This module defines the behaviour for custom transformations.

Transformations can be defined inline, in which case this behaviour need not be used, but if you want to define reusable transforms which you can reference in your schema, you should implement this behaviour, and then import the application in your schema so that they are made available by the module name.

Example

[ mappings: [...],
  transforms: [
    "lager.handlers.lager_file_backend": MyApp.Transforms.ToLagerFileBackend,
    "lager.handlers.lager_console_backend": MyApp.Transforms.ToLagerConsoleBackend,
    "lager.handlers": fn conf ->
        file_handlers = Conform.Conf.get(conf, "lager.handlers.lager_file_backend.$level")
          |> Enum.map(fn {[_, _, backend, level], path} -> {backend, [level: level, path: path]} end)
        console_handlers = Conform.Conf.get(conf, "lager.handlers.lager_console_backend")
          |> Enum.map(fn {[_, _, backend], conf} -> {backend, conf}
        console_handlers ++ file_handlers
    end
  ]]

In the case of the two transforms which reference a transform module, the transform/1 function on each will be called with the current configuration state, which is actually a PID of an ETS table. Use the Conform.Conf module to query values from the configuration as shown in the example above.