/// <summary>
/// Runs the application with specified command line arguments and environment variables, and returns the exit code.
/// </summary>
/// <remarks>
/// If a <see cref="CommandException"/> is thrown during command execution, it will be handled and routed to the console.
/// Additionally, if the debugger is not attached (i.e. the app is running in production), all other exceptions thrown within
/// this method will be handled and routed to the console as well.
/// </remarks>
public async ValueTask <int> RunAsync(
IReadOnlyList <string> commandLineArguments,
IReadOnlyDictionary <string, string> environmentVariables)
{
try
{
var root = RootSchema.Resolve(_configuration.CommandTypes);
var input = CommandInput.Parse(commandLineArguments, root.GetCommandNames());
// Debug mode
if (_configuration.IsDebugModeAllowed && input.IsDebugDirectiveSpecified)
{
await LaunchAndWaitForDebuggerAsync();
}
// Preview mode
if (_configuration.IsPreviewModeAllowed && input.IsPreviewDirectiveSpecified)
{
WriteCommandLineInput(input);
return(ExitCode.Success);
}
// Try to get the command matching the input or fallback to default
var command =
root.TryFindCommand(input.CommandName) ??
root.TryFindDefaultCommand() ??
StubDefaultCommand.Schema;
// Version option
if (command.IsVersionOptionAvailable && input.IsVersionOptionSpecified)
{
_console.Output.WriteLine(_metadata.VersionText);
return(ExitCode.Success);
}
// Get command instance (also used in help text)
var instance = GetCommandInstance(command);
// To avoid instantiating the command twice, we need to get default values
// before the arguments are bound to the properties
var defaultValues = command.GetArgumentValues(instance);
// Help option
if (command.IsHelpOptionAvailable && input.IsHelpOptionSpecified ||
command == StubDefaultCommand.Schema && !input.Parameters.Any() && !input.Options.Any())
{
_helpTextWriter.Write(root, command, defaultValues);
return(ExitCode.Success);
}
// Bind arguments
try
{
command.Bind(instance, input, environmentVariables);
}
// This may throw exceptions which are useful only to the end-user
catch (CliFxException ex)
{
WriteError(ex.ToString());
_helpTextWriter.Write(root, command, defaultValues);
return(ExitCode.FromException(ex));
}
// Execute the command
try
{
await instance.ExecuteAsync(_console);
return(ExitCode.Success);
}
// Swallow command exceptions and route them to the console
catch (CommandException ex)
{
WriteError(ex.ToString());
if (ex.ShowHelp)
{
_helpTextWriter.Write(root, command, defaultValues);
}
return(ex.ExitCode);
}
}
// To prevent the app from showing the annoying Windows troubleshooting dialog,
// we handle all exceptions and route them to the console nicely.
// However, we don't want to swallow unhandled exceptions when the debugger is attached,
// because we still want the IDE to show them to the developer.
catch (Exception ex) when(!Debugger.IsAttached)
{
WriteError(ex.ToString());
return(ExitCode.FromException(ex));
}
}
