Cake.ArgumentHelpers/README.md

Cake.ArgumentHelpers

Cake aliases (methods) to help with consuming arguments and environment variables.

Getting Started

Just reference the Cake.ArgumentHelpers NuGet package directly in your build script via a Cake addin directive.

#addin nuget:?package=Cake.ArgumentHelpers

Available Aliases

Yep, just two so far...

ArgumentOrEnvironmentVariable (for boolean values)

bool ArgumentOrEnvironmentVariable(..., string name, string environmentNamePrefix, bool defaultValue)

Since EnvironmentVariable always returns a string, it is more complex to involve it in an Argument call with a fallback. This alias makes it a single call, hiding away the string comparison done to massage the result to a bool value.

It works by getting a boolean value with multiple fallbacks:

1. Try to get it from Argument (e.g., command line: -SomeSetting="true")
2. Try to get it from EnvironmentVariable (e.g., $env:SomeProject_SomeSetting = $True;)
3. Use a defaultValue if we don't find it elsewhere

Example

Given a potential command line argument of SomeSetting that could also be set via an environment variable prefixed with a project name, get the boolean value or false if it isn't found:

var isSomethingTrue = ArgumentOrEnvironmentVariable("SomeSetting", "SomeProject_", false);

ArgumentOrEnvironmentVariable (for string values)

string ArgumentOrEnvironmentVariable(..., string name, string environmentNamePrefix[, string defaultValue])

This is a helper method that simply wraps around nested calls to Arugment and EnvironmentVariable (and offering a fallback default).

It works by getting a string value with multiple fallbacks:

1. Try to get it from Argument (e.g., command line: -SomeSetting="SomeValue")
2. Try to get it from EnvironmentVariable (e.g., $env:SomeProject_SomeSetting = "SomeOtherValue";)
3. Use a defaultValue if we don't find it elsewhere

Example

Given a potential command line argument of SomeSetting that could also be set via an environment variable prefixed with a project name, get the boolean value or false if it isn't found:

var someVariableValue = ArgumentOrEnvironmentVariable("SomeSetting", "SomeProject_", "SomeFallbackValue");