Add documentation (#79)

Signed-off-by: Gabriele Santomaggio <[email protected]>

README.md

@@ -1,22 +1,26 @@
 # RabbitMQ AMQP 1.0 .NET Client
 
 This library is meant to be used with RabbitMQ 4.0.
-Still work in progress suitable for testing in pre-production environments
+Suitable for testing in pre-production environments
 
-## How to Run
 
-- Start the broker with `./.ci/ubuntu/one-node/gha-setup.sh start`. Note that this has been tested on Ubuntu 22 with docker.
-- Run the tests with ` dotnet test ./Build.csproj  --logger "console;verbosity=detailed"`
-- Stop RabbitMQ with `./.ci/ubuntu/one-node/gha-setup.sh stop`
+## Install
 
-## Getting Started
+The client is distributed via [NuGet](https://www.nuget.org/packages/RabbitMQ.AMQP.Client/).
 
-You can find an example in: `docs/Examples/GettingStarted`
+## Examples
 
-## Install
+Inside the `docs/Examples` directory you can find examples of how to use the client.
 
-The client is distributed via [NuGet](https://www.nuget.org/packages/RabbitMQ.AMQP.Client/).
 
 ## Documentation
 
+- [Client Guide](https://www.rabbitmq.com/client-libraries/amqp-client-libraries)
 - [API](https://rabbitmq.github.io/rabbitmq-amqp-dotnet-client/api/RabbitMQ.AMQP.Client.html)
+
+
+## How to Run
+
+- Start the broker with `./.ci/ubuntu/one-node/gha-setup.sh start`. Note that this has been tested on Ubuntu 22 with docker.
+- Run the tests with ` dotnet test ./Build.csproj  --logger "console;verbosity=detailed"`
+- Stop RabbitMQ with `./.ci/ubuntu/one-node/gha-setup.sh stop`

RabbitMQ.AMQP.Client/IRpcClient.cs

@@ -10,23 +10,89 @@ public interface IRpcClientAddressBuilder : IAddressBuilder<IRpcClientAddressBui
         IRpcClientBuilder RpcClient();
     }
 
+    /// <summary>
+    /// IRpcClientBuilder is the interface for creating an RPC client.
+    /// See also <seealso cref="IRpcClient"/> and <seealso cref="IRpcServerBuilder"/>
+    /// </summary>
     public interface IRpcClientBuilder
     {
+        /// <summary>
+        /// Request address where the client sends requests.
+        /// The server consumes requests from this address.
+        /// </summary>
+        /// <returns></returns>
         IRpcClientAddressBuilder RequestAddress();
+
+        /// <summary>
+        /// The queue from which requests are consumed.
+        /// if not set the client will create a temporary queue.
+        /// </summary>
+        /// <param name="replyToQueueName"> The queue name</param>
+        /// <returns></returns>
         IRpcClientBuilder ReplyToQueue(string replyToQueueName);
 
         IRpcClientBuilder ReplyToQueue(IQueueSpecification replyToQueue);
+
+        /// <summary>
+        /// Extracts the correlation id from the request message.
+        /// each message has a correlation id that is used to match the request with the response.
+        /// There are default implementations for the correlation id extractor.
+        /// With this method, you can provide a custom implementation.
+        /// </summary>
+        /// <param name="correlationIdExtractor"></param>
+        /// <returns></returns>
         IRpcClientBuilder CorrelationIdExtractor(Func<IMessage, object>? correlationIdExtractor);
 
+        /// <summary>
+        /// Post processes the reply message before sending it to the server.
+        /// The object parameter is the correlation id extracted from the request message.
+        /// There are default implementations for the reply post processor that use the correlationId() field
+        /// to set the correlation id of the reply message.
+        /// With this method, you can provide a custom implementation.
+        /// </summary>
+        /// <param name="requestPostProcessor"></param>
+        /// <returns></returns>
         IRpcClientBuilder RequestPostProcessor(Func<IMessage, object, IMessage>? requestPostProcessor);
 
+        /// <summary>
+        /// Client and Server must agree on the correlation id.
+        /// The client will provide the correlation id to send to the server.
+        /// If the default correlation id is not suitable, you can provide a custom correlation id supplier.
+        /// Be careful to provide a unique correlation id for each request. 
+        /// </summary>
+        /// <param name="correlationIdSupplier"></param>
+        /// <returns></returns>
+
         IRpcClientBuilder CorrelationIdSupplier(Func<object>? correlationIdSupplier);
+
+        /// <summary>
+        /// The time to wait for a reply from the server.
+        /// </summary>
+        /// <param name="timeout"></param>
+        /// <returns></returns>
         IRpcClientBuilder Timeout(TimeSpan timeout);
+        /// <summary>
+        ///  Build and return the RPC client.
+        /// </summary>
+        /// <returns></returns>
         Task<IRpcClient> BuildAsync();
     }
 
+    /// <summary>
+    ///  IRpcClient is the interface for an RPC client.
+    /// See also <seealso cref="IRpcServer"/> and <seealso cref="IRpcClientBuilder"/>
+    /// </summary>
     public interface IRpcClient : ILifeCycle
     {
+        /// <summary>
+        /// PublishAsync sends a request message to the server and blocks the thread until the response is received.
+        /// The PublishAsync is thread-safe and can be called from multiple threads.
+        /// The Function returns the response message.
+        /// If the server does not respond within the timeout, the function throws a TimeoutException.
+        /// </summary>
+        /// <param name="message"> The request message</param>
+        /// <param name="cancellationToken">Cancellation token</param>
+        /// <returns></returns>
         Task<IMessage> PublishAsync(IMessage message, CancellationToken cancellationToken = default);
     }
 }

RabbitMQ.AMQP.Client/IRpcServer.cs

@@ -3,8 +3,12 @@
 
 namespace RabbitMQ.AMQP.Client
 {
-    public delegate Task<IMessage> RpcHandler(IRpcServer.IContext context, IMessage request);
 
+    /// <summary>
+    /// IRpcServerBuilder is the interface for creating an RPC server.
+    /// The RPC server consumes requests from a queue and sends replies to a reply queue.
+    /// See also <seealso cref="IRpcServer"/>  and <seealso cref="IRpcClientBuilder"/>
+    /// </summary>
     public interface IRpcServerBuilder
     {
         /// <summary>
@@ -45,9 +49,25 @@ public interface IRpcServerBuilder
         /// <returns></returns>
         IRpcServerBuilder Handler(RpcHandler handler);
 
+        /// <summary>
+        /// Build and return the RPC server.
+        /// </summary>
+        /// <returns></returns>
         Task<IRpcServer> BuildAsync();
     }
 
+    /// <summary>
+    /// Event handler for handling RPC requests.
+    /// </summary>
+    public delegate Task<IMessage> RpcHandler(IRpcServer.IContext context, IMessage request);
+
+    /// <summary>
+    /// IRpcServer interface for creating an RPC server.
+    /// The RPC is simulated by sending a request message and receiving a reply message.
+    /// Where the client sends the queue where wants to receive the reply.
+    /// RPC client ---> request queue ---> RPC server ---> reply queue ---> RPC client
+    /// See also <seealso cref="IRpcClient"/>
+    /// </summary>
     public interface IRpcServer : ILifeCycle
     {
 

RabbitMQ.AMQP.Client/Impl/AmqpRpcClient.cs

@@ -188,12 +188,6 @@ public override async Task CloseAsync()
             }
         }
 
-        /// <summary>
-        /// PublishAsync sends a request message to the server and blocks the thread until the response is received.
-        /// </summary>
-        /// <param name="message"> The request message</param>
-        /// <param name="cancellationToken">Cancellation token</param>
-        /// <returns></returns>
         public async Task<IMessage> PublishAsync(IMessage message, CancellationToken cancellationToken = default)
         {
             await _semaphore.WaitAsync(cancellationToken).ConfigureAwait(false);

RabbitMQ.AMQP.Client/Impl/AmqpRpcServer.cs

@@ -151,7 +151,7 @@ await Utils.WaitWithBackOffUntilFuncAsync(async () =>
                                 {
                                     Trace.WriteLine(TraceLevel.Error, $"Failed to send reply, retrying in {span}");
                                 }
-                            }, 3).ConfigureAwait(false);
+                            }, 5).ConfigureAwait(false);
                     }
                 })
                 .Queue(_configuration.RequestQueue).BuildAndStartAsync()

Tests/Rpc/RpcServerTests.cs

@@ -318,5 +318,41 @@ public async Task RpcClientMultiThreadShouldBeSafe()
             await rpcServer.CloseAsync();
             await rpcClient.CloseAsync();
         }
+
+        /// <summary>
+        /// The RPC client `PublishAsync` should raise a timeout exception if the server does not reply within the timeout
+        /// </summary>
+        [Fact]
+        public async Task RpcClientShouldRaiseTimeoutError()
+        {
+            Assert.NotNull(_connection);
+            Assert.NotNull(_management);
+            string requestQueue = _queueName;
+            await _management.Queue(requestQueue).Exclusive(true).AutoDelete(true).DeclareAsync();
+            IRpcServer rpcServer = await _connection.RpcServerBuilder().Handler((context, request) =>
+            {
+                var reply = context.Message("pong");
+                object millisecondsToWait = request.ApplicationProperty("wait");
+                Thread.Sleep(TimeSpan.FromMilliseconds((int)millisecondsToWait));
+                return Task.FromResult(reply);
+            }).RequestQueue(_queueName).BuildAsync();
+            Assert.NotNull(rpcServer);
+
+            IRpcClient rpcClient = await _connection.RpcClientBuilder().RequestAddress()
+                .Queue(requestQueue)
+                .RpcClient()
+                .Timeout(TimeSpan.FromMilliseconds(300))
+                .BuildAsync();
+
+            IMessage reply = await rpcClient.PublishAsync(
+                new AmqpMessage("ping").ApplicationProperty("wait", 1));
+            Assert.Equal("pong", reply.Body());
+
+            await Assert.ThrowsAsync<TimeoutException>(() => rpcClient.PublishAsync(
+                new AmqpMessage("ping").ApplicationProperty("wait", 700)));
+
+            await rpcClient.CloseAsync();
+            await rpcServer.CloseAsync();
+        }
     }
 }

docs/Examples/README.md

@@ -0,0 +1,8 @@
+# RabbitMQ AMQP 1.0 .NET Client examples
+
+This directory contains examples of how to use the RabbitMQ AMQP 1.0 .NET client.
+
+- Getting Started with the Client [here](./GettingStarted/)
+- RPC Server and Client [here](./Rpc/)
+- How to write a reliable client [here](./HAClient/)
+- Performance Test [here](./PerformanceTest/). You can tune some parameters in the `Program.cs` file.