Membrane.Testing.Source (Membrane Core v0.7.0) View Source

Testing Element for supplying data based on generator function or payloads passed through options.

Example usage

As mentioned earlier you can use this element in one of two ways, providing either a generator function or an Enumerable.t.

If you provide an Enumerable.t with payloads, then each of those payloads will be wrapped in a Membrane.Buffer and sent through :output pad.

%Source{output: [0xA1, 0xB2, 0xC3, 0xD4]}

In order to specify Membrane.Testing.Source with generator function you need to provide initial state and function that matches generator/0 type. This function should take state and demand size as its arguments and return a tuple consisting of actions that element will return during the Membrane.Element.WithOutputPads.handle_demand/5 callback and new state.

generator_function = fn state, size ->
  #generate some buffers
  {actions, state + 1}
end
%Source{output: {1, generator_function}}

Element options

Passed via struct Membrane.Testing.Source.t/0

  • output

    {initial_state :: any(), generator} | Enum.t()

    Default value: {0, &Membrane.Testing.Source.default_buf_gen/2}
    If output is an enumerable with Membrane.Payload.t() then buffer containing those payloads will be sent through the :output pad and followed by Membrane.Element.Action.end_of_stream_t/0. If output is a {initial_state, function} tuple then the the function will be invoked each time handle_demand is called. It is an action generator that takes two arguments. The first argument is the state that is initially set to initial_state. The second one defines the size of the demand. Such function should return {actions, next_state} where actions is a list of actions that will be returned from handle_demand/4 and next_state is the value that will be used for the next call.

  • caps

    struct()

    Default value: %Membrane.RemoteStream{content_format: nil, type: :bytestream}
    Caps to be sent before the output.

Pads

:output

Availability:always
Caps:any
Direction:output
Mode:pull
Name:output

Link to this section Summary

Types

t()

Struct containing options for Membrane.Testing.Source

Functions

Returns pads descriptions for Membrane.Testing.Source

Returns description of options available for this module

Creates output with generator function from list of buffers.

Link to this section Types

Specs

generator() ::
  (state :: any(), buffers_cnt :: pos_integer() ->
     {[Membrane.Element.Action.t()], state :: any()})

Specs

t() :: %Membrane.Testing.Source{
  caps: struct(),
  output: {initial_state :: any(), generator()} | Enum.t()
}

Struct containing options for Membrane.Testing.Source

Link to this section Functions

Link to this function

default_buf_gen(generator_state, size)

View Source

Specs

default_buf_gen(integer(), integer()) ::
  {[Membrane.Element.Action.t()], integer()}

Specs

membrane_pads() :: [{Membrane.Pad.name_t(), Membrane.Pad.description_t()}]

Returns pads descriptions for Membrane.Testing.Source

Specs

options() :: keyword()

Returns description of options available for this module

Link to this function

output_from_buffers(data)

View Source

Specs

output_from_buffers([Membrane.Buffer.t()]) ::
  {[Membrane.Buffer.t()], generator()}

Creates output with generator function from list of buffers.