[ECO-5650] Added a way to inject external HTTP client, updated tests for the same

Author: sacOO7

.github/workflows/package.yml

@@ -89,7 +89,7 @@ jobs:
             ${{ github.workspace }}/*.nupkg
 
   package-push:
-    runs-on: macos-13
+    runs-on: macos-14
     env:
       DOTNET_NOLOGO: true
 

.github/workflows/run-tests-macos-mono.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   check:
-    runs-on: macos-13
+    runs-on: macos-14
     env:
       DOTNET_NOLOGO: true
 

.github/workflows/run-tests-macos.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   check:
-    runs-on: macos-13
+    runs-on: macos-14
     env:
       DOTNET_NOLOGO: true
 

src/IO.Ably.Shared/ClientOptions.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Net.Http;
 using System.Threading;
 using IO.Ably.Transport;
 using Newtonsoft.Json;
@@ -413,6 +414,16 @@ public bool UseBinaryProtocol
         /// </summary>
         public Dictionary<string, string> Agents { get; set; }
 
+        /// <summary>
+        /// Allows injection of an externally managed HttpClient instance.
+        /// When provided, the library will use this HttpClient instead of creating its own.
+        /// This enables proper HttpClient lifecycle management and connection pooling.
+        /// The injected HttpClient should be configured with appropriate timeouts and handlers.
+        /// Default: null (library creates its own HttpClient).
+        /// </summary>
+        [JsonIgnore]
+        public HttpClient HttpClient { get; set; }
+
         [JsonIgnore]
         internal Func<DateTimeOffset> NowFunc
         {

src/IO.Ably.Shared/Http/AblyHttpClient.cs

@@ -14,12 +14,12 @@ internal class AblyHttpClient : IAblyHttpClient
         private readonly Random _random = new Random();
         private string _realtimeConnectedFallbackHost;
 
-        internal AblyHttpClient(AblyHttpOptions options, HttpMessageHandler messageHandler = null)
+        internal AblyHttpClient(AblyHttpOptions options)
         {
             Now = options.NowFunc;
             Logger = options.Logger ?? DefaultLogger.LoggerInstance;
             Options = options;
-            CreateInternalHttpClient(options.HttpRequestTimeout, messageHandler);
+            CreateInternalHttpClient(options.HttpRequestTimeout, options.HttpClient);
             SendAsync = InternalSendAsync;
         }
 
@@ -68,11 +68,22 @@ internal void SetPreferredHost(string currentHost)
             }
         }
 
-        internal void CreateInternalHttpClient(TimeSpan timeout, HttpMessageHandler messageHandler)
+        internal void CreateInternalHttpClient(TimeSpan timeout, HttpClient externalHttpClient = null)
         {
-            Client = messageHandler != null ? new HttpClient(messageHandler) : new HttpClient();
-            Client.DefaultRequestHeaders.Add("X-Ably-Version", Defaults.ProtocolVersion); // RSC7a
-            Client.DefaultRequestHeaders.Add(Agent.AblyAgentHeader, Agent.AblyAgentIdentifier(Options.Agents)); // RSC7d
+            Client = externalHttpClient ?? new HttpClient();
+
+            // RSC7a
+            if (!Client.DefaultRequestHeaders.Contains("X-Ably-Version"))
+            {
+                Client.DefaultRequestHeaders.Add("X-Ably-Version", Defaults.ProtocolVersion);
+            }
+
+            // RSC7d
+            if (!Client.DefaultRequestHeaders.Contains(Agent.AblyAgentHeader))
+            {
+                Client.DefaultRequestHeaders.Add(Agent.AblyAgentHeader, Agent.AblyAgentIdentifier(Options.Agents));
+            }
+
             Client.Timeout = timeout;
         }
 

src/IO.Ably.Shared/Http/AblyHttpOptions.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Net.Http;
 
 namespace IO.Ably
 {
@@ -37,6 +38,8 @@ internal class AblyHttpOptions
 
         public Dictionary<string, string> Agents { get; set; }
 
+        public HttpClient HttpClient { get; set; }
+
         public AblyHttpOptions()
         {
             // Used for testing
@@ -73,6 +76,7 @@ public AblyHttpOptions(ClientOptions options)
             FallbackHostsUseDefault = options.FallbackHostsUseDefault;
             AddRequestIds = options.AddRequestIds;
             Agents = options.Agents;
+            HttpClient = options.HttpClient;
 
             NowFunc = options.NowFunc;
             Logger = options.Logger;

src/IO.Ably.Tests.Shared/AuthTests/AuthSandboxSpecs.cs

@@ -62,7 +62,7 @@ public async Task RestClient_WhenTokenExpired_ShouldNotRetryAndRaiseError(Protoc
             // Get a very short lived token and wait for it to expire
             var authClient = await GetRestClient(protocol);
             var almostExpiredToken = await authClient.AblyAuth.RequestTokenAsync(new TokenParams { ClientId = "123", Ttl = TimeSpan.FromMilliseconds(1) });
-            await Task.Delay(TimeSpan.FromMilliseconds(2));
+            await Task.Delay(TimeSpan.FromMilliseconds(500));
 
             // Modify the expiry date to fool the client it has a valid token
             almostExpiredToken.Expires = DateTimeOffset.UtcNow.AddHours(1);

src/IO.Ably.Tests.Shared/Infrastructure/AblyRealtimeSpecs.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 using FluentAssertions;
@@ -75,13 +76,12 @@ private static AblyRealtime GetRealtimeClientWithFakeMessageHandler(ClientOption
         {
             var clientOptions = options ?? new ClientOptions(ValidKey);
             clientOptions.SkipInternetCheck = true; // This is for the Unit tests
-            var client = new AblyRealtime(clientOptions, mobileDevice);
             if (fakeMessageHandler != null)
             {
-                client.RestClient.HttpClient.CreateInternalHttpClient(TimeSpan.FromSeconds(10), fakeMessageHandler);
+                clientOptions.HttpClient = new HttpClient(fakeMessageHandler);
             }
 
-            return client;
+            return new AblyRealtime(clientOptions, mobileDevice);
         }
 
         internal AblyRealtime GetRealtimeClient(Action<ClientOptions> optionsAction, Func<AblyRequest, Task<AblyResponse>> handleRequestFunc = null)

src/IO.Ably.Tests.Shared/Rest/AblyHttpClientSpecs.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Linq;
 using System.Net;
 using System.Net.Http;
@@ -41,7 +42,7 @@ public async Task WhenCallingUrl_AddsDefaultAblyLibraryVersionHeader()
         {
             var response = new HttpResponseMessage(HttpStatusCode.Accepted) { Content = new StringContent("Success") };
             var handler = new FakeHttpMessageHandler(response);
-            var client = new AblyHttpClient(new AblyHttpOptions(), handler);
+            var client = new AblyHttpClient(new AblyHttpOptions { HttpClient = new HttpClient(handler) });
 
             await client.Execute(new AblyRequest("/test", HttpMethod.Get));
             var values = handler.LastRequest.Headers.GetValues("X-Ably-Version").ToArray();
@@ -55,7 +56,7 @@ public async Task WhenCallingUrl_AddsRequestIdIfSetTrue()
         {
             var response = new HttpResponseMessage(HttpStatusCode.Accepted) { Content = new StringContent("Success") };
             var handler = new FakeHttpMessageHandler(response);
-            var client = new AblyHttpClient(new AblyHttpOptions { AddRequestIds = true }, handler);
+            var client = new AblyHttpClient(new AblyHttpOptions { AddRequestIds = true, HttpClient = new HttpClient(handler) });
             var ablyRequest = new AblyRequest("/test", HttpMethod.Get);
             ablyRequest.AddHeaders(new Dictionary<string, string> { { "request_id", "custom_request_id" } });
             await client.Execute(ablyRequest);
@@ -69,7 +70,7 @@ public async Task WhenCallingUrlWithPostParamsAndEmptyBody_PassedTheParamsAsUrlE
         {
             var response = new HttpResponseMessage(HttpStatusCode.Accepted) { Content = new StringContent("Success") };
             var handler = new FakeHttpMessageHandler(response);
-            var client = new AblyHttpClient(new AblyHttpOptions(), handler);
+            var client = new AblyHttpClient(new AblyHttpOptions { HttpClient = new HttpClient(handler) });
 
             var ablyRequest = new AblyRequest("/test", HttpMethod.Post)
             {
@@ -88,7 +89,7 @@ public async Task WhenCallingUrl_AddsDefaultAblyAgentHeader()
         {
             var response = new HttpResponseMessage(HttpStatusCode.Accepted) { Content = new StringContent("Success") };
             var handler = new FakeHttpMessageHandler(response);
-            var client = new AblyHttpClient(new AblyHttpOptions(), handler);
+            var client = new AblyHttpClient(new AblyHttpOptions { HttpClient = new HttpClient(handler) });
 
             await client.Execute(new AblyRequest("/test", HttpMethod.Get));
             string[] values = handler.LastRequest.Headers.GetValues("Ably-Agent").ToArray();
@@ -127,9 +128,10 @@ public async Task WhenCallingUrl_AddsCustomizedAblyAgentHeader()
                     { "agent1", "value1" },
                     { "agent2", "value2" },
                 },
+                HttpClient = new HttpClient(handler)
             };
 
-            var client = new AblyHttpClient(ablyHttpOptions, handler);
+            var client = new AblyHttpClient(ablyHttpOptions);
 
             await client.Execute(new AblyRequest("/test", HttpMethod.Get));
             string[] values = handler.LastRequest.Headers.GetValues("Ably-Agent").ToArray();
@@ -190,5 +192,88 @@ public void IsRetryableResponse_WithErrorCode_ShouldReturnExpectedValue(
                 AblyHttpClient.IsRetryableResponse(response).Should().Be(expected);
             }
         }
+
+        public class ExternalHttpClientSpecs
+        {
+            [Fact]
+            public void WithExternalHttpClient_ShouldUseProvidedClient()
+            {
+                // Arrange
+                var externalHttpClient = new HttpClient();
+                var options = new AblyHttpOptions { HttpClient = externalHttpClient };
+
+                // Act
+                var ablyHttpClient = new AblyHttpClient(options);
+
+                // Assert
+                ablyHttpClient.Client.Should().BeSameAs(externalHttpClient);
+            }
+
+            [Fact]
+            public void WithExternalHttpClient_ShouldStillAddAblyHeaders()
+            {
+                // Arrange
+                var externalHttpClient = new HttpClient();
+                var options = new AblyHttpOptions { HttpClient = externalHttpClient };
+
+                // Act
+                var ablyHttpClient = new AblyHttpClient(options);
+
+                // Assert
+                ablyHttpClient.Client.DefaultRequestHeaders.Contains("X-Ably-Version").Should().BeTrue();
+                ablyHttpClient.Client.DefaultRequestHeaders.Contains("Ably-Agent").Should().BeTrue();
+            }
+
+            [Fact]
+            public void WithExternalHttpClient_ShouldSetTimeout()
+            {
+                // Arrange
+                var externalHttpClient = new HttpClient();
+                var timeout = TimeSpan.FromSeconds(30);
+                var options = new AblyHttpOptions
+                {
+                    HttpClient = externalHttpClient,
+                    HttpRequestTimeout = timeout
+                };
+
+                // Act
+                var ablyHttpClient = new AblyHttpClient(options);
+
+                // Assert
+                ablyHttpClient.Client.Timeout.Should().Be(timeout);
+            }
+
+            [Fact]
+            public void WithoutExternalHttpClient_ShouldCreateNewClient()
+            {
+                // Arrange
+                var options = new AblyHttpOptions();
+                options.HttpClient.Should().BeNull();
+
+                // Act
+                var ablyHttpClient = new AblyHttpClient(options);
+
+                // Assert
+                ablyHttpClient.Client.Should().NotBeNull();
+            }
+
+            [Fact]
+            public async Task WithExternalHttpClient_ShouldMakeSuccessfulRequests()
+            {
+                // Arrange
+                var response = new HttpResponseMessage(HttpStatusCode.Accepted) { Content = new StringContent("Success") };
+                var handler = new FakeHttpMessageHandler(response);
+                var externalHttpClient = new HttpClient(handler);
+                var options = new AblyHttpOptions { HttpClient = externalHttpClient };
+                var ablyHttpClient = new AblyHttpClient(options);
+
+                // Act
+                var result = await ablyHttpClient.Execute(new AblyRequest("/test", HttpMethod.Get));
+
+                // Assert
+                result.StatusCode.Should().Be(HttpStatusCode.Accepted);
+                handler.NumberOfRequests.Should().Be(1);
+            }
+        }
     }
 }