Password Masking

In some cases, it's useful to offer the ability for a user to "mask" their password, or provide it separately from the command line in order to prevent the password from appearing in console history or screenshots. This feature can be enabled on NamedArguments by annotating the property with a PromptValueIfMissingAttribute. You may also, optionally, choose to mask the password (so nothing shows on the screen when you type) or not. If the password is provided in the command line arguments, the value will used without prompting. If missing, the console will prompt for the missing input. Additionally, a SignalString can be provided to explicitly indicate that a value should be prompted. This resolves ambiguity in cases where a positional argument/verb could be mistaken for a value. Defaults to a dash -.

public class Options
{
    [PromptIfValueMissing(MaskInput = true)]
    [NamedArgument('s', "secret")]
    public string SecretValue { get; set; }
}

var opt = CliParser.Parse<Options>(new[] {"-s"});

public class OptionsWithPositional
{
    [PromptIfValueMissing(MaskInput = true)]
    [NamedArgument('s', "secret")]
    public string SecretValue { get; set; }

	[PositionalArgument(0)]
	public string Name { get; set; }
}

var opt = CliParser.Parse<OptionsWithPositional>(new[] {"-s - Nemec"});

Prints:

Input a value for -s:

This feature only applies in a specific set of circumstances:

• Can only annotate a NamedArgument (not a PositionalArgument).
• The ParseAction must be ParseAction.Store (the default).