Membrane Core v0.5.0 Membrane.Pipeline behaviour View Source

Module containing functions for constructing and supervising pipelines.

Pipelines are units that make it possible to instantiate, link and manage elements and bins in convenient way (actually they should always be used inside a pipeline). Linking pipeline children together enables them to pass data to one another, and process it in different ways.

To create a pipeline, use the __using__/1 macro and implement callbacks of Membrane.Pipeline behaviour. For details on instantiating and linking children, see Membrane.ParentSpec.

Link to this section Summary

Types

pipeline_options_t()

Defines options that can be passed to start/3 / start_link/3 and received in handle_init/1 callback.

Functions

__using__(options)

Brings all the stuff necessary to implement a pipeline.

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

pipeline?(module)

Checks whether module is a pipeline.

play(pid)

Changes playback state to :playing.

prepare(pid)

Changes playback state to :prepared.

start(module, pipeline_options \\ nil, process_options \\ [])

Does the same as start_link/3 but starts process outside of supervision tree.

start_link(module, pipeline_options \\ nil, process_options \\ [])

Starts the Pipeline based on given module and links it to the current process.

stop(pid)

Changes playback state to :stopped.

stop_and_terminate(pipeline)

Changes pipeline's playback state to :stopped and terminates its process

Callbacks

handle_init(options)

Callback invoked on initialization of pipeline process. It should parse options and initialize pipeline's internal state. Internally it is invoked inside GenServer.init/1 callback.

handle_shutdown(reason, state)

Callback invoked when pipeline is shutting down. Internally called in GenServer.terminate/2 callback.

membrane_pipeline?()

Enables to check whether module is membrane pipeline

Link to this section Types

pipeline_options_t()

pipeline_options_t() :: any()

Defines options that can be passed to start/3 / start_link/3 and received in handle_init/1 callback.

Link to this section Functions

using(options)

(macro)

Brings all the stuff necessary to implement a pipeline.

Options:

:bring_spec? - if true (default) imports and aliases Membrane.ParentSpec
:bring_pad? - if true (default) requires and aliases Membrane.Pad

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

See Supervisor.

pipeline?(module)

pipeline?(module()) :: boolean()

Checks whether module is a pipeline.

play(pid)

play(pid()) :: :ok

Changes playback state to :playing.

An alias for Membrane.Core.PlaybackHandler.change_playback_state/2 with proper state.

prepare(pid)

prepare(pid()) :: :ok

Changes playback state to :prepared.

An alias for Membrane.Core.PlaybackHandler.change_playback_state/2 with proper state.

start(module, pipeline_options \\ nil, process_options \\ [])

start(
  module(),
  pipeline_options :: pipeline_options_t(),
  process_options :: GenServer.options()
) :: GenServer.on_start()

Does the same as start_link/3 but starts process outside of supervision tree.

start_link(module, pipeline_options \\ nil, process_options \\ [])

start_link(
  module(),
  pipeline_options :: pipeline_options_t(),
  process_options :: GenServer.options()
) :: GenServer.on_start()

Starts the Pipeline based on given module and links it to the current process.

Pipeline options are passed to module's handle_init/1 callback.

Process options are internally passed to GenServer.start_link/3.

Returns the same values as GenServer.start_link/3.

stop(pid)

stop(pid()) :: :ok

Changes playback state to :stopped.

An alias for Membrane.Core.PlaybackHandler.change_playback_state/2 with proper state.

stop_and_terminate(pipeline)

stop_and_terminate(pipeline :: pid()) :: :ok

Changes pipeline's playback state to :stopped and terminates its process

Link to this section Callbacks

handle_init(options)

handle_init(options :: pipeline_options_t()) ::
  Membrane.Core.CallbackHandler.callback_return_t()

Callback invoked on initialization of pipeline process. It should parse options and initialize pipeline's internal state. Internally it is invoked inside GenServer.init/1 callback.

handle_shutdown(reason, state)

handle_shutdown(
  reason,
  state :: Membrane.Core.Pipeline.State.internal_state_t()
) :: :ok
when reason: :normal | :shutdown | {:shutdown, any()}

Callback invoked when pipeline is shutting down. Internally called in GenServer.terminate/2 callback.

Useful for any cleanup required.

membrane_pipeline?()

membrane_pipeline?() :: true

Enables to check whether module is membrane pipeline