactory.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)FixedDelayWithNoJitterStrategy.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)FormUrlEncodedContent.cs" LinkBase="Shared/Core" />
-    <Compile Include="$(AzureCoreSharedSources)HeaderSource.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)HttpMessageSanitizer.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)HttpPipelineExtensions.cs" LinkBase="Shared/Core" />
     <Compile Include="$(AzureCoreSharedSources)IOperationSource.cs" LinkBase="Shared/Core" />
diff --git a/sdk/core/Azure.Core/src/Azure.Core.csproj b/sdk/core/Azure.Core/src/Azure.Core.csproj
index 50f12e1bd222..29e35e0c3218 100644
--- a/sdk/core/Azure.Core/src/Azure.Core.csproj
+++ b/sdk/core/Azure.Core/src/Azure.Core.csproj
@@ -59,7 +59,6 @@
     <Compile Include="Shared\EventSourceEventFormatting.cs" />
     <Compile Include="Shared\FixedDelayWithNoJitterStrategy.cs" />
     <Compile Include="Shared\HashCodeBuilder.cs" />
-    <Compile Include="Shared\HeaderSource.cs" />
     <Compile Include="Shared\HttpMessageSanitizer.cs" />
     <Compile Include="Shared\InitializationConstructorAttribute.cs" />
     <Compile Include="Shared\Multipart\MemoryResponse.cs" />
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index e9db5971c926..bf6b9a39821c 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -19,7 +19,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
             }
             Optional<Guid> id = default;
             string version = string.Empty;
-            HeaderSource headerSource = default;
+            string headerSource = default;
             string nextRequestUri = string.Empty;
             string initialUri = string.Empty;
             RequestMethod requestMethod = default;
@@ -44,10 +44,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                 }
                 if (property.NameEquals("headerSource"u8))
                 {
-                    if (!Enum.TryParse(property.Value.GetString(), out headerSource))
-                    {
-                        headerSource = default;
-                    }
+                    headerSource = property.Value.GetString();
                     continue;
                 }
                 if (property.NameEquals("nextRequestUri"u8))
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index a0ed1d148bfc..16c891e105f3 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -20,7 +20,7 @@ public readonly partial struct RehydrationToken
 
         internal string Version { get; } = "1.0.0";
 
-        internal HeaderSource HeaderSource { get; }
+        internal string HeaderSource { get; }
 
         internal string NextRequestUri { get; }
 
@@ -34,7 +34,7 @@ public readonly partial struct RehydrationToken
 
         internal OperationFinalStateVia FinalStateVia { get; }
 
-        internal RehydrationToken(Guid? id, string? version, HeaderSource headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, bool originalResponseHasLocation, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
+        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, bool originalResponseHasLocation, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
         {
             Id = id;
             if (version is not null)
diff --git a/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs b/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
index 3f38b46aba34..120c2d63a7d3 100644
--- a/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
+++ b/sdk/core/Azure.Core/src/Shared/NextLinkOperationImplementation.cs
@@ -394,6 +394,14 @@ private static HeaderSource GetHeaderSource(RequestMethod requestMethod, Uri req
             return HeaderSource.None;
         }
 
+        private enum HeaderSource
+        {
+            None,
+            OperationLocation,
+            AzureAsyncOperation,
+            Location
+        }
+
         private class CompletedOperation : IOperation
         {
             private readonly OperationState _operationState;

From c40f52a9ddbde7d6d43c9d5bc0c01efc70dd4411 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Tue, 30 Jan 2024 17:18:14 +0800
Subject: [PATCH 06/16] clean up

---
 sdk/core/Azure.Core/src/Shared/HeaderSource.cs | 13 -------------
 1 file changed, 13 deletions(-)
 delete mode 100644 sdk/core/Azure.Core/src/Shared/HeaderSource.cs

diff --git a/sdk/core/Azure.Core/src/Shared/HeaderSource.cs b/sdk/core/Azure.Core/src/Shared/HeaderSource.cs
deleted file mode 100644
index a0be39f96246..000000000000
--- a/sdk/core/Azure.Core/src/Shared/HeaderSource.cs
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
-// Licensed under the MIT License.
-
-namespace Azure.Core
-{
-    internal enum HeaderSource
-    {
-        None,
-        OperationLocation,
-        AzureAsyncOperation,
-        Location
-    }
-}

From 087a93976186ba85dc4dcf61d101380d47d586a3 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Wed, 31 Jan 2024 10:49:50 +0800
Subject: [PATCH 07/16] update

---
 .../Azure.Core/src/RehydrationToken.Serialization.cs   | 10 +---------
 sdk/core/Azure.Core/src/RehydrationToken.cs            |  5 +----
 2 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index bf6b9a39821c..eff6721beb79 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -23,7 +23,6 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
             string nextRequestUri = string.Empty;
             string initialUri = string.Empty;
             RequestMethod requestMethod = default;
-            bool originalResponseHasLocation = default;
             Optional<string> lastKnownLocation = default;
             OperationFinalStateVia finalStateVia = default;
 
@@ -62,11 +61,6 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     requestMethod = new RequestMethod(property.Value.GetString());
                     continue;
                 }
-                if (property.NameEquals("originalResponseHasLocation"u8))
-                {
-                    originalResponseHasLocation = property.Value.GetBoolean();
-                    continue;
-                }
                 if (property.NameEquals("lastKnownLocation"u8))
                 {
                     if (property.Value.ValueKind == JsonValueKind.Null)
@@ -85,7 +79,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     continue;
                 }
             }
-            return new RehydrationToken(id.Value, version, headerSource, nextRequestUri, initialUri, requestMethod, originalResponseHasLocation, lastKnownLocation.Value, finalStateVia);
+            return new RehydrationToken(id.Value, version, headerSource, nextRequestUri, initialUri, requestMethod, lastKnownLocation.Value, finalStateVia);
         }
 
         void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options)
@@ -103,8 +97,6 @@ void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriter
             writer.WriteStringValue(InitialUri);
             writer.WritePropertyName("requestMethod"u8);
             writer.WriteStringValue(RequestMethod.ToString());
-            writer.WritePropertyName("originalResponseHasLocation"u8);
-            writer.WriteBooleanValue(OriginalResponseHasLocation);
             writer.WritePropertyName("lastKnownLocation"u8);
             writer.WriteStringValue(LastKnownLocation);
             writer.WritePropertyName("finalStateVia"u8);
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index 16c891e105f3..e57c6ddb4236 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -28,13 +28,11 @@ public readonly partial struct RehydrationToken
 
         internal RequestMethod RequestMethod { get; }
 
-        internal bool OriginalResponseHasLocation { get; }
-
         internal string? LastKnownLocation { get; }
 
         internal OperationFinalStateVia FinalStateVia { get; }
 
-        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, bool originalResponseHasLocation, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
+        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
         {
             Id = id;
             if (version is not null)
@@ -45,7 +43,6 @@ internal RehydrationToken(Guid? id, string? version, string headerSource, string
             NextRequestUri = nextRequestUri;
             InitialUri = initialUri;
             RequestMethod = requestMethod;
-            OriginalResponseHasLocation = originalResponseHasLocation;
             LastKnownLocation = lastKnownLocation;
             FinalStateVia = finalStateVia;
         }

From 4c5f363cb4fc5001959b47e26bc3d6d11f903e3a Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Thu, 1 Feb 2024 09:02:54 +0800
Subject: [PATCH 08/16] remove Optional

---
 sdk/core/Azure.Core/src/Azure.Core.csproj     |  3 ---
 .../src/RehydrationToken.Serialization.cs     | 22 +++++++++----------
 .../Azure.Core/tests/Azure.Core.Tests.csproj  |  3 +++
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/sdk/core/Azure.Core/src/Azure.Core.csproj b/sdk/core/Azure.Core/src/Azure.Core.csproj
index 29e35e0c3218..20088b485b0d 100644
--- a/sdk/core/Azure.Core/src/Azure.Core.csproj
+++ b/sdk/core/Azure.Core/src/Azure.Core.csproj
@@ -49,8 +49,6 @@
     <Compile Include="Shared\AzureKeyCredentialPolicy.cs" />
     <Compile Include="Shared\AzureSasCredentialSynchronousPolicy.cs" />
     <Compile Include="Shared\Base64Url.cs" />
-    <Compile Include="Shared\ChangeTrackingList.cs" />
-    <Compile Include="Shared\ChangeTrackingDictionary.cs" />
     <Compile Include="Shared\ClientDiagnostics.cs" />
     <Compile Include="Shared\ContentTypeUtilities.cs" />
     <Compile Include="Shared\DiagnosticScope.cs" />
@@ -66,7 +64,6 @@
     <Compile Include="Shared\OperationInternalBase.cs" />
     <Compile Include="Shared\TrimmingAttribute.cs" />
     <Compile Include="Shared\VoidValue.cs" />
-    <Compile Include="Shared\Optional.cs" />
     <Compile Include="Shared\OperationFinalStateVia.cs" />
     <Compile Include="Shared\OperationInternal.cs" />
     <Compile Include="Shared\OperationInternalOfT.cs" />
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index eff6721beb79..c191f8017ea4 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -5,7 +5,7 @@
 using System.ClientModel.Primitives;
 using System.Text.Json;
 
-#nullable disable
+#nullable enable
 
 namespace Azure.Core
 {
@@ -17,13 +17,13 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
             {
                 return default;
             }
-            Optional<Guid> id = default;
+            Guid? id = default;
             string version = string.Empty;
-            string headerSource = default;
+            string headerSource = string.Empty;
             string nextRequestUri = string.Empty;
             string initialUri = string.Empty;
             RequestMethod requestMethod = default;
-            Optional<string> lastKnownLocation = default;
+            string? lastKnownLocation = null;
             OperationFinalStateVia finalStateVia = default;
 
             foreach (var property in element.EnumerateObject())
@@ -34,31 +34,31 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     {
                         continue;
                     }
-                    id = Guid.Parse(property.Value.GetString());
+                    id = Guid.Parse(property.Value.GetString()!);
                 }
                 if (property.NameEquals("version"u8))
                 {
-                    version = property.Value.GetString();
+                    version = property.Value.GetString()!;
                     continue;
                 }
                 if (property.NameEquals("headerSource"u8))
                 {
-                    headerSource = property.Value.GetString();
+                    headerSource = property.Value.GetString()!;
                     continue;
                 }
                 if (property.NameEquals("nextRequestUri"u8))
                 {
-                    nextRequestUri = property.Value.GetString();
+                    nextRequestUri = property.Value.GetString()!;
                     continue;
                 }
                 if (property.NameEquals("initialUri"u8))
                 {
-                    initialUri = property.Value.GetString();
+                    initialUri = property.Value.GetString()!;
                     continue;
                 }
                 if (property.NameEquals("requestMethod"u8))
                 {
-                    requestMethod = new RequestMethod(property.Value.GetString());
+                    requestMethod = new RequestMethod(property.Value.GetString()!);
                     continue;
                 }
                 if (property.NameEquals("lastKnownLocation"u8))
@@ -79,7 +79,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     continue;
                 }
             }
-            return new RehydrationToken(id.Value, version, headerSource, nextRequestUri, initialUri, requestMethod, lastKnownLocation.Value, finalStateVia);
+            return new RehydrationToken(id, version, headerSource, nextRequestUri, initialUri, requestMethod, lastKnownLocation, finalStateVia);
         }
 
         void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options)
diff --git a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
index fbcc25e1998f..78b946cbbc93 100644
--- a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
+++ b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
@@ -30,6 +30,8 @@
     <Compile Remove="..\src\Shared\Multipart\MemoryResponse.cs" />
     <Compile Include="..\src\Shared\ArrayBufferWriter.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\AzureResourceProviderNamespaceAttribute.cs" LinkBase="Shared" />
+    <Compile Include="..\src\Shared\ChangeTrackingDictionary.cs" LinkBase="Shared" />
+    <Compile Include="..\src\Shared\ChangeTrackingList.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\ConnectionString.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\FormUrlEncodedContent.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\ForwardsClientCallsAttribute.cs" LinkBase="Shared" />
@@ -42,6 +44,7 @@
     <Compile Include="..\src\Shared\NextLinkOperationImplementation.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoBodyResponseOfT.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoValueResponseOfT.cs" LinkBase="Shared" />
+    <Compile Include="..\src\Shared\Optional.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\Page.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\PageableHelpers.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\PageResponseEnumerator.cs" LinkBase="Shared" />

From 09e4e8e560149cc1ddd49e4482512d11526befe6 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Thu, 1 Feb 2024 23:38:36 +0800
Subject: [PATCH 09/16] update

---
 sdk/core/Azure.Core/src/Azure.Core.csproj                 | 1 -
 sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs | 7 ++-----
 sdk/core/Azure.Core/src/RehydrationToken.cs               | 4 ++--
 sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj         | 1 +
 4 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/sdk/core/Azure.Core/src/Azure.Core.csproj b/sdk/core/Azure.Core/src/Azure.Core.csproj
index 20088b485b0d..2dbf8c1dbc4b 100644
--- a/sdk/core/Azure.Core/src/Azure.Core.csproj
+++ b/sdk/core/Azure.Core/src/Azure.Core.csproj
@@ -64,7 +64,6 @@
     <Compile Include="Shared\OperationInternalBase.cs" />
     <Compile Include="Shared\TrimmingAttribute.cs" />
     <Compile Include="Shared\VoidValue.cs" />
-    <Compile Include="Shared\OperationFinalStateVia.cs" />
     <Compile Include="Shared\OperationInternal.cs" />
     <Compile Include="Shared\OperationInternalOfT.cs" />
     <Compile Include="Shared\SequentialDelayStrategy.cs" />
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index c191f8017ea4..b5955565162d 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -24,7 +24,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
             string initialUri = string.Empty;
             RequestMethod requestMethod = default;
             string? lastKnownLocation = null;
-            OperationFinalStateVia finalStateVia = default;
+            string finalStateVia = string.Empty;
 
             foreach (var property in element.EnumerateObject())
             {
@@ -72,10 +72,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                 }
                 if (property.NameEquals("finalStateVia"u8))
                 {
-                    if (!Enum.TryParse(property.Value.GetString(), out finalStateVia))
-                    {
-                        finalStateVia = default;
-                    }
+                    finalStateVia = property.Value.GetString()!;
                     continue;
                 }
             }
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index e57c6ddb4236..d5a7c5f876a0 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -30,9 +30,9 @@ public readonly partial struct RehydrationToken
 
         internal string? LastKnownLocation { get; }
 
-        internal OperationFinalStateVia FinalStateVia { get; }
+        internal string FinalStateVia { get; }
 
-        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, OperationFinalStateVia finalStateVia)
+        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, string finalStateVia)
         {
             Id = id;
             if (version is not null)
diff --git a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
index 78b946cbbc93..0faa6ea6ffe1 100644
--- a/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
+++ b/sdk/core/Azure.Core/tests/Azure.Core.Tests.csproj
@@ -44,6 +44,7 @@
     <Compile Include="..\src\Shared\NextLinkOperationImplementation.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoBodyResponseOfT.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\NoValueResponseOfT.cs" LinkBase="Shared" />
+    <Compile Include="..\src\Shared\OperationFinalStateVia.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\Optional.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\Page.cs" LinkBase="Shared" />
     <Compile Include="..\src\Shared\PageableHelpers.cs" LinkBase="Shared" />

From 282625608cbb10ca4b64257a76aec59ffb75053e Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 2 Feb 2024 08:30:32 +0800
Subject: [PATCH 10/16] Address comments

---
 sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs | 6 +++---
 sdk/core/Azure.Core/src/RehydrationToken.cs               | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index b5955565162d..70079d6c83b0 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -17,7 +17,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
             {
                 return default;
             }
-            Guid? id = default;
+            string? id = null;
             string version = string.Empty;
             string headerSource = string.Empty;
             string nextRequestUri = string.Empty;
@@ -34,7 +34,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     {
                         continue;
                     }
-                    id = Guid.Parse(property.Value.GetString()!);
+                    id = property.Value.GetString()!;
                 }
                 if (property.NameEquals("version"u8))
                 {
@@ -83,7 +83,7 @@ void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriter
         {
             writer.WriteStartObject();
             writer.WritePropertyName("id"u8);
-            writer.WriteStringValue(Id.ToString());
+            writer.WriteStringValue(Id);
             writer.WritePropertyName("version"u8);
             writer.WriteStringValue(Version);
             writer.WritePropertyName("headerSource"u8);
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index d5a7c5f876a0..4b9b6bab63ea 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -16,7 +16,7 @@ public readonly partial struct RehydrationToken
         /// Gets an ID representing the operation that can be used to poll for
         /// the status of the long-running operation.
         /// </summary>
-        public Guid? Id { get; }
+        public string? Id { get; }
 
         internal string Version { get; } = "1.0.0";
 
@@ -32,7 +32,7 @@ public readonly partial struct RehydrationToken
 
         internal string FinalStateVia { get; }
 
-        internal RehydrationToken(Guid? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, string finalStateVia)
+        internal RehydrationToken(string? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, string finalStateVia)
         {
             Id = id;
             if (version is not null)

From 4826528868a9504117bc13281e074eeb7b8a61f3 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Fri, 2 Feb 2024 08:32:50 +0800
Subject: [PATCH 11/16] update API

---
 sdk/core/Azure.Core/api/Azure.Core.net461.cs         | 2 +-
 sdk/core/Azure.Core/api/Azure.Core.net472.cs         | 2 +-
 sdk/core/Azure.Core/api/Azure.Core.net6.0.cs         | 2 +-
 sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/sdk/core/Azure.Core/api/Azure.Core.net461.cs b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
index 3cdc6d4c25a0..c51499d7d22e 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net461.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
@@ -524,7 +524,7 @@ public static partial class MultipartResponse
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
-        public System.Guid? Id { get { throw null; } }
+        public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net472.cs b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
index 3cdc6d4c25a0..c51499d7d22e 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net472.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
@@ -524,7 +524,7 @@ public static partial class MultipartResponse
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
-        public System.Guid? Id { get { throw null; } }
+        public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
index 6772bc9c0a60..e5ae8ee52ec7 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
@@ -524,7 +524,7 @@ public static partial class MultipartResponse
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
-        public System.Guid? Id { get { throw null; } }
+        public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
diff --git a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
index 3cdc6d4c25a0..c51499d7d22e 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
@@ -524,7 +524,7 @@ public static partial class MultipartResponse
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
-        public System.Guid? Id { get { throw null; } }
+        public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }

From 5992a975086b50167d3913e513976669112f29f8 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Tue, 6 Feb 2024 14:00:48 +0800
Subject: [PATCH 12/16] Address PR comments.

---
 sdk/core/Azure.Core/CHANGELOG.md                    |  2 ++
 .../src/RehydrationToken.Serialization.cs           | 13 +++++++++----
 sdk/core/Azure.Core/src/RehydrationToken.cs         |  4 ----
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/sdk/core/Azure.Core/CHANGELOG.md b/sdk/core/Azure.Core/CHANGELOG.md
index f8f75384227c..1fbb14c810c1 100644
--- a/sdk/core/Azure.Core/CHANGELOG.md
+++ b/sdk/core/Azure.Core/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 ### Features Added
 
+- Add `GetRehydrationToken` to `Operation` for rehydration purpose.
+
 ### Breaking Changes
 
 ### Bugs Fixed
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index 70079d6c83b0..d6a7198a4988 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -5,18 +5,23 @@
 using System.ClientModel.Primitives;
 using System.Text.Json;
 
-#nullable enable
-
 namespace Azure.Core
 {
     public partial struct RehydrationToken : IJsonModel<RehydrationToken>
     {
         internal RehydrationToken DeserializeRehydrationToken(JsonElement element, ModelReaderWriterOptions options)
         {
+            var format = options.Format == "W" ? ((IPersistableModel<RehydrationToken>)this).GetFormatFromOptions(options) : options.Format;
+            if (format != "J")
+            {
+                throw new FormatException($"The model {nameof(RehydrationToken)} does not support '{format}' format.");
+            }
+
             if (element.ValueKind == JsonValueKind.Null)
             {
-                return default;
+                throw new InvalidOperationException("Cannot deserialize a null value to a non-nullable RehydrationToken");
             }
+
             string? id = null;
             string version = string.Empty;
             string headerSource = string.Empty;
@@ -34,7 +39,7 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                     {
                         continue;
                     }
-                    id = property.Value.GetString()!;
+                    id = property.Value.GetString();
                 }
                 if (property.NameEquals("version"u8))
                 {
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index 4b9b6bab63ea..0d3cd4f0f63b 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -1,10 +1,6 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-#nullable enable
-
-using System;
-
 namespace Azure.Core
 {
     /// <summary>

From 3b04c8547bc16ee3e5382485b941d3006c955fb2 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Wed, 7 Feb 2024 10:36:05 +0800
Subject: [PATCH 13/16] Address comments

---
 .../src/RehydrationToken.Serialization.cs     | 25 ++++++++++++++-----
 sdk/core/Azure.Core/src/RehydrationToken.cs   |  8 ++++++
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index d6a7198a4988..af2efbb45075 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.ClientModel.Primitives;
+using System.Diagnostics;
 using System.Text.Json;
 
 namespace Azure.Core
@@ -43,27 +44,37 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                 }
                 if (property.NameEquals("version"u8))
                 {
-                    version = property.Value.GetString()!;
+                    var versionString = property.Value.GetString();
+                    Debug.Assert(versionString is not null);
+                    version = versionString!;
                     continue;
                 }
                 if (property.NameEquals("headerSource"u8))
                 {
-                    headerSource = property.Value.GetString()!;
+                    var headerSourceString = property.Value.GetString();
+                    Debug.Assert(headerSourceString is not null);
+                    headerSource = headerSourceString!;
                     continue;
                 }
                 if (property.NameEquals("nextRequestUri"u8))
                 {
-                    nextRequestUri = property.Value.GetString()!;
+                    var nextRequestUriString = property.Value.GetString();
+                    Debug.Assert(nextRequestUriString is not null);
+                    nextRequestUri = nextRequestUriString!;
                     continue;
                 }
                 if (property.NameEquals("initialUri"u8))
                 {
-                    initialUri = property.Value.GetString()!;
+                    var initialUriString = property.Value.GetString();
+                    Debug.Assert(initialUriString is not null);
+                    initialUri = initialUriString!;
                     continue;
                 }
                 if (property.NameEquals("requestMethod"u8))
                 {
-                    requestMethod = new RequestMethod(property.Value.GetString()!);
+                    var requestMethodString = property.Value.GetString();
+                    Debug.Assert(requestMethodString is not null);
+                    requestMethod = new RequestMethod(requestMethodString!);
                     continue;
                 }
                 if (property.NameEquals("lastKnownLocation"u8))
@@ -77,7 +88,9 @@ internal RehydrationToken DeserializeRehydrationToken(JsonElement element, Model
                 }
                 if (property.NameEquals("finalStateVia"u8))
                 {
-                    finalStateVia = property.Value.GetString()!;
+                    var finalStateViaString = property.Value.GetString();
+                    Debug.Assert(finalStateViaString is not null);
+                    finalStateVia = finalStateViaString!;
                     continue;
                 }
             }
diff --git a/sdk/core/Azure.Core/src/RehydrationToken.cs b/sdk/core/Azure.Core/src/RehydrationToken.cs
index 0d3cd4f0f63b..13addaadc64f 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.cs
@@ -14,18 +14,26 @@ public readonly partial struct RehydrationToken
         /// </summary>
         public string? Id { get; }
 
+        // Version for this contract itself since we might change the members in the future.
         internal string Version { get; } = "1.0.0";
 
+        // The below members are used to re-construct <cref="NextLinkOperationImplemenation">.
+        // Value of <cref="NextLinkOperationImplemenration.HeaderSrouce">.
         internal string HeaderSource { get; }
 
+        // The polling Uri of the operation.
         internal string NextRequestUri { get; }
 
+        // The initial Uri of the operation.
         internal string InitialUri { get; }
 
+        // The Http request method of the operation.
         internal RequestMethod RequestMethod { get; }
 
+        // The last known location of the operation.
         internal string? LastKnownLocation { get; }
 
+        // The final state of the operation, could be azure-async-operation, location, original-uri or operation-location.
         internal string FinalStateVia { get; }
 
         internal RehydrationToken(string? id, string? version, string headerSource, string nextRequestUri, string initialUri, RequestMethod requestMethod, string? lastKnownLocation, string finalStateVia)

From 168ae3f539db7f1f05948ac57b95313f8b4b2277 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Thu, 8 Feb 2024 15:43:50 +0800
Subject: [PATCH 14/16] Add unit tests

---
 .../src/RehydrationToken.Serialization.cs     | 50 +++++++++++++++++--
 .../Azure.Core/tests/RehydrationTokenTests.cs | 34 +++++++++++++
 2 files changed, 79 insertions(+), 5 deletions(-)
 create mode 100644 sdk/core/Azure.Core/tests/RehydrationTokenTests.cs

diff --git a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
index af2efbb45075..470323817458 100644
--- a/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
+++ b/sdk/core/Azure.Core/src/RehydrationToken.Serialization.cs
@@ -8,7 +8,7 @@
 
 namespace Azure.Core
 {
-    public partial struct RehydrationToken : IJsonModel<RehydrationToken>
+    public partial struct RehydrationToken : IJsonModel<RehydrationToken>, IJsonModel<object>
     {
         internal RehydrationToken DeserializeRehydrationToken(JsonElement element, ModelReaderWriterOptions options)
         {
@@ -121,19 +121,59 @@ void IJsonModel<RehydrationToken>.Write(Utf8JsonWriter writer, ModelReaderWriter
 
         RehydrationToken IJsonModel<RehydrationToken>.Create(ref Utf8JsonReader reader, ModelReaderWriterOptions options)
         {
-            using var document = JsonDocument.ParseValue(ref reader);
+            var format = options.Format == "W" ? ((IPersistableModel<RehydrationToken>)this).GetFormatFromOptions(options) : options.Format;
+            if (format != "J")
+            {
+                throw new FormatException($"The model {nameof(RehydrationToken)} does not support '{format}' format.");
+            }
+
+            using JsonDocument document = JsonDocument.ParseValue(ref reader);
             return DeserializeRehydrationToken(document.RootElement, options);
         }
 
         BinaryData IPersistableModel<RehydrationToken>.Write(ModelReaderWriterOptions options)
-            => ModelReaderWriter.Write(this, options);
+        {
+            var format = options.Format == "W" ? ((IPersistableModel<RehydrationToken>)this).GetFormatFromOptions(options) : options.Format;
+
+            switch (format)
+            {
+                case "J":
+                    return ModelReaderWriter.Write(this, options);
+                default:
+                    throw new FormatException($"The model {nameof(RehydrationToken)} does not support '{options.Format}' format.");
+            }
+        }
 
         RehydrationToken IPersistableModel<RehydrationToken>.Create(BinaryData data, ModelReaderWriterOptions options)
         {
-            using var document = JsonDocument.Parse(data);
-            return DeserializeRehydrationToken(document.RootElement, options);
+            var format = options.Format == "W" ? ((IPersistableModel<RehydrationToken>)this).GetFormatFromOptions(options) : options.Format;
+
+            switch (format)
+            {
+                case "J":
+                    {
+                        using JsonDocument document = JsonDocument.Parse(data);
+                        return DeserializeRehydrationToken(document.RootElement, options);
+                    }
+                default:
+                    throw new FormatException($"The model {nameof(RehydrationToken)} does not support '{options.Format}' format.");
+            }
         }
 
         string IPersistableModel<RehydrationToken>.GetFormatFromOptions(ModelReaderWriterOptions options) => "J";
+
+        BinaryData IPersistableModel<object>.Write(ModelReaderWriterOptions options)
+            => ((IPersistableModel<RehydrationToken>)this).Write(options);
+
+        object IPersistableModel<object>.Create(BinaryData data, ModelReaderWriterOptions options)
+            => ((IPersistableModel<RehydrationToken>)this).Create(data, options);
+
+        string IPersistableModel<object>.GetFormatFromOptions(ModelReaderWriterOptions options) => "J";
+
+        void IJsonModel<object>.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options)
+            => ((IJsonModel<RehydrationToken>)this).Write(writer, options);
+
+        object IJsonModel<object>.Create(ref Utf8JsonReader reader, ModelReaderWriterOptions options)
+            => ((IJsonModel<RehydrationToken>)this).Create(ref reader, options);
     }
 }
diff --git a/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs b/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs
new file mode 100644
index 000000000000..b2fc4000544a
--- /dev/null
+++ b/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs
@@ -0,0 +1,34 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System;
+using System.ClientModel.Primitives;
+using NUnit.Framework;
+
+namespace Azure.Core.Tests
+{
+    public class RehydrationTokenTests
+    {
+        [Test]
+        public void ThrowOnDeserializationWithNullRehydrationToken()
+        {
+            Assert.Throws<InvalidOperationException>(() => new RehydrationToken().DeserializeRehydrationToken(default, new ModelReaderWriterOptions("J")));
+        }
+
+        [Test]
+        public void ThrowOnDeserializationWithRehydrationTokenNullRequiredMember()
+        {
+            var data = BinaryData.FromString("{'requestMethod': null}".Replace('\'', '\"'));
+            Assert.That(() => ModelReaderWriter.Read(data, typeof(RehydrationToken)), Throws.Exception);
+        }
+
+        [Test]
+        public void RoundTripForRehydrationToken()
+        {
+            var token = new RehydrationToken(Guid.NewGuid().ToString(), null, "headerSource", "nextRequestUri", "initialUri", RequestMethod.Get, "lastKnownLocation", OperationFinalStateVia.OperationLocation.ToString());
+            var data = ModelReaderWriter.Write(token);
+            var deserializedToken = ModelReaderWriter.Read(data, typeof(RehydrationToken));
+            Assert.AreEqual(token, deserializedToken);
+        }
+    }
+}

From ea2348b58bd37cdfd39668ec8f4833f07db9dbdb Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Thu, 8 Feb 2024 16:17:49 +0800
Subject: [PATCH 15/16] update API

---
 sdk/core/Azure.Core/api/Azure.Core.net461.cs         | 7 ++++++-
 sdk/core/Azure.Core/api/Azure.Core.net472.cs         | 7 ++++++-
 sdk/core/Azure.Core/api/Azure.Core.net6.0.cs         | 7 ++++++-
 sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs | 7 ++++++-
 4 files changed, 24 insertions(+), 4 deletions(-)

diff --git a/sdk/core/Azure.Core/api/Azure.Core.net461.cs b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
index c51499d7d22e..956318e726c3 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net461.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net461.cs
@@ -520,16 +520,21 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IJsonModel<object>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<object>
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
         public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        object System.ClientModel.Primitives.IJsonModel<object>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<object>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        object System.ClientModel.Primitives.IPersistableModel<object>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<object>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<object>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
     }
     public abstract partial class Request : System.IDisposable
     {
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net472.cs b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
index c51499d7d22e..956318e726c3 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net472.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net472.cs
@@ -520,16 +520,21 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IJsonModel<object>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<object>
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
         public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        object System.ClientModel.Primitives.IJsonModel<object>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<object>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        object System.ClientModel.Primitives.IPersistableModel<object>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<object>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<object>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
     }
     public abstract partial class Request : System.IDisposable
     {
diff --git a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
index e5ae8ee52ec7..df2f51671bc3 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.net6.0.cs
@@ -520,16 +520,21 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IJsonModel<object>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<object>
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
         public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        object System.ClientModel.Primitives.IJsonModel<object>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<object>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        object System.ClientModel.Primitives.IPersistableModel<object>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<object>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<object>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
     }
     public abstract partial class Request : System.IDisposable
     {
diff --git a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
index c51499d7d22e..956318e726c3 100644
--- a/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
+++ b/sdk/core/Azure.Core/api/Azure.Core.netstandard2.0.cs
@@ -520,16 +520,21 @@ public static partial class MultipartResponse
         public static System.Threading.Tasks.Task<Azure.Response[]> ParseAsync(Azure.Response response, bool expectCrLf, System.Threading.CancellationToken cancellationToken) { throw null; }
     }
     [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
-    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>
+    public readonly partial struct RehydrationToken : System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IJsonModel<object>, System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>, System.ClientModel.Primitives.IPersistableModel<object>
     {
         private readonly object _dummy;
         private readonly int _dummyPrimitive;
         public string? Id { get { throw null; } }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         void System.ClientModel.Primitives.IJsonModel<Azure.Core.RehydrationToken>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
+        object System.ClientModel.Primitives.IJsonModel<object>.Create(ref System.Text.Json.Utf8JsonReader reader, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        void System.ClientModel.Primitives.IJsonModel<object>.Write(System.Text.Json.Utf8JsonWriter writer, System.ClientModel.Primitives.ModelReaderWriterOptions options) { }
         Azure.Core.RehydrationToken System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         string System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
         System.BinaryData System.ClientModel.Primitives.IPersistableModel<Azure.Core.RehydrationToken>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        object System.ClientModel.Primitives.IPersistableModel<object>.Create(System.BinaryData data, System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        string System.ClientModel.Primitives.IPersistableModel<object>.GetFormatFromOptions(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
+        System.BinaryData System.ClientModel.Primitives.IPersistableModel<object>.Write(System.ClientModel.Primitives.ModelReaderWriterOptions options) { throw null; }
     }
     public abstract partial class Request : System.IDisposable
     {

From 5fe92c419f96a6008bda5cb56712facf202b3dd2 Mon Sep 17 00:00:00 2001
From: Wei Hu <huwe@microsoft.com>
Date: Tue, 20 Feb 2024 09:45:18 +0800
Subject: [PATCH 16/16] minor

---
 sdk/core/Azure.Core/tests/RehydrationTokenTests.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs b/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs
index b2fc4000544a..b93551c6454a 100644
--- a/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs
+++ b/sdk/core/Azure.Core/tests/RehydrationTokenTests.cs
@@ -18,7 +18,7 @@ public void ThrowOnDeserializationWithNullRehydrationToken()
         [Test]
         public void ThrowOnDeserializationWithRehydrationTokenNullRequiredMember()
         {
-            var data = BinaryData.FromString("{'requestMethod': null}".Replace('\'', '\"'));
+            var data = BinaryData.FromString("\"requestMethod\": null}");
             Assert.That(() => ModelReaderWriter.Read(data, typeof(RehydrationToken)), Throws.Exception);
         }