| #region Copyright notice and license |
| |
| // Copyright 2015 gRPC authors. |
| // |
| // 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 |
| // |
| // http://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. |
| |
| #endregion |
| |
| using System; |
| using System.Collections; |
| using System.Collections.Generic; |
| using System.IO; |
| using System.Linq; |
| using System.Threading.Tasks; |
| using Grpc.Core.Internal; |
| using Grpc.Core.Logging; |
| using Grpc.Core.Utils; |
| |
| namespace Grpc.Core |
| { |
| /// <summary> |
| /// gRPC server. A single server can serve an arbitrary number of services and can listen on more than one port. |
| /// </summary> |
| public class Server |
| { |
| const int DefaultRequestCallTokensPerCq = 2000; |
| static readonly ILogger Logger = GrpcEnvironment.Logger.ForType<Server>(); |
| |
| readonly AtomicCounter activeCallCounter = new AtomicCounter(); |
| |
| readonly ServiceDefinitionCollection serviceDefinitions; |
| readonly ServerPortCollection ports; |
| readonly GrpcEnvironment environment; |
| readonly List<ChannelOption> options; |
| readonly ServerSafeHandle handle; |
| readonly object myLock = new object(); |
| |
| readonly List<ServerServiceDefinition> serviceDefinitionsList = new List<ServerServiceDefinition>(); |
| readonly List<ServerPort> serverPortList = new List<ServerPort>(); |
| readonly Dictionary<string, IServerCallHandler> callHandlers = new Dictionary<string, IServerCallHandler>(); |
| readonly TaskCompletionSource<object> shutdownTcs = new TaskCompletionSource<object>(); |
| |
| bool startRequested; |
| volatile bool shutdownRequested; |
| int requestCallTokensPerCq = DefaultRequestCallTokensPerCq; |
| |
| /// <summary> |
| /// Creates a new server. |
| /// </summary> |
| public Server() : this(null) |
| { |
| } |
| |
| /// <summary> |
| /// Creates a new server. |
| /// </summary> |
| /// <param name="options">Channel options.</param> |
| public Server(IEnumerable<ChannelOption> options) |
| { |
| this.serviceDefinitions = new ServiceDefinitionCollection(this); |
| this.ports = new ServerPortCollection(this); |
| this.environment = GrpcEnvironment.AddRef(); |
| this.options = options != null ? new List<ChannelOption>(options) : new List<ChannelOption>(); |
| using (var channelArgs = ChannelOptions.CreateChannelArgs(this.options)) |
| { |
| this.handle = ServerSafeHandle.NewServer(channelArgs); |
| } |
| |
| foreach (var cq in environment.CompletionQueues) |
| { |
| this.handle.RegisterCompletionQueue(cq); |
| } |
| GrpcEnvironment.RegisterServer(this); |
| } |
| |
| /// <summary> |
| /// Services that will be exported by the server once started. Register a service with this |
| /// server by adding its definition to this collection. |
| /// </summary> |
| public ServiceDefinitionCollection Services |
| { |
| get |
| { |
| return serviceDefinitions; |
| } |
| } |
| |
| /// <summary> |
| /// Ports on which the server will listen once started. Register a port with this |
| /// server by adding its definition to this collection. |
| /// </summary> |
| public ServerPortCollection Ports |
| { |
| get |
| { |
| return ports; |
| } |
| } |
| |
| /// <summary> |
| /// To allow awaiting termination of the server. |
| /// </summary> |
| public Task ShutdownTask |
| { |
| get |
| { |
| return shutdownTcs.Task; |
| } |
| } |
| |
| /// <summary> |
| /// Experimental API. Might anytime change without prior notice. |
| /// Number or calls requested via grpc_server_request_call at any given time for each completion queue. |
| /// </summary> |
| public int RequestCallTokensPerCompletionQueue |
| { |
| get |
| { |
| return requestCallTokensPerCq; |
| } |
| set |
| { |
| lock (myLock) |
| { |
| GrpcPreconditions.CheckState(!startRequested); |
| GrpcPreconditions.CheckArgument(value > 0); |
| requestCallTokensPerCq = value; |
| } |
| } |
| } |
| |
| /// <summary> |
| /// Starts the server. |
| /// Throws <c>IOException</c> if not successful. |
| /// </summary> |
| public void Start() |
| { |
| lock (myLock) |
| { |
| GrpcPreconditions.CheckState(!startRequested); |
| GrpcPreconditions.CheckState(!shutdownRequested); |
| startRequested = true; |
| |
| CheckPortsBoundSuccessfully(); |
| handle.Start(); |
| |
| for (int i = 0; i < requestCallTokensPerCq; i++) |
| { |
| foreach (var cq in environment.CompletionQueues) |
| { |
| AllowOneRpc(cq); |
| } |
| } |
| } |
| } |
| |
| /// <summary> |
| /// Requests server shutdown and when there are no more calls being serviced, |
| /// cleans up used resources. The returned task finishes when shutdown procedure |
| /// is complete. |
| /// </summary> |
| /// <remarks> |
| /// It is strongly recommended to shutdown all previously created servers before exiting from the process. |
| /// </remarks> |
| public Task ShutdownAsync() |
| { |
| return ShutdownInternalAsync(false); |
| } |
| |
| /// <summary> |
| /// Requests server shutdown while cancelling all the in-progress calls. |
| /// The returned task finishes when shutdown procedure is complete. |
| /// </summary> |
| /// <remarks> |
| /// It is strongly recommended to shutdown all previously created servers before exiting from the process. |
| /// </remarks> |
| public Task KillAsync() |
| { |
| return ShutdownInternalAsync(true); |
| } |
| |
| internal void AddCallReference(object call) |
| { |
| activeCallCounter.Increment(); |
| |
| bool success = false; |
| handle.DangerousAddRef(ref success); |
| GrpcPreconditions.CheckState(success); |
| } |
| |
| internal void RemoveCallReference(object call) |
| { |
| handle.DangerousRelease(); |
| activeCallCounter.Decrement(); |
| } |
| |
| /// <summary> |
| /// Shuts down the server. |
| /// </summary> |
| private async Task ShutdownInternalAsync(bool kill) |
| { |
| lock (myLock) |
| { |
| GrpcPreconditions.CheckState(!shutdownRequested); |
| shutdownRequested = true; |
| } |
| GrpcEnvironment.UnregisterServer(this); |
| |
| var cq = environment.CompletionQueues.First(); // any cq will do |
| handle.ShutdownAndNotify(HandleServerShutdown, cq); |
| if (kill) |
| { |
| handle.CancelAllCalls(); |
| } |
| await ShutdownCompleteOrEnvironmentDeadAsync().ConfigureAwait(false); |
| |
| DisposeHandle(); |
| |
| await GrpcEnvironment.ReleaseAsync().ConfigureAwait(false); |
| } |
| |
| /// <summary> |
| /// In case the environment's threadpool becomes dead, the shutdown completion will |
| /// never be delivered, but we need to release the environment's handle anyway. |
| /// </summary> |
| private async Task ShutdownCompleteOrEnvironmentDeadAsync() |
| { |
| while (true) |
| { |
| var task = await Task.WhenAny(shutdownTcs.Task, Task.Delay(20)).ConfigureAwait(false); |
| if (shutdownTcs.Task == task) |
| { |
| return; |
| } |
| if (!environment.IsAlive) |
| { |
| return; |
| } |
| } |
| } |
| |
| /// <summary> |
| /// Adds a service definition. |
| /// </summary> |
| private void AddServiceDefinitionInternal(ServerServiceDefinition serviceDefinition) |
| { |
| lock (myLock) |
| { |
| GrpcPreconditions.CheckState(!startRequested); |
| foreach (var entry in serviceDefinition.CallHandlers) |
| { |
| callHandlers.Add(entry.Key, entry.Value); |
| } |
| serviceDefinitionsList.Add(serviceDefinition); |
| } |
| } |
| |
| /// <summary> |
| /// Adds a listening port. |
| /// </summary> |
| private int AddPortInternal(ServerPort serverPort) |
| { |
| lock (myLock) |
| { |
| GrpcPreconditions.CheckNotNull(serverPort.Credentials, "serverPort"); |
| GrpcPreconditions.CheckState(!startRequested); |
| var address = string.Format("{0}:{1}", serverPort.Host, serverPort.Port); |
| int boundPort; |
| using (var nativeCredentials = serverPort.Credentials.ToNativeCredentials()) |
| { |
| if (nativeCredentials != null) |
| { |
| boundPort = handle.AddSecurePort(address, nativeCredentials); |
| } |
| else |
| { |
| boundPort = handle.AddInsecurePort(address); |
| } |
| } |
| var newServerPort = new ServerPort(serverPort, boundPort); |
| this.serverPortList.Add(newServerPort); |
| return boundPort; |
| } |
| } |
| |
| /// <summary> |
| /// Allows one new RPC call to be received by server. |
| /// </summary> |
| private void AllowOneRpc(CompletionQueueSafeHandle cq) |
| { |
| if (!shutdownRequested) |
| { |
| // TODO(jtattermusch): avoid unnecessary delegate allocation |
| handle.RequestCall((success, ctx) => HandleNewServerRpc(success, ctx, cq), cq); |
| } |
| } |
| |
| /// <summary> |
| /// Checks that all ports have been bound successfully. |
| /// </summary> |
| private void CheckPortsBoundSuccessfully() |
| { |
| lock (myLock) |
| { |
| var unboundPort = ports.FirstOrDefault(port => port.BoundPort == 0); |
| if (unboundPort != null) |
| { |
| throw new IOException( |
| string.Format("Failed to bind port \"{0}:{1}\"", unboundPort.Host, unboundPort.Port)); |
| } |
| } |
| } |
| |
| private void DisposeHandle() |
| { |
| var activeCallCount = activeCallCounter.Count; |
| if (activeCallCount > 0) |
| { |
| Logger.Warning("Server shutdown has finished but there are still {0} active calls for that server.", activeCallCount); |
| } |
| handle.Dispose(); |
| } |
| |
| /// <summary> |
| /// Selects corresponding handler for given call and handles the call. |
| /// </summary> |
| private async Task HandleCallAsync(ServerRpcNew newRpc, CompletionQueueSafeHandle cq, Action continuation) |
| { |
| try |
| { |
| IServerCallHandler callHandler; |
| if (!callHandlers.TryGetValue(newRpc.Method, out callHandler)) |
| { |
| callHandler = UnimplementedMethodCallHandler.Instance; |
| } |
| await callHandler.HandleCall(newRpc, cq).ConfigureAwait(false); |
| } |
| catch (Exception e) |
| { |
| Logger.Warning(e, "Exception while handling RPC."); |
| } |
| finally |
| { |
| continuation(); |
| } |
| } |
| |
| /// <summary> |
| /// Handles the native callback. |
| /// </summary> |
| private void HandleNewServerRpc(bool success, RequestCallContextSafeHandle ctx, CompletionQueueSafeHandle cq) |
| { |
| bool nextRpcRequested = false; |
| if (success) |
| { |
| var newRpc = ctx.GetServerRpcNew(this); |
| |
| // after server shutdown, the callback returns with null call |
| if (!newRpc.Call.IsInvalid) |
| { |
| nextRpcRequested = true; |
| |
| // Start asynchronous handler for the call. |
| // Don't await, the continuations will run on gRPC thread pool once triggered |
| // by cq.Next(). |
| #pragma warning disable 4014 |
| HandleCallAsync(newRpc, cq, () => AllowOneRpc(cq)); |
| #pragma warning restore 4014 |
| } |
| } |
| |
| if (!nextRpcRequested) |
| { |
| AllowOneRpc(cq); |
| } |
| } |
| |
| /// <summary> |
| /// Handles native callback. |
| /// </summary> |
| private void HandleServerShutdown(bool success, BatchContextSafeHandle ctx, object state) |
| { |
| shutdownTcs.SetResult(null); |
| } |
| |
| /// <summary> |
| /// Collection of service definitions. |
| /// </summary> |
| public class ServiceDefinitionCollection : IEnumerable<ServerServiceDefinition> |
| { |
| readonly Server server; |
| |
| internal ServiceDefinitionCollection(Server server) |
| { |
| this.server = server; |
| } |
| |
| /// <summary> |
| /// Adds a service definition to the server. This is how you register |
| /// handlers for a service with the server. Only call this before Start(). |
| /// </summary> |
| public void Add(ServerServiceDefinition serviceDefinition) |
| { |
| server.AddServiceDefinitionInternal(serviceDefinition); |
| } |
| |
| /// <summary> |
| /// Gets enumerator for this collection. |
| /// </summary> |
| public IEnumerator<ServerServiceDefinition> GetEnumerator() |
| { |
| return server.serviceDefinitionsList.GetEnumerator(); |
| } |
| |
| IEnumerator IEnumerable.GetEnumerator() |
| { |
| return server.serviceDefinitionsList.GetEnumerator(); |
| } |
| } |
| |
| /// <summary> |
| /// Collection of server ports. |
| /// </summary> |
| public class ServerPortCollection : IEnumerable<ServerPort> |
| { |
| readonly Server server; |
| |
| internal ServerPortCollection(Server server) |
| { |
| this.server = server; |
| } |
| |
| /// <summary> |
| /// Adds a new port on which server should listen. |
| /// Only call this before Start(). |
| /// <returns>The port on which server will be listening.</returns> |
| /// </summary> |
| public int Add(ServerPort serverPort) |
| { |
| return server.AddPortInternal(serverPort); |
| } |
| |
| /// <summary> |
| /// Adds a new port on which server should listen. |
| /// <returns>The port on which server will be listening.</returns> |
| /// </summary> |
| /// <param name="host">the host</param> |
| /// <param name="port">the port. If zero, an unused port is chosen automatically.</param> |
| /// <param name="credentials">credentials to use to secure this port.</param> |
| public int Add(string host, int port, ServerCredentials credentials) |
| { |
| return Add(new ServerPort(host, port, credentials)); |
| } |
| |
| /// <summary> |
| /// Gets enumerator for this collection. |
| /// </summary> |
| public IEnumerator<ServerPort> GetEnumerator() |
| { |
| return server.serverPortList.GetEnumerator(); |
| } |
| |
| IEnumerator IEnumerable.GetEnumerator() |
| { |
| return server.serverPortList.GetEnumerator(); |
| } |
| } |
| } |
| } |