protected override void ProcessRecord() { // iterate attempting to connect, send and receive to Chef node server. for (int tryIndex = 0; tryIndex < Constants.MAX_CLIENT_RETRIES; ++tryIndex) { ITransport transport = new JsonTransport(); PipeClient pipeClient = new PipeClient(PipeName, transport); try { // FIX: query the current value of $LastExitCode from powershell host. int lastExitCode = 0; GetNextActionRequest request = new GetNextActionRequest(lastExitCode); pipeClient.Connect(Constants.NEXT_ACTION_CONNECT_TIMEOUT_MSECS); IDictionary responseHash = (IDictionary)transport.NormalizeDeserializedObject(pipeClient.SendReceive<object>(request)); if (null == responseHash) { if (tryIndex + 1 < Constants.MAX_CLIENT_RETRIES) { // delay retry a few ticks to yield time in case server is busy. Thread.Sleep(Constants.SLEEP_BETWEEN_CLIENT_RETRIES_MSECS); continue; } else { string message = String.Format("Failed to get expected response after {0} retries.", Constants.MAX_CLIENT_RETRIES); throw new GetNextActionException(message); } } if (ChefNodeCmdletExceptionBase.HasError(responseHash)) { throw new GetNextActionException(responseHash); } // can't write a null object to pipeline, so write nothing in the null case. string nextAction = responseHash.Contains(Constants.JSON_NEXT_ACTION_KEY) ? responseHash[Constants.JSON_NEXT_ACTION_KEY].ToString() : null; if (null == nextAction) { throw new GetNextActionException("Received null for next action; expecting an exit command when finished."); } // automagically convert next action into an invocable script block. // // example of use: // // while ($TRUE) // { // $Error.clear() // $nextAction = $NULL // $nextAction = get-NextAction // if ($Error.Count -eq 0) // { // write-output $nextAction // Invoke-Command -scriptblock $nextAction // sleep 1 // } // else // { // break // } // } ScriptBlock scriptBlock = ScriptBlock.Create(nextAction); WriteObject(scriptBlock); // done. break; } catch (TimeoutException e) { ThrowTerminatingError(new ErrorRecord(e, "Connection timed out", ErrorCategory.OperationTimeout, pipeClient)); } catch (GetNextActionException e) { ThrowTerminatingError(new ErrorRecord(e, "get-NextAction exception", ErrorCategory.InvalidResult, pipeClient)); } catch (Exception e) { ThrowTerminatingError(new ErrorRecord(e, "Unexpected exception", ErrorCategory.NotSpecified, pipeClient)); } finally { pipeClient.Close(); pipeClient = null; } } }
protected override void ProcessRecord() { // iterate attempting to connect, send and receive to Chef node server. for (int tryIndex = 0; tryIndex < Constants.MAX_CLIENT_RETRIES; ++tryIndex) { ITransport transport = new JsonTransport(); PipeClient pipeClient = new PipeClient(PipeName, transport); try { GetNextActionRequest request = new GetNextActionRequest(LastActionExitCode, LastActionErrorMessage); pipeClient.Connect(Constants.NEXT_ACTION_CONNECT_TIMEOUT_MSECS); IDictionary responseHash = (IDictionary)transport.NormalizeDeserializedObject(pipeClient.SendReceive <object>(request)); if (null == responseHash) { if (tryIndex + 1 < Constants.MAX_CLIENT_RETRIES) { // delay retry a few ticks to yield time in case server is busy. Thread.Sleep(Constants.SLEEP_BETWEEN_CLIENT_RETRIES_MSECS); continue; } else { string message = String.Format("Failed to get expected response after {0} retries.", Constants.MAX_CLIENT_RETRIES); throw new GetNextActionException(message); } } if (ChefNodeCmdletExceptionBase.HasError(responseHash)) { throw new GetNextActionException(responseHash); } // next action cannot be null. string nextAction = responseHash.Contains(Constants.JSON_NEXT_ACTION_KEY) ? responseHash[Constants.JSON_NEXT_ACTION_KEY].ToString() : null; if (null == nextAction) { throw new GetNextActionException("Received null for next action; expecting an exit command when finished."); } // enhance next action with try-catch logic to set the $global:RS_LastErrorRecord variable // in case of an exception thrown by a script. the try-catch block loses details of script // execution if caught by an outer block instead of the inner block which threw it. nextAction = NEXT_ACTION_PREFIX + nextAction + NEXT_ACTION_POSTFIX; // automagically convert next action into an invocable script block. // // example of use: // // while ($TRUE) // { // $Error.clear() // $nextAction = $NULL // $nextAction = get-NextAction $pipeName // if ($Error.Count -eq 0) // { // write-output $nextAction // Invoke-Command -scriptblock $nextAction // sleep 1 // } // else // { // break // } // } ScriptBlock scriptBlock = ScriptBlock.Create(nextAction); WriteObject(scriptBlock); // done. break; } catch (TimeoutException e) { ThrowTerminatingError(new ErrorRecord(e, "Connection timed out", ErrorCategory.OperationTimeout, pipeClient)); } catch (GetNextActionException e) { ThrowTerminatingError(new ErrorRecord(e, "get-NextAction exception", ErrorCategory.InvalidResult, pipeClient)); } catch (Exception e) { ThrowTerminatingError(new ErrorRecord(e, "Unexpected exception", ErrorCategory.NotSpecified, pipeClient)); } finally { pipeClient.Close(); pipeClient = null; } } }
static void Main(string[] args) { // resolve persistent node path. string pipeName = null; string nextActionPath = null; if (4 == args.Length && args[0] == "-pn" && args[2] == "-na") { pipeName = args[1]; nextActionPath = args[3]; } else { Console.WriteLine("Usage: -pn <pipe name> -na <next action file path>"); Console.WriteLine(); Console.WriteLine("The <pipe name> is any legal file name which uniquely distinguishes the pipe server."); Console.WriteLine("The <next action file path> is a text file containing a list of actions to execute in PowerShell."); return; } FileStream fileStream = null; StreamReader streamReader = null; try { // read next action file linewise. fileStream = new FileStream(nextActionPath, FileMode.OpenOrCreate, FileAccess.Read); streamReader = new StreamReader(fileStream); // use JSON transport to unmarshal initial nodes. ITransport transport = new JsonTransport(); // create pipe server using JSON as transport. PipeServer pipeServer = new PipeServer(pipeName, transport); Console.WriteLine("Hit Ctrl+C to stop the server."); bool moreCommands = true; while (moreCommands) { try { Console.WriteLine("Waiting for client to connect..."); pipeServer.WaitForConnection(); GetNextActionRequest request = pipeServer.Receive <GetNextActionRequest>(); if (null == request) { break; } Console.WriteLine(String.Format("Received: {0}", request.ToString())); for (;;) { string nextLine = streamReader.ReadLine(); if (null == nextLine) { moreCommands = false; nextLine = "exit"; } if (nextLine.Trim().Length > 0) { GetNextActionResponse response = new GetNextActionResponse(nextLine); Console.WriteLine(String.Format("Responding: {0}", response.ToString())); pipeServer.Send(response); break; } } } catch (Exception e) { Console.WriteLine(e.Message); } finally { pipeServer.Close(); } } } catch (IOException e) { Console.WriteLine(e.Message); } finally { if (null != streamReader) { streamReader.Close(); streamReader = null; } if (null != fileStream) { fileStream.Close(); fileStream = null; } } }