@spec default_handler(map()) :: {:ok, String.t()}

Default handler function used when no handler is specified.

@spec execute(
  map(),
  {module(), atom()}
) :: {:ok, any()} | {:error, map()}

Executes the handler function with the given payload. Handles proper error conversion and response formatting.

@spec resolve() :: {module(), atom()}

Resolves the handler module and function from environment variables. Returns a tuple with {module, function}.

Examples

iex> System.put_env("_HANDLER", "Elixir.MyModule.my_function")
iex> Mayfly.Handler.resolve()
{MyModule, :my_function}