feat: Added IServiceCollection extension methods for PublisherClient …

…and SubscriberClient

apis/Google.Cloud.PubSub.V1/Google.Cloud.PubSub.V1.Tests/Google.Cloud.PubSub.V1.Tests.csproj

@@ -11,6 +11,7 @@
     <PackageReference Include="Google.Apis.CloudResourceManager.v1" Version="[1.57.0.2677, 2.0.0.0)" />
     <ProjectReference Include="..\..\..\tools\Google.Cloud.ClientTesting\Google.Cloud.ClientTesting.csproj" />
     <ProjectReference Include="..\Google.Cloud.PubSub.V1\Google.Cloud.PubSub.V1.csproj" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="6.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.4.1" />
     <PackageReference Include="Moq" Version="4.18.4" />
     <PackageReference Include="System.Linq.Async" Version="6.0.1" />

apis/Google.Cloud.PubSub.V1/Google.Cloud.PubSub.V1.Tests/ServiceCollectionExtensionsTest.cs

@@ -0,0 +1,185 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License").
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at 
+//
+// https://www.apache.org/licenses/LICENSE-2.0 
+//
+// Unless required by applicable law or agreed to in writing, software 
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and 
+// limitations under the License.
+
+using Google.Apis.Auth.OAuth2;
+using Grpc.Auth;
+using Microsoft.Extensions.DependencyInjection;
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using Xunit;
+
+namespace Google.Cloud.PubSub.V1.Tests;
+
+public class ServiceCollectionExtensionsTest
+{
+    [Fact]
+    public void AddPublisherClient_WithTopicName()
+    {
+        // Arrange.
+        TopicName topicName = TopicName.FromProjectTopic("projectId", "topicId");
+        IServiceCollection serviceCollection = new ServiceCollection();
+        // As Application Default Credentials are not available for unit tests, we need to pass a fake credential.
+        serviceCollection.AddSingleton(new FakeCredential().ToChannelCredentials());
+
+        // Act.
+        serviceCollection.AddPublisherClient(topicName);
+        var provider = serviceCollection.BuildServiceProvider();
+        var client = provider.GetService<PublisherClient>();
+
+        // Assert.
+        Assert.NotNull(client);
+        Assert.Equal(topicName, client.TopicName);
+    }
+
+    [Fact]
+    public void AddPublisherClient_WithAction()
+    {
+        // Arrange.
+        TopicName topicName = TopicName.FromProjectTopic("projectId", "topicId");
+        IServiceCollection serviceCollection = new ServiceCollection();
+        // As Application Default Credentials are not available for unit tests, we need to pass a fake credential.
+        serviceCollection.AddSingleton(new FakeCredential().ToChannelCredentials());
+
+        // Act.
+        serviceCollection.AddPublisherClient(builder => builder.TopicName = topicName);
+        var provider = serviceCollection.BuildServiceProvider();
+        var client = provider.GetService<PublisherClient>();
+
+        // Assert.
+        Assert.NotNull(client);
+        Assert.Equal(topicName, client.TopicName);
+    }
+
+    [Fact]
+    public void AddPublisherClient_WithAction_NoTopicName()
+    {
+        // Arrange.
+        IServiceCollection serviceCollection = new ServiceCollection();
+        serviceCollection.AddSingleton(new FakeCredential().ToChannelCredentials());
+
+        // Act.
+        serviceCollection.AddPublisherClient(builder => { });
+        var provider = serviceCollection.BuildServiceProvider();
+
+        // Assert.
+        // When TopicName isn't specified, it results in an InvalidOperationException.
+        Assert.Throws<InvalidOperationException>(provider.GetRequiredService<PublisherClient>);
+    }
+
+    [Fact]
+    public void AddPublisherClient_WithNullTopicName()
+    {
+        // Arrange.
+        // Passing null topicName to AddPublisherClient should throw ArgumentNullException.
+        IServiceCollection serviceCollection = new ServiceCollection();
+
+        // Act and Assert.
+        Assert.Throws<ArgumentNullException>(() => serviceCollection.AddPublisherClient(topicName: null));
+    }
+
+    [Fact]
+    public void AddPublisherClient_WithNullAction()
+    {
+        // Arrange.
+        // Passing null action to AddPublisherClient should throw ArgumentNullException.
+        IServiceCollection serviceCollection = new ServiceCollection();
+
+        // Act and assert.
+        Assert.Throws<ArgumentNullException>(() => serviceCollection.AddPublisherClient(action: null));
+    }
+
+    [Fact]
+    public void AddSubscriberClient_WithTopicName()
+    {
+        // Arrange.
+        SubscriptionName subscriptionName = SubscriptionName.FromProjectSubscription("projectId", "subscriptionId");
+        IServiceCollection serviceCollection = new ServiceCollection();
+        // As Application Default Credentials are not available for unit tests, we need to pass a fake credential.
+        serviceCollection.AddSingleton(new FakeCredential().ToChannelCredentials());
+
+        // Act.
+        serviceCollection.AddSubscriberClient(subscriptionName);
+        var provider = serviceCollection.BuildServiceProvider();
+        var client = provider.GetService<SubscriberClient>();
+
+        // Assert.
+        Assert.NotNull(client);
+        Assert.Equal(subscriptionName, client.SubscriptionName);
+    }
+
+    [Fact]
+    public void AddSubscriberClient_WithAction()
+    {
+        // Arrange.
+        SubscriptionName subscriptionName = SubscriptionName.FromProjectSubscription("projectId", "subscriptionId");
+        IServiceCollection serviceCollection = new ServiceCollection();
+        // As Application Default Credentials are not available for unit tests, we need to pass a fake credential.
+        serviceCollection.AddSingleton(new FakeCredential().ToChannelCredentials());
+
+        // Act.
+        serviceCollection.AddSubscriberClient(builder => builder.SubscriptionName = subscriptionName);
+        var provider = serviceCollection.BuildServiceProvider();
+        var client = provider.GetService<SubscriberClient>();
+
+        // Assert.
+        Assert.NotNull(client);
+        Assert.Equal(subscriptionName, client.SubscriptionName);
+    }
+
+    [Fact]
+    public void AddSubscriberClient_WithAction_NoSubscriptionName()
+    {
+        // Arrange.
+        // When SubscriptionName isn't specified in the builder, it should result in an InvalidOperationException.
+        IServiceCollection serviceCollection = new ServiceCollection();
+
+        //Act.
+        serviceCollection.AddSubscriberClient(builder => { });
+        var provider = serviceCollection.BuildServiceProvider();
+
+        // Assert.
+        Assert.Throws<InvalidOperationException>(provider.GetRequiredService<SubscriberClient>);
+    }
+
+    [Fact]
+    public void AddSubscriberClient_WithNullSubscriptionName()
+    {
+        // Arrange.
+        // Passing null subscriptionName to AddSubscriberClient should throw ArgumentNullException.
+        IServiceCollection serviceCollection = new ServiceCollection();
+
+        // Act and assert.
+        Assert.Throws<ArgumentNullException>(() => serviceCollection.AddSubscriberClient(subscriptionName: null));
+    }
+
+    [Fact]
+    public void AddSubscriberClient_WithNullAction()
+    {
+        // Arrange.
+        // Passing null action to AddSubscriberClient should throw ArgumentNullException.
+        IServiceCollection serviceCollection = new ServiceCollection();
+
+        // Act and assert.
+        Assert.Throws<ArgumentNullException>(() => serviceCollection.AddSubscriberClient(action: null));
+    }
+
+    // Fake credential used just to ensure that we don't fetch the application default credentials
+    // (which may not be available for unit tests).
+    private class FakeCredential : ITokenAccess
+    {
+        public Task<string> GetAccessTokenForRequestAsync(string authUri = null, CancellationToken cancellationToken = default) =>
+            throw new NotImplementedException();
+    }
+}

apis/Google.Cloud.PubSub.V1/Google.Cloud.PubSub.V1/ServiceCollectionExtensions.cs

@@ -0,0 +1,97 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License").
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at 
+//
+// https://www.apache.org/licenses/LICENSE-2.0 
+//
+// Unless required by applicable law or agreed to in writing, software 
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and 
+// limitations under the License.
+
+using Google.Api.Gax;
+using Google.Cloud.PubSub.V1;
+using System;
+
+namespace Microsoft.Extensions.DependencyInjection;
+
+/// <summary>
+/// Provides extension methods to configure dependency injection with PubSub.
+/// </summary>
+public static partial class ServiceCollectionExtensions
+{
+    /// <summary>
+    /// Adds a singleton <see cref="PublisherClient"/> to the <see cref="IServiceCollection"/> as customized by the <paramref name="action"/>.
+    /// </summary>
+    /// <param name="services">
+    /// The <see cref="IServiceCollection"/> to add the singleton client to.
+    /// </param>
+    /// <param name="action">
+    /// An action delegate to invoke on the <see cref="PublisherClientBuilder"/> for configuring the <see cref="PublisherClient"/>. This is invoked before <paramref name="services"/> are used.
+    /// Must not be null and at-least <see cref="PublisherClientBuilder.TopicName"/> must be set.
+    /// </param>
+    /// <returns>The updated <see cref="IServiceCollection"/>, for method chaining.</returns>
+    public static IServiceCollection AddPublisherClient(this IServiceCollection services, Action<PublisherClientBuilder> action)
+    {
+        GaxPreconditions.CheckNotNull(action, nameof(action));
+        return services.AddSingleton(provider =>
+        {
+            var builder = new PublisherClientBuilder();
+            action.Invoke(builder);
+            return builder.Build(provider);
+        });
+    }
+
+    /// <summary>
+    /// Adds a singleton <see cref="PublisherClient"/> associated with the specified <see cref="TopicName"/>, using default settings to the <see cref="IServiceCollection"/>.
+    /// </summary>
+    /// <param name="services">
+    /// The <see cref="IServiceCollection"/> to add the singleton client to.
+    /// </param>
+    /// <param name="topicName">The <see cref="TopicName"/> to publish messages to. Must not be null.</param>
+    /// <returns>The updated <see cref="IServiceCollection"/>, for method chaining.</returns>
+    public static IServiceCollection AddPublisherClient(this IServiceCollection services, TopicName topicName)
+    {
+        GaxPreconditions.CheckNotNull(topicName, nameof(topicName));
+        return services.AddPublisherClient(new Action<PublisherClientBuilder>(builder => builder.TopicName = topicName));
+    }
+
+    /// <summary>
+    /// Adds a singleton <see cref="SubscriberClient"/> to the <see cref="IServiceCollection"/> as customized by the <paramref name="action"/>.
+    /// </summary>
+    /// <param name="services">
+    /// The <see cref="IServiceCollection"/> to add the singleton client to.
+    /// </param>
+    /// <param name="action">
+    /// An action to invoke on the <see cref="SubscriberClientBuilder"/> for configuring the <see cref="SubscriberClient"/>. This is invoked before <paramref name="services"/> are used.
+    /// Must not be null and at-least <see cref="SubscriberClientBuilder.SubscriptionName"/> must be set.
+    /// </param>
+    /// <returns>The updated <see cref="IServiceCollection"/>, for method chaining.</returns>
+    public static IServiceCollection AddSubscriberClient(this IServiceCollection services, Action<SubscriberClientBuilder> action)
+    {
+        GaxPreconditions.CheckNotNull(action, nameof(action));
+        return services.AddSingleton(provider =>
+        {
+            var builder = new SubscriberClientBuilder();
+            action.Invoke(builder);
+            return builder.Build(provider);
+        });
+    }
+
+    /// <summary>
+    /// Adds a singleton <see cref="SubscriberClient"/> associated with the specified <see cref="SubscriptionName"/>, using default settings to the <see cref="IServiceCollection"/>.
+    /// </summary>
+    /// <param name="services">
+    /// The <see cref="IServiceCollection"/> to add the singleton client to.
+    /// </param>
+    /// <param name="subscriptionName">The <see cref="SubscriptionName"/> to receive messages from. Must not be null.</param>
+    /// <returns>The updated <see cref="IServiceCollection"/>, for method chaining.</returns>
+    public static IServiceCollection AddSubscriberClient(this IServiceCollection services, SubscriptionName subscriptionName)
+    {
+        GaxPreconditions.CheckNotNull(subscriptionName, nameof(subscriptionName));
+        return services.AddSubscriberClient(new Action<SubscriberClientBuilder>(builder => builder.SubscriptionName = subscriptionName));
+    }
+}