chore: Revert "feat: automatically generated instanceId (#226)" (#233)

* chore: Revert "feat: automatically generated instanceId (#226)"

* style: formatting

README.md

@@ -349,6 +349,7 @@ End Class
 
 Dim unleashSettings As New UnleashSettings()
 unleashSettings.AppName = "dotnet-test"
+unleashSettings.InstanceTag = "instance z"
 ' add the custom http header provider to the settings
 unleashSettings.UnleashCustomHttpHeaderProvider = New CustomHttpHeaderProvider()
 unleashSettings.UnleashApi = new Uri("http://unleash.herokuapp.com/api/")
@@ -424,13 +425,24 @@ By default unleash-client fetches the feature toggles from unleash-server every
 * When .json file does not exists
 * When the named feature toggle does not exist in .json file
 
-The backup file name will follow this pattern: `{fileNameWithoutExtension}-{AppName}-{SdkVersion}.{extension}`.
+The backup file name will follow this pattern: `{fileNameWithoutExtension}-{AppName}-{InstanceTag}-{SdkVersion}.{extension}`, where InstanceTag is either what you configure on `UnleashSettings` during startup, or a formatted string with a random component following this pattern: `{Dns.GetHostName()}-generated-{Guid.NewGuid()}`.
 
-### InstanceTag
+You can configure InstanceTag like this:
 
-As of version `5.0.0`, `InstanceTag` is no longer a property of `UnleashSettings`. Instead, an internal `InstanceId` is automatically generated.
-
-This means that the backup file names have been simplified and no longer include the `InstanceTag` property value.
+```csharp
+var settings = new UnleashSettings()
+{
+    AppName = "dotnet-test",
+    UnleashApi = new Uri("http://unleash.herokuapp.com/api/"),
+    // Set an instance tag for consistent backup file naming
+    InstanceTag = "CustomInstanceTag",
+    UnleashContextProvider = new AspNetContextProvider(),
+    CustomHttpHeaders = new Dictionary<string, string>()
+    {
+        {"Authorization", "API token" }
+    }
+};
+```
 
 ## Bootstrapping
 * Unleash supports bootstrapping from a JSON string.

samples/WebApp/Global.asax.cs

@@ -27,6 +27,7 @@ protected void Application_Start()
                 UnleashApi = new Uri("http://unleash.herokuapp.com/api/"),
                 //UnleashApi = new Uri("http://localhost:4242/api/"),
                 AppName = "dotnet-api-test",
+                InstanceTag = "instance 1",
                 SendMetricsInterval = TimeSpan.FromSeconds(20),
                 UnleashContextProvider = new AspNetContextProvider(),
                 //JsonSerializer = new JsonNetSerializer()

samples/WebApplication/Startup.cs

@@ -26,6 +26,7 @@ public void ConfigureServices(IServiceCollection services)
             {
                 UnleashApi = new Uri("http://localhost:4242/api"),
                 AppName = "variant-sample",
+                InstanceTag = "instance 1",
                 SendMetricsInterval = TimeSpan.FromSeconds(10),
                 FetchTogglesInterval = TimeSpan.FromSeconds(10),
             });

samples/WinFormsApp/Program.cs

@@ -33,6 +33,7 @@ static void Main()
                 UnleashApi = new Uri("http://unleash.herokuapp.com/api/"),
                 //UnleashApi = new Uri("http://localhost:4242/api/"),
                 AppName = "dotnet-forms-test",
+                InstanceTag = "instance 1",
                 SendMetricsInterval = TimeSpan.FromSeconds(5),
                 FetchTogglesInterval = TimeSpan.FromSeconds(10),
                 UnleashContextProvider = new WinFormsContextProvider(form),

src/Unleash/Communication/UnleashApiClient.cs

@@ -230,7 +230,7 @@ public async Task<bool> SendMetrics(ThreadSafeMetricsBucket metrics, Cancellatio
                 jsonSerializer.Serialize(memoryStream, new ClientMetrics
                 {
                     AppName = clientRequestHeaders.AppName,
-                    InstanceId = clientRequestHeaders.InstanceId,
+                    InstanceId = clientRequestHeaders.InstanceTag,
                     Bucket = bucket
                 });
             }
@@ -290,7 +290,7 @@ private static void SetRequestHeaders(HttpRequestMessage requestMessage, Unleash
 
             requestMessage.Headers.TryAddWithoutValidation(appNameHeader, headers.AppName);
             requestMessage.Headers.TryAddWithoutValidation(userAgentHeader, headers.AppName);
-            requestMessage.Headers.TryAddWithoutValidation(instanceIdHeader, headers.InstanceId);
+            requestMessage.Headers.TryAddWithoutValidation(instanceIdHeader, headers.InstanceTag);
             requestMessage.Headers.TryAddWithoutValidation(supportedSpecVersionHeader, headers.SupportedSpecVersion);
 
             SetCustomHeaders(requestMessage, headers.CustomHttpHeaders);

src/Unleash/Communication/UnleashApiClientRequestHeaders.cs

@@ -5,7 +5,7 @@ namespace Unleash.Communication
     internal class UnleashApiClientRequestHeaders
     {
         public string AppName { get; set; }
-        public string InstanceId { get; set; }
+        public string InstanceTag { get; set; }
         public Dictionary<string, string> CustomHttpHeaders { get; set; }
         public IUnleashCustomHttpHeaderProvider CustomHttpHeaderProvider { get; set; }
         public string SupportedSpecVersion { get; internal set; }

src/Unleash/Events/ErrorType.cs

@@ -1,8 +1,13 @@
-namespace Unleash.Events
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Unleash.Events
 {
     public enum ErrorType
     {
         Client,
+        TogglesBackup,
         Bootstrap,
         ImpressionEvent,
         FileCache

src/Unleash/Internal/UnleashServices.cs

@@ -62,7 +62,7 @@ public UnleashServices(UnleashSettings settings, EventCallbackConfig eventConfig
                 apiClient = new UnleashApiClient(httpClient, settings.JsonSerializer, new UnleashApiClientRequestHeaders()
                 {
                     AppName = settings.AppName,
-                    InstanceId = settings.InstanceId,
+                    InstanceTag = settings.InstanceTag,
                     CustomHttpHeaders = settings.CustomHttpHeaders,
                     CustomHttpHeaderProvider = settings.UnleashCustomHttpHeaderProvider,
                     SupportedSpecVersion = supportedSpecVersion

src/Unleash/Internal/UnleashSettingsValidator.cs

@@ -10,6 +10,9 @@ public void Validate(UnleashSettings settings)
             if (settings.AppName == null)
                 throw new UnleashException("You are required to specify an appName");
 
+            if (settings.InstanceTag == null)
+                throw new UnleashException("You are required to specify an instance id");
+
             if (settings.JsonSerializer == null)
                 throw new UnleashException("You are required to specify an json serializer");
 

src/Unleash/Scheduling/ClientRegistrationBackgroundTask.cs

@@ -34,7 +34,7 @@ public async Task ExecuteAsync(CancellationToken cancellationToken)
             var clientRegistration = new ClientRegistration
             {
                 AppName = settings.AppName,
-                InstanceId = settings.InstanceId,
+                InstanceId = settings.InstanceTag,
                 Interval = (long)settings.SendMetricsInterval.Value.TotalMilliseconds,
                 SdkVersion = settings.SdkVersion,
                 Started = DateTimeOffset.UtcNow,

src/Unleash/Scheduling/FetchFeatureTogglesTask.cs

@@ -89,6 +89,7 @@ public async Task ExecuteAsync(CancellationToken cancellationToken)
             catch (IOException ex)
             {
                 Logger.Warn(() => $"UNLEASH: Exception when writing to toggle file '{toggleFile}'.", ex);
+                eventConfig?.RaiseError(new ErrorEvent() { ErrorType = ErrorType.TogglesBackup, Error = ex });
             }
 
             Etag = result.Etag;
@@ -100,6 +101,7 @@ public async Task ExecuteAsync(CancellationToken cancellationToken)
             catch (IOException ex)
             {
                 Logger.Warn(() => $"UNLEASH: Exception when writing to ETag file '{etagFile}'.", ex);
+                eventConfig?.RaiseError(new ErrorEvent() { ErrorType = ErrorType.TogglesBackup, Error = ex });
             }
         }
 

src/Unleash/UnleashSettings.cs

@@ -46,9 +46,9 @@ public class UnleashSettings
         public string Environment { get; set; } = "default";
 
         /// <summary>
-        /// INTERNAL: Gets or sets an instance id. Used for communication with backend api.
+        /// Gets or sets an instance tag. Used for communication with backend api.
         /// </summary>
-        internal string InstanceId { get; set; } = Guid.NewGuid().ToString();
+        public string InstanceTag { get; set; } = GetDefaultInstanceTag();
 
         /// <summary>
         /// Sets the project to fetch feature toggles for.
@@ -155,6 +155,13 @@ private static string GetSdkVersion()
             return $"unleash-client-dotnet:v{version}";
         }
 
+        private static string GetDefaultInstanceTag()
+        {
+            var hostName = Dns.GetHostName();
+
+            return $"{hostName}-generated-{Guid.NewGuid()}";
+        }
+
         /// <summary>
         /// Returns info about the unleash setup.
         /// </summary>
@@ -164,7 +171,7 @@ public override string ToString()
 
             sb.AppendLine($"Application name: {AppName}");
             sb.AppendLine($"Environment: {Environment}");
-            sb.AppendLine($"Instance Id: {InstanceId}");
+            sb.AppendLine($"Instance tag: {InstanceTag}");
             sb.AppendLine($"Project Id: {ProjectId}");
             sb.AppendLine($"Server Uri: {UnleashApi}");
             sb.AppendLine($"Sdk version: {SdkVersion}");
@@ -208,7 +215,7 @@ private string PrependFileName(string filename)
             var extension = Path.GetExtension(filename);
             var fileNameWithoutExtension = Path.GetFileNameWithoutExtension(filename);
 
-            return new string($"{fileNameWithoutExtension}-{AppName}-{SdkVersion}{extension}"
+            return new string($"{fileNameWithoutExtension}-{AppName}-{InstanceTag}-{SdkVersion}{extension}"
                 .Where(c => !invalidFileNameChars.Contains(c))
                 .ToArray());
         }

tests/Unleash.Tests/ClientFactory/SyncStartupUnitTest.cs

@@ -24,7 +24,7 @@ public class SyncStartupUnitTest
         public void Setup()
         {
             mockApiClient = A.Fake<IUnleashApiClient>();
-            settings = new MockedUnleashSettings();
+            settings = new MockedUnleashSettings(instanceTag: "test instance SyncStartupUnitTest");
             unleashFactory = new UnleashClientFactory();
         }
 

tests/Unleash.Tests/Communication/CustomHeadersUnitTest.cs

@@ -24,6 +24,7 @@ private IUnleashApiClient CreateApiClient()
             var requestHeaders = new UnleashApiClientRequestHeaders
             {
                 AppName = "api-test-client",
+                InstanceTag = "instance1",
                 CustomHttpHeaders = httpHeaders,
                 CustomHttpHeaderProvider = httpHeadersProvider
             };

tests/Unleash.Tests/Communication/UnleashApiClient_Project_Tests.cs

@@ -27,6 +27,7 @@ private UnleashApiClient NewTestableClient(string project, MockHttpMessageHandle
             var requestHeaders = new UnleashApiClientRequestHeaders
             {
                 AppName = "api-test-client",
+                InstanceTag = "instance1",
                 CustomHttpHeaders = null,
                 CustomHttpHeaderProvider = null
             };

tests/Unleash.Tests/ExampleTests.cs

@@ -14,7 +14,7 @@ public class ExampleTests
         public async Task Setup()
         {
             var factory = new UnleashClientFactory();
-            unleash = await factory.CreateClientAsync(new MockedUnleashSettings(), true);
+            unleash = await factory.CreateClientAsync(new MockedUnleashSettings(instanceTag: "test instance ExampleTests"), true);
         }
 
         [Test]

tests/Unleash.Tests/IOTests.cs

@@ -24,7 +24,7 @@ private static void LockFile(object data)
         [Test]
         public async Task GracefullyFailsWhenFileLocked()
         {
-            var settings = new MockedUnleashSettings(false);
+            var settings = new MockedUnleashSettings(false, "test instance IOTests");
 
             var toggleFile = settings.GetFeatureToggleFilePath();
             var eTagFile = settings.GetFeatureToggleETagFilePath();

tests/Unleash.Tests/Internal/ErrorEvents_Tests.cs

@@ -116,6 +116,75 @@ public void FetchFeatureToggleTask_HttpRequestException_Raises_ErrorEvent()
             thrownException.Should().NotBeNull();
         }
 
+        [Test]
+        public void FetchFeatureToggleTask_Serialization_Throws_Raises_ErrorEvent()
+        {
+            // Arrange
+            ErrorEvent callbackEvent = null;
+            var exceptionMessage = "Serialization failed";
+            var callbackConfig = new EventCallbackConfig()
+            {
+                ErrorEvent = evt => { callbackEvent = evt; }
+            };
+
+            var fakeApiClient = A.Fake<IUnleashApiClient>();
+            A.CallTo(() => fakeApiClient.FetchToggles(A<string>._, A<CancellationToken>._, false))
+                .Returns(Task.FromResult(new FetchTogglesResult() { HasChanged = true, ToggleCollection = new ToggleCollection(), Etag = "one" }));
+
+            var collection = new ThreadSafeToggleCollection();
+            var serializer = A.Fake<IJsonSerializer>();
+            A.CallTo(() => serializer.Serialize(A<Stream>._, A<ToggleCollection>._))
+                .Throws(() => new IOException(exceptionMessage));
+
+            var filesystem = new MockFileSystem();
+            var tokenSource = new CancellationTokenSource();
+            var task = new FetchFeatureTogglesTask(fakeApiClient, collection, serializer, filesystem, callbackConfig, "togglefile.txt", "etagfile.txt", false);
+
+            // Act
+            Task.WaitAll(task.ExecuteAsync(tokenSource.Token));
+
+            // Assert
+            callbackEvent.Should().NotBeNull();
+            callbackEvent.Error.Should().NotBeNull();
+            callbackEvent.Error.Message.Should().Be(exceptionMessage);
+            callbackEvent.ErrorType.Should().Be(ErrorType.TogglesBackup);
+        }
+
+        [Test]
+        public void FetchFeatureToggleTask_Etag_Writing_Throws_Raises_ErrorEvent()
+        {
+            // Arrange
+            ErrorEvent callbackEvent = null;
+            var exceptionMessage = "Writing failed";
+            var callbackConfig = new EventCallbackConfig()
+            {
+                ErrorEvent = evt => { callbackEvent = evt; }
+            };
+
+            var fakeApiClient = A.Fake<IUnleashApiClient>();
+            A.CallTo(() => fakeApiClient.FetchToggles(A<string>._, A<CancellationToken>._, false))
+                .Returns(Task.FromResult(new FetchTogglesResult() { HasChanged = true, ToggleCollection = new ToggleCollection(), Etag = "one" }));
+
+            var collection = new ThreadSafeToggleCollection();
+            var serializer = A.Fake<IJsonSerializer>();
+
+            var filesystem = A.Fake<IFileSystem>();
+            A.CallTo(() => filesystem.WriteAllText(A<string>._, A<string>._))
+                .Throws(() => new IOException(exceptionMessage));
+
+            var tokenSource = new CancellationTokenSource();
+            var task = new FetchFeatureTogglesTask(fakeApiClient, collection, serializer, filesystem, callbackConfig, "togglefile.txt", "etagfile.txt", false);
+
+            // Act
+            Task.WaitAll(task.ExecuteAsync(tokenSource.Token));
+
+            // Assert
+            callbackEvent.Should().NotBeNull();
+            callbackEvent.Error.Should().NotBeNull();
+            callbackEvent.Error.Message.Should().Be(exceptionMessage);
+            callbackEvent.ErrorType.Should().Be(ErrorType.TogglesBackup);
+        }
+
         [Test]
         public void CachedFilesLoader_Raises_ErrorEvent()
         {

tests/Unleash.Tests/MockedUnleashSettings.cs

@@ -8,9 +8,10 @@ namespace Unleash.Tests
 {
     public class MockedUnleashSettings : UnleashSettings
     {
-        public MockedUnleashSettings(bool mockFileSystem = true)
+        public MockedUnleashSettings(bool mockFileSystem = true, string instanceTag = "test instance 1")
         {
             AppName = "test";
+            InstanceTag = instanceTag;
             UnleashApi = new Uri("http://localhost:4242/");
             DisableSingletonWarning = true;