Custom Tasks

In order to create custom tasks that can be run with mix, you must create a .ex file with the following format:

defmodule Mix.Tasks.MyTaskName do
    use Mix.Task

    @shortdoc "This is my short documentation"
    def run(_) do
        ...
    end
end

The file can be put anywhere, but typically you should put custom task files into /lib/mix/tasks.

The important parts are as follows:

defmodule Mix.Tasks.MyTaskName Including Mix.Tasks in the module means that mix will include the file when looking for tasks.

MyTaskName is the name you will use to run the task. In this case, to run the task you would use the command mix myTaskName

use Mix.Task This directive provides task functionality to the module.

@shortdoc "..." If you include this annotation then your task will be displayed when mix help is called, with the text used as a summary of the task. If you do not include the annotation, your task will not be listed but will still be usable.

def run(args) do ... end This is the code which is run when the task is called. args is the list of arguments passed in from the command line.