CliWrap

CliWrap is a library that makes it easier to interact with command line interfaces. It provides a convenient wrapper around the target executable, allowing you to pass execution parameters and read the resulting output. The library can also handle errors reported by the underlying process, allows command cancellation and has both synchronous and asynchronous APIs.

Download

• NuGet: Install-Package CliWrap
• Continuous integration

Features

• Full abstraction over System.Diagnostics.Process
• Execute commands in a synchronous, asynchronous, fire-and-forget manner
• Pass in command line arguments, standard input and environment variables
• Get process exit code, standard output and standard error as the result
• Abort the execution early using System.Threading.CancellationToken
• Set up callbacks that trigger when a process writes to standard output or error
• Custom encoding settings for standard input, output and error
• Fluent interface
• Targets .NET Framework 4.5+, .NET Core 1.0+ and .NET Standard 2.0+
• No external dependencies

Usage

Execute a command

var result = await Cli.Wrap("cli.exe")
    .SetArguments("Hello world!")
    .ExecuteAsync();

var exitCode = result.ExitCode;
var stdOut = result.StandardOutput;
var stdErr = result.StandardError;
var startTime = result.StartTime;
var exitTime = result.ExitTime;
var runTime = result.RunTime;

Standard input

var result = await Cli.Wrap("cli.exe")
    .SetStandardInput("Hello world from stdin!") // can also pipe a stream instead
    .ExecuteAsync();

Environment variables

var result = await Cli.Wrap("cli.exe")
    .SetEnvironmentVariable("var1", "value1")
    .SetEnvironmentVariable("var2", "value2")
    .ExecuteAsync();

Cancel execution

using (var cts = new CancellationTokenSource())
{
    cts.CancelAfter(TimeSpan.FromSeconds(5)); // e.g. timeout of 5 seconds
    
    var result = await Cli.Wrap("cli.exe")
        .SetCancellationToken(cts.Token)
        .ExecuteAsync();
}

Callbacks for stdout and stderr

var result = await Cli.Wrap("cli.exe")
    .SetStandardOutputCallback(l => Console.WriteLine($"StdOut> {l}")) // triggered on every line in stdout
    .SetStandardErrorCallback(l => Console.WriteLine($"StdErr> {l}")) // triggered on every line in stderr
    .ExecuteAsync();

Error handling

var result = await Cli.Wrap("cli.exe")
    .EnableExitCodeValidation(true) // throw exception on non-zero exit code (on by default)
    .EnableStandardErrorValidation(true) // throw exception on non-empty stderr (off by default)
    .ExecuteAsync();

Libraries used

• NUnit