Simplify call an external process with the async streams in C# 8.0.
ProcessX simplifies call an external process with the aync streams in C# 8.0 without complex
Processcode. You can receive standard output results by
await foreach, it is completely asynchronous and realtime.
Install library from NuGet that support from
.NET Standard 2.0.
PM> Install-Package ProcessX
Main API is only
Cysharp.Diagnostics.ProcessX.StartAsyncand throws
ProcessErrorExceptionwhen error detected.
using Cysharp.Diagnostics; // using namespace// async iterate. await foreach (string item in ProcessX.StartAsync("dotnet --info")) { Console.WriteLine(item); }
// receive buffered result(similar as WaitForExit). string[] result = await ProcessX.StartAsync("dotnet --info").ToTask();
// like the shell exec, write all data to console. await ProcessX.StartAsync("dotnet --info").WriteLineAllAsync();
// when ExitCode is not 0 or StandardError is exists, throws ProcessErrorException try { await foreach (var item in ProcessX.StartAsync("dotnet --foo --bar")) { } } catch (ProcessErrorException ex) { // int .ExitCode // string[] .ErrorOutput Console.WriteLine(ex.ToString()); }
to Cancel, you can use
WithCancellationof IAsyncEnumerable.
// when cancel has been called and process still exists, call process kill before exit. await foreach (var item in ProcessX.StartAsync("dotnet --info").WithCancellation(cancellationToken)) { Console.WriteLine(item); }
timeout, you can use
CancellationTokenSource(delay).
using (var cts = new CancellationTokenSource(TimeSpan.FromSeconds(1))) { await foreach (var item in ProcessX.StartAsync("dotnet --info").WithCancellation(cts.Token)) { Console.WriteLine(item); } }
In default, when stdError is used, buffering error messages and throws
ProcessErrorExceptionwith error messages after process exited. If you want to use stdError in streaming or avoid throws error when process using stderror as progress, diagnostics, you can use
GetDualAsyncEnumerablemethod. Also
GetDualAsyncEnumerablecan get raw
Process, you can use
ProcessID,
StandardInputetc.
// first argument is Process, if you want to know ProcessID, use StandardInput, use it. var (_, stdOut, stdError) = ProcessX.GetDualAsyncEnumerable("dotnet --foo --bar");var consumeStdOut = Task.Run(async () => { await foreach (var item in stdOut) { Console.WriteLine("STDOUT: " + item); } });
var errorBuffered = new List(); var consumeStdError = Task.Run(async () => { await foreach (var item in stdError) { Console.WriteLine("STDERROR: " + item); errorBuffered.Add(item); } });
try { await Task.WhenAll(consumeStdOut, consumeStdError); } catch (ProcessErrorException ex) { // stdout iterator throws exception when exitcode is not 0. Console.WriteLine("ERROR, ExitCode: " + ex.ExitCode);
// ex.ErrorOutput is empty, if you want to use it, buffer yourself. // Console.WriteLine(string.Join(Environment.NewLine, errorBuffered));
}
If stdout is binary data, you can use
StartReadBinaryAsyncto read
byte[].
byte[] bin = await ProcessX.StartReadBinaryAsync($"...");
In default, ExitCode is not 0 throws ProcessErrorException. You can change acceptable exit codes globally by
ProcessX.AcceptableExitCodesproperty. Default is
[0].
ProcessX.StartAsyncoverloads, you can set workingDirectory, environmentVariable, encoding.
// return ProcessAsyncEnumerable StartAsync(string command, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) StartAsync(string fileName, string? arguments, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) StartAsync(ProcessStartInfo processStartInfo)// return (Process, ProcessAsyncEnumerable, ProcessAsyncEnumerable) GetDualAsyncEnumerable(string command, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) GetDualAsyncEnumerable(string fileName, string? arguments, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) GetDualAsyncEnumerable(ProcessStartInfo processStartInfo)
// return Task StartReadBinaryAsync(string command, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) StartReadBinaryAsync(string fileName, string? arguments, string? workingDirectory = null, IDictionary? environmentVariable = null, Encoding? encoding = null) StartReadBinaryAsync(ProcessStartInfo processStartInfo)
// return Task ToTask(CancellationToken cancellationToken = default)
// return Task WriteLineAllAsync(CancellationToken cancellationToken = default)
This library is under the MIT License.