feat: Allow configuring analytics API endpoint separate from flags API

Flagsmith.Client.Test/AnalyticsProcessorTest.cs

@@ -13,8 +13,8 @@ internal class AnalyticsProcessorTest : AnalyticsProcessor
         /// <summary>
         /// This class provides some extra functionality to help particularly in unit testing.
         /// </summary>
-        public AnalyticsProcessorTest(HttpClient httpClient, string environmentKey, string baseApiUrl, int timeOut = 3)
-            : base(httpClient, environmentKey, baseApiUrl, timeOut: timeOut)
+        public AnalyticsProcessorTest(HttpClient httpClient, string environmentKey, Uri analyticsUri, int timeOut = 3)
+            : base(httpClient, environmentKey, analyticsUri, timeOut: timeOut)
         {
         }
         /// <summary>

Flagsmith.Client.Test/AnalyticsTests.cs

@@ -14,7 +14,8 @@ namespace Flagsmith.FlagsmithClientTest
 {
     public class AnalyticsTests
     {
-        const string _defaultApiUrl = "https://edge.api.flagsmith.com/api/v1/";
+        static readonly Uri _defaultApiUri = new Uri("https://edge.api.flagsmith.com/api/v1/");
+        static readonly Uri _defaultAnalyticsUri = new Uri(_defaultApiUri, "analytics/flags/");
 
         [Fact]
         public async Task TestAnalyticsProcessorDoesNotThrowUnderLoad()
@@ -27,7 +28,7 @@ public async Task TestAnalyticsProcessorDoesNotThrowUnderLoad()
             HttpMocker.PayloadsSubmitted = new System.Collections.Concurrent.ConcurrentBag<string>();
 
             var mockHttpClient = HttpMocker.MockHttpResponse(System.Net.HttpStatusCode.OK, null, true);
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, null);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, _defaultAnalyticsUri);
             var token = new CancellationToken();
             await Parallel.ForEachAsync(Enumerable.Range(1, numberOfThreads), token, async (item, token) =>
             {
@@ -69,7 +70,7 @@ public async Task TestAnalyticsProcessorFlushClearsAnalyticsData()
             {
                 StatusCode = System.Net.HttpStatusCode.OK,
             });
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, null);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, _defaultAnalyticsUri);
             await analyticsProcessor.TrackFeature("TestAnalyticsProcessorFlushClearsAnalyticsDataFeature");
             await analyticsProcessor.Flush();
             Assert.False(analyticsProcessor.HasTrackingItemsInCache());
@@ -81,7 +82,7 @@ public async void TestAnalyticsProcessorFlushPostRequestDataMatchAnanlyticsData(
             {
                 StatusCode = System.Net.HttpStatusCode.OK,
             });
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, baseApiUrl: _defaultApiUrl);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, analyticsUri: _defaultAnalyticsUri);
             await analyticsProcessor.TrackFeature("TestAnalyticsProcessorFlushPostRequestDataMatchAnanlyticsDataFeature1");
             await analyticsProcessor.TrackFeature("TestAnalyticsProcessorFlushPostRequestDataMatchAnanlyticsDataFeature2");
             var jObject = JObject.Parse(analyticsProcessor.ToString());
@@ -91,13 +92,77 @@ public async void TestAnalyticsProcessorFlushPostRequestDataMatchAnanlyticsData(
             Assert.Equal(1, jObject["TestAnalyticsProcessorFlushPostRequestDataMatchAnanlyticsDataFeature2"].Value<int>());
         }
         [Fact]
+        public async Task TestAnalyticsProcessorPostsToConfiguredAnalyticsUri()
+        {
+            var mockHttpClient = HttpMocker.MockHttpResponse(new HttpResponseMessage
+            {
+                StatusCode = System.Net.HttpStatusCode.OK,
+            });
+            var analyticsUri = new Uri("https://analytics.example.com/api/v1/analytics/flags/");
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, Fixtures.ApiKey, analyticsUri);
+            await analyticsProcessor.TrackFeature("some_feature");
+            await analyticsProcessor.Flush();
+            mockHttpClient.Verify(x => x.SendAsync(
+                It.Is<HttpRequestMessage>(req => req.Method == HttpMethod.Post && req.RequestUri == analyticsUri),
+                It.IsAny<CancellationToken>()), Times.Once);
+        }
+        [Fact]
+        public async Task TestAnalyticsProcessorBaseApiUrlConstructorPostsToAnalyticsEndpoint()
+        {
+            var mockHttpClient = HttpMocker.MockHttpResponse(new HttpResponseMessage
+            {
+                StatusCode = System.Net.HttpStatusCode.OK,
+            });
+            var analyticsProcessor = new AnalyticsProcessor(mockHttpClient.Object, Fixtures.ApiKey, _defaultApiUri.ToString());
+            await analyticsProcessor.TrackFeature("some_feature");
+            await analyticsProcessor.Flush();
+            VerifyAnalyticsPostedTo(mockHttpClient, _defaultAnalyticsUri);
+        }
+        [Fact]
+        public async Task TestFlagsmithClientPostsAnalyticsToExpectedUri()
+        {
+            var customAnalyticsUri = new Uri("https://analytics.example.com/api/v1/analytics/flags/");
+            // A client using the default analytics endpoint, relative to the API URI...
+            var (defaultUriMock, defaultUriFlags) = await GetClientFlags(analyticsUri: null);
+            // ...and a client with an analytics endpoint configured separately from the API URI
+            var (customUriMock, customUriFlags) = await GetClientFlags(customAnalyticsUri);
+            await Task.Delay(11 * 1000);
+            await defaultUriFlags.IsFeatureEnabled("some_feature");
+            await customUriFlags.IsFeatureEnabled("some_feature");
+            // Tracking a feature does not await the flush it triggers, so give the requests time to be made
+            await Task.Delay(2 * 1000);
+            VerifyAnalyticsPostedTo(defaultUriMock, _defaultAnalyticsUri);
+            VerifyAnalyticsPostedTo(customUriMock, customAnalyticsUri);
+        }
+        private static async Task<(Mock<HttpClient>, IFlags)> GetClientFlags(Uri analyticsUri)
+        {
+            var mockHttpClient = HttpMocker.MockHttpResponse(new HttpResponseMessage
+            {
+                StatusCode = System.Net.HttpStatusCode.OK,
+                Content = new StringContent(Fixtures.ApiFlagResponse)
+            });
+            var client = new FlagsmithClient(new FlagsmithConfiguration
+            {
+                EnvironmentKey = Fixtures.ApiKey,
+                ApiUri = _defaultApiUri,
+                AnalyticsUri = analyticsUri,
+                HttpClient = mockHttpClient.Object,
+                EnableAnalytics = true
+            });
+            return (mockHttpClient, await client.GetEnvironmentFlags());
+        }
+        private static void VerifyAnalyticsPostedTo(Mock<HttpClient> mockHttpClient, Uri expectedUri)
+            => mockHttpClient.Verify(x => x.SendAsync(
+                It.Is<HttpRequestMessage>(req => req.Method == HttpMethod.Post && req.RequestUri == expectedUri),
+                It.IsAny<CancellationToken>()), Times.Once);
+        [Fact]
         public async Task TestAnalyticsProcessorFlushEarlyExitIfAnalyticsDataIsEmpty()
         {
             var mockHttpClient = HttpMocker.MockHttpResponse(new HttpResponseMessage
             {
                 StatusCode = System.Net.HttpStatusCode.OK,
             });
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, baseApiUrl: _defaultApiUrl);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, analyticsUri: _defaultAnalyticsUri);
             await analyticsProcessor.Flush();
             mockHttpClient.Verify(x => x.SendAsync(It.IsAny<HttpRequestMessage>(), It.IsAny<CancellationToken>()), Times.Never);
         }
@@ -108,7 +173,7 @@ public async Task TestAnalyticsProcessorCallingTrackFeatureCallsFlushWhenTimerRu
             {
                 StatusCode = System.Net.HttpStatusCode.OK,
             });
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, baseApiUrl: _defaultApiUrl);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, analyticsUri: _defaultAnalyticsUri);
             await Task.Delay(12 * 1000);
             await analyticsProcessor.TrackFeature("TestAnalyticsProcessorCallingTrackFeatureCallsFlushWhenTimerRunsOutFeature");
             mockHttpClient.VerifyHttpRequest(HttpMethod.Post, "/api/v1/analytics/flags/", Times.Once);
@@ -122,7 +187,7 @@ public async Task TestAnalyticsProcessorDataConcurrentAccess()
             {
                 StatusCode = System.Net.HttpStatusCode.OK,
             });
-            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, null);
+            var analyticsProcessor = new AnalyticsProcessorTest(mockHttpClient.Object, null, _defaultAnalyticsUri);
             const int numberOfCalls = 100000;
 
             // When 

Flagsmith.Client.Test/Fixtures.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Net.Http;
 using FlagsmithEngine.Environment.Models;
@@ -10,7 +11,8 @@ internal class Fixtures
     {
         public static string ApiKey => "ser.test_key";
         public static string ApiUrl => "http://test_url/";
-        public static AnalyticsProcessorTest GetAnalyticalProcessorTest() => new(new HttpClient(), ApiKey, ApiUrl);
+        public static Uri AnalyticsUri => new Uri(ApiUrl + "analytics/flags/");
+        public static AnalyticsProcessorTest GetAnalyticalProcessorTest() => new(new HttpClient(), ApiKey, AnalyticsUri);
         public static JObject JsonObject = JObject.Parse(@"{
   'api_key': 'test_key',
   'name': 'Test Environment',

Flagsmith.Client.Test/UserAgentTest.cs

@@ -113,7 +113,7 @@ public async Task TestUserAgentHeaderIsSentInAnalyticsFlush()
             var analyticsProcessor = new AnalyticsProcessor(
                 httpClientMock.Object,
                 Fixtures.ApiKey,
-                Fixtures.ApiUrl
+                Fixtures.AnalyticsUri
             );
 
             // When

Flagsmith.FlagsmithClient/AnalyticsProcessor.cs

@@ -18,7 +18,7 @@ public class AnalyticsProcessor : IAnalyticsProcessor
 
         private int _FlushIntervalSeconds = 10;
         private readonly DisposableLock _lock = new DisposableLock();
-        private readonly string _AnalyticsEndPoint;
+        private readonly Uri _AnalyticsUri;
         private readonly string _EnvironmentKey;
         private readonly int _TimeOut;
         private DateTime _LastFlushed;
@@ -28,9 +28,14 @@ public class AnalyticsProcessor : IAnalyticsProcessor
         private ConcurrentDictionary<string, Dictionary<string, int>> AnalyticsDataThreads;
 
         public AnalyticsProcessor(HttpClient httpClient, string environmentKey, string baseApiUrl, ILogger logger = null, Dictionary<string, string> customHeaders = null, int timeOut = 3, int flushIntervalSeconds = 10)
+            : this(httpClient, environmentKey, new Uri(baseApiUrl + "analytics/flags/", UriKind.RelativeOrAbsolute), logger, customHeaders, timeOut, flushIntervalSeconds)
+        {
+        }
+
+        public AnalyticsProcessor(HttpClient httpClient, string environmentKey, Uri analyticsUri, ILogger logger = null, Dictionary<string, string> customHeaders = null, int timeOut = 3, int flushIntervalSeconds = 10)
         {
             _EnvironmentKey = environmentKey;
-            _AnalyticsEndPoint = baseApiUrl + "analytics/flags/";
+            _AnalyticsUri = analyticsUri;
             _TimeOut = timeOut;
             _LastFlushed = DateTime.UtcNow;
             _HttpClient = httpClient;
@@ -71,7 +76,7 @@ private async Task FlushWithoutLock()
             try
             {
                 var analyticsJson = JsonConvert.SerializeObject(GetAggregatedAnalyticsWithoutLock());
-                var request = new HttpRequestMessage(HttpMethod.Post, _AnalyticsEndPoint)
+                var request = new HttpRequestMessage(HttpMethod.Post, _AnalyticsUri)
                 {
                     Headers =
                         {

Flagsmith.FlagsmithClient/FlagsmithClient.cs

@@ -70,7 +70,7 @@ private void Initialise()
                     throw new Exception("ValueError: environmentKey is required");
                 }
                 if (_config.EnableAnalytics)
-                    _analyticsProcessor = new AnalyticsProcessor(_config.HttpClient, _config.EnvironmentKey, _config.ApiUri.ToString(), _config.Logger, _config.CustomHeaders);
+                    _analyticsProcessor = new AnalyticsProcessor(_config.HttpClient, _config.EnvironmentKey, _config.AnalyticsUri ?? new Uri(_config.ApiUri, "analytics/flags/"), _config.Logger, _config.CustomHeaders);
 
                 if (_config.EnableLocalEvaluation)
                 {

Flagsmith.FlagsmithClient/FlagsmithConfiguration.cs

@@ -19,10 +19,18 @@
         /// </summary>
         public Uri ApiUri { get; set; } = DefaultApiUri;
 
+        /// <summary>
+        /// URI of the Flagsmith analytics events API endpoint. Set this when analytics are not served by the same
+        /// API as flags, e.g. when using Edge Proxy. Defaults to the <c>analytics/flags/</c> endpoint relative to
+        /// <see cref="ApiUri"/>.
+        /// <example><code>new Uri("https://flagsmith.example.com/api/v1/analytics/flags/")</code></example>
+        /// </summary>
+        public Uri? AnalyticsUri { get; set; }
+
         /// <summary>
         /// The environment key obtained from Flagsmith interface.
         /// </summary>
         public string EnvironmentKey { get; set; }
 
         /// <summary>
         /// Enables local evaluation of flags.
@@ -42,7 +50,7 @@
         /// <summary>
         /// Provide logger for logging polling info & errors which is only applicable when client side evalution is enabled and analytics errors.
         /// </summary>
         public ILogger Logger { get; set; }
 
         /// <summary>
         /// if enabled, sends additional requests to the Flagsmith API to power flag analytics charts.
@@ -66,7 +74,7 @@
         /// <summary>
         /// Additional headers to add to requests made to the Flagsmith API
         /// </summary>
         public Dictionary<string, string> CustomHeaders { get; set; }
 
         /// <summary>
         /// If enabled, the SDK will cache the flags for the duration specified in the CacheConfig