/// <summary>
/// Try to process the request using the server. Returns a null-containing Task if a response
/// from the server cannot be retrieved.
/// </summary>
private static async Task <ServerResponse> TryProcessRequest(
Client client,
ServerRequest request,
CancellationToken cancellationToken)
{
ServerResponse response;
using (client)
{
// Write the request
try
{
ServerLogger.Log("Begin writing request");
await request.WriteAsync(client.Stream, cancellationToken).ConfigureAwait(false);
ServerLogger.Log("End writing request");
}
catch (Exception e)
{
ServerLogger.LogException(e, "Error writing build request.");
return(new RejectedServerResponse());
}
// Wait for the compilation and a monitor to detect if the server disconnects
var serverCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
ServerLogger.Log("Begin reading response");
var responseTask = ServerResponse.ReadAsync(client.Stream, serverCts.Token);
var monitorTask = client.WaitForDisconnectAsync(serverCts.Token);
await Task.WhenAny(new[] { responseTask, monitorTask }).ConfigureAwait(false);
ServerLogger.Log("End reading response");
if (responseTask.IsCompleted)
{
// await the task to log any exceptions
try
{
response = await responseTask.ConfigureAwait(false);
}
catch (Exception e)
{
ServerLogger.LogException(e, "Error reading response");
response = new RejectedServerResponse();
}
}
else
{
ServerLogger.Log("Server disconnect");
response = new RejectedServerResponse();
}
// Cancel whatever task is still around
serverCts.Cancel();
Debug.Assert(response != null);
return(response);
}
}
internal static async Task <ServerResponse> Send(string pipeName, ServerRequest request)
{
using (var client = await Client.ConnectAsync(pipeName, timeout: null, cancellationToken: default).ConfigureAwait(false))
{
await request.WriteAsync(client.Stream).ConfigureAwait(false);
return(await ServerResponse.ReadAsync(client.Stream).ConfigureAwait(false));
}
}
protected async override Task <int> ExecuteCoreAsync()
{
if (!IsServerRunning())
{
// server isn't running right now
Out.Write("Server is not running.");
return(0);
}
try
{
using (var client = await Client.ConnectAsync(Pipe.Value(), timeout: TimeSpan.FromSeconds(5), cancellationToken: Cancelled))
{
if (client == null)
{
throw new InvalidOperationException("Couldn't connect to the server.");
}
var request = ServerRequest.CreateShutdown();
await request.WriteAsync(client.Stream, Cancelled).ConfigureAwait(false);
var response = ((ShutdownServerResponse)await ServerResponse.ReadAsync(client.Stream, Cancelled));
if (Wait.HasValue())
{
try
{
var process = Process.GetProcessById(response.ServerProcessId);
process.WaitForExit();
}
catch (Exception ex)
{
// There is an inherent race here with the server process. If it has already shutdown
// by the time we try to access it then the operation has succeeded.
Error.Write(ex);
}
Out.Write("Server pid:{0} shut down completed.", response.ServerProcessId);
}
}
}
catch (Exception ex) when(IsServerRunning())
{
// Ignore an exception that occurred while the server was shutting down.
Error.Write(ex);
}
return(0);
}
public async Task ServerResponse_WriteRead_RoundtripsProperly()
{
// Arrange
var response = new CompletedServerResponse(42, utf8output: false, output: "a string", error: "an error");
var memoryStream = new MemoryStream();
// Act
await response.WriteAsync(memoryStream, CancellationToken.None);
// Assert
Assert.True(memoryStream.Position > 0);
memoryStream.Position = 0;
var result = (CompletedServerResponse)await ServerResponse.ReadAsync(memoryStream, CancellationToken.None);
Assert.Equal(42, result.ReturnCode);
Assert.False(result.Utf8Output);
Assert.Equal("a string", result.Output);
Assert.Equal("an error", result.ErrorOutput);
}
public async Task ShutdownResponse_WriteRead_RoundtripsProperly()
{
// Arrange & Act 1
var memoryStream = new MemoryStream();
var response = new ShutdownServerResponse(42);
// Assert 1
Assert.Equal(ServerResponse.ResponseType.Shutdown, response.Type);
// Act 2
await response.WriteAsync(memoryStream, CancellationToken.None);
// Assert 2
memoryStream.Position = 0;
var read = await ServerResponse.ReadAsync(memoryStream, CancellationToken.None);
Assert.Equal(ServerResponse.ResponseType.Shutdown, read.Type);
var typed = (ShutdownServerResponse)read;
Assert.Equal(42, typed.ServerProcessId);
}
public async Task AcceptConnection_ShutdownRequest_ReturnsShutdownResponse()
{
// Arrange
var stream = new TestableStream();
await ServerRequest.CreateShutdown().WriteAsync(stream.ReadStream, CancellationToken.None);
stream.ReadStream.Position = 0;
var connection = CreateConnection(stream);
var connectionHost = CreateConnectionHost();
var compilerHost = CreateCompilerHost();
var dispatcher = new DefaultRequestDispatcher(connectionHost, compilerHost, CancellationToken.None);
// Act
var connectionResult = await dispatcher.AcceptConnection(
Task.FromResult <Connection>(connection), accept : true, cancellationToken : CancellationToken.None);
// Assert
Assert.Equal(ConnectionResult.Reason.ClientShutdownRequest, connectionResult.CloseReason);
stream.WriteStream.Position = 0;
var response = await ServerResponse.ReadAsync(stream.WriteStream).ConfigureAwait(false);
Assert.Equal(ServerResponse.ResponseType.Shutdown, response.Type);
}
public async Task AcceptConnection_AcceptFalse_RejectsBuildRequest()
{
// Arrange
var stream = new TestableStream();
await EmptyServerRequest.WriteAsync(stream.ReadStream, CancellationToken.None);
stream.ReadStream.Position = 0;
var connection = CreateConnection(stream);
var connectionHost = CreateConnectionHost();
var compilerHost = CreateCompilerHost();
var dispatcher = new DefaultRequestDispatcher(connectionHost, compilerHost, CancellationToken.None);
// Act
var connectionResult = await dispatcher.AcceptConnection(
Task.FromResult <Connection>(connection), accept : false, cancellationToken : CancellationToken.None);
// Assert
Assert.Equal(ConnectionResult.Reason.CompilationNotStarted, connectionResult.CloseReason);
stream.WriteStream.Position = 0;
var response = await ServerResponse.ReadAsync(stream.WriteStream).ConfigureAwait(false);
Assert.Equal(ServerResponse.ResponseType.Rejected, response.Type);
}
public async Task ServerRunning_CancelCompilation_CancelsSuccessfully()
{
// Arrange
const int requestCount = 5;
var count = 0;
var completionSource = new TaskCompletionSource <bool>();
var host = CreateCompilerHost(c => c.ExecuteFunc = (req, ct) =>
{
if (Interlocked.Increment(ref count) == requestCount)
{
completionSource.SetResult(true);
}
ct.WaitHandle.WaitOne();
return(new RejectedServerResponse());
});
var semaphore = new SemaphoreSlim(1);
Action <object, EventArgs> onListening = (s, e) =>
{
semaphore.Release();
};
using (var serverData = ServerUtilities.CreateServer(compilerHost: host, onListening: onListening))
{
// Send all the requests.
var clients = new List <Client>();
for (var i = 0; i < requestCount; i++)
{
// Wait for the server to start listening.
await semaphore.WaitAsync(TimeSpan.FromMinutes(1));
var client = await Client.ConnectAsync(serverData.PipeName, timeout : null, cancellationToken : default);
await EmptyServerRequest.WriteAsync(client.Stream);
clients.Add(client);
}
// Act
// Wait until all of the connections are being processed by the server.
await completionSource.Task;
// Now cancel
var stats = await serverData.CancelAndCompleteAsync();
// Assert
Assert.Equal(requestCount, stats.Connections);
Assert.Equal(requestCount, count);
// Read the server response to each client.
foreach (var client in clients)
{
var task = ServerResponse.ReadAsync(client.Stream);
// We expect this to throw because the stream is already closed.
await Assert.ThrowsAnyAsync <IOException>(() => task);
client.Dispose();
}
}
}
