View Source Igniter.Mix.Task behaviour (igniter v0.5.0)
A behaviour for implementing a Mix task that is enriched to be composable with other Igniter tasks.
Note
A default run/1 is implemented so you can directly run the task. Igniter never uses this function, so it is overridable.
This enables your library to make use of the task for its own purposes if needed. An example would be if you wanted to implement an Igniter installer, but also have an install task for end-user consumption (e.g. mix tailwind.install).
Options and Arguments
Command line args are automatically parsed into igniter.args using the configuration returned
from info/2. See Igniter.Mix.Task.Info for more.
Summary
Callbacks
Main entrypoint for tasks. This callback accepts and returns an Igniter struct.
All the generator behavior happens here, you take an igniter and task arguments, and return an igniter.
Returns an Igniter.Mix.Task.Info struct, with information used when running the igniter task.
Returns an Igniter.Mix.Task.Args struct.
Whether or not it supports being run in the root of an umbrella project
Callbacks
Main entrypoint for tasks. This callback accepts and returns an Igniter struct.
All the generator behavior happens here, you take an igniter and task arguments, and return an igniter.
@callback info(argv :: [String.t()], composing_task :: nil | String.t()) :: Igniter.Mix.Task.Info.t()
Returns an Igniter.Mix.Task.Info struct, with information used when running the igniter task.
This info will be used to validate arguments in composed tasks.
Use the positional_args!(argv) to get your positional arguments according to your info.positional, and the remaining unused args.
Use the options!(argv) macro to get your parsed options according to your info.schema.
Important Limitations
- Each task still must parse its own argv in
igniter/2and must ignore any unknown options. To accomplish this, use the automatically importedoptions!(argv)macro, which uses theinfo/2callback to validate args and return options - You cannot use
composesto list tasks unless they are in your library or in direct dependencies of your library. To validate their options, you must include their options in your own option schema.
@callback installer?() :: boolean()
@callback parse_argv(argv :: [String.t()]) :: Igniter.Mix.Task.Args.t()
Returns an Igniter.Mix.Task.Args struct.
This callback can be implemented to private custom parsing and validation behavior for
command line arguments. By default, the options specified in info/2 will be used
to inject a default implementation.
@callback supports_umbrella?() :: boolean()
Whether or not it supports being run in the root of an umbrella project
At the moment, this is still experimental and we suggest not turning it on.