Stopt calling handle_spec_started in between handling actions

lib/membrane/core/bin/action_handler.ex

@@ -6,6 +6,7 @@ defmodule Membrane.Core.Bin.ActionHandler do
   alias Membrane.Core
   alias Membrane.Core.Bin.State
   alias Membrane.Core.{Message, Parent, TimerController}
+  alias Membrane.Core.Parent.ChildLifeController
 
   require Membrane.Logger
   require Message
@@ -34,7 +35,14 @@ defmodule Membrane.Core.Bin.ActionHandler do
   end
 
   @impl CallbackHandler
-  def handle_action({:spec, spec}, _cb, _params, state) do
+  def handle_action({:spec, spec}, cb, _params, state) do
+    if cb == :handle_spec_started do
+      Membrane.Logger.warning("""
+      Action :spec was returned from handle_spec_started/3 callback. It is suggested not to do this,
+      because it might lead to infinite loof of handle_spec_started/3 executions.
+      """)
+    end
+
     Parent.ChildLifeController.handle_spec(spec, state)
   end
 
@@ -108,4 +116,9 @@ defmodule Membrane.Core.Bin.ActionHandler do
   def handle_action(action, _callback, _params, _state) do
     raise ActionError, action: action, reason: {:unknown_action, Membrane.Bin.Action}
   end
+
+  @impl CallbackHandler
+  def handle_end_of_actions(state) do
+    ChildLifeController.trigger_specs(state)
+  end
 end

lib/membrane/core/bin/state.ex

@@ -40,6 +40,7 @@ defmodule Membrane.Core.Bin.State do
           },
           children_log_metadata: Keyword.t(),
           pending_specs: ChildLifeController.pending_specs(),
+          specs_to_trigger: [ChildLifeController.spec_ref()],
           playback: Membrane.Playback.t(),
           initialized?: boolean(),
           terminating?: boolean(),
@@ -69,6 +70,7 @@ defmodule Membrane.Core.Bin.State do
             links: %{},
             crash_groups: %{},
             pending_specs: %{},
+            specs_to_trigger: [],
             synchronization: nil,
             initialized?: false,
             terminating?: false,

lib/membrane/core/parent/child_life_controller.ex

@@ -71,6 +71,12 @@ defmodule Membrane.Core.Parent.ChildLifeController do
     log_metadata: []
   }
 
+  # todo: handle documentation
+  @spec handle_spec(ChildrenSpec.t(), Parent.state()) :: Parent.state()
+  def handle_spec(spec, state) do
+    Map.update!(state, :specs_to_trigger, &[spec | &1])
+  end
+
   @doc """
   Handles `Membrane.ChildrenSpec` returned with `spec` action.
 
@@ -99,8 +105,16 @@ defmodule Membrane.Core.Parent.ChildLifeController do
   - Cleanup spec: remove it from `pending_specs` and all other specs' `dependent_specs` and try proceeding startup
     for all other pending specs that depended on the spec.
   """
-  @spec handle_spec(ChildrenSpec.t(), Parent.state()) :: Parent.state() | no_return()
-  def handle_spec(spec, state) do
+  @spec trigger_specs(Parent.state()) :: Parent.state() | no_return()
+  def trigger_specs(state) do
+    specs_to_trigger = state.specs_to_trigger
+    state = %{state | specs_to_trigger: []}
+
+    List.foldr(specs_to_trigger, state, &do_trigger_spec/2)
+  end
+
+  @spec do_trigger_spec(ChildrenSpec.t(), Parent.state()) :: Parent.state() | no_return()
+  defp do_trigger_spec(spec, state) do
     spec_ref = make_ref()
     canonical_spec = make_canonical(spec)
 

lib/membrane/core/pipeline/action_handler.ex

@@ -5,9 +5,11 @@ defmodule Membrane.Core.Pipeline.ActionHandler do
   alias Membrane.ActionError
   alias Membrane.Core
   alias Membrane.Core.{Parent, TimerController}
-  alias Membrane.Core.Parent.LifecycleController
+  alias Membrane.Core.Parent.{ChildLifeController, LifecycleController}
   alias Membrane.Core.Pipeline.State
 
+  require Membrane.Logger
+
   @impl CallbackHandler
   def handle_action({:spec, args}, _cb, _params, %State{terminating?: true}) do
     raise Membrane.ParentError,
@@ -32,7 +34,14 @@ defmodule Membrane.Core.Pipeline.ActionHandler do
   end
 
   @impl CallbackHandler
-  def handle_action({:spec, spec}, _cb, _params, state) do
+  def handle_action({:spec, spec}, cb, _params, state) do
+    if cb == :handle_spec_started do
+      Membrane.Logger.warning("""
+      Action :spec was returned from handle_spec_started/3 callback. It is suggested not to do this,
+      because it might lead to infinite loof of handle_spec_started/3 executions.
+      """)
+    end
+
     Parent.ChildLifeController.handle_spec(spec, state)
   end
 
@@ -105,11 +114,11 @@ defmodule Membrane.Core.Pipeline.ActionHandler do
   end
 
   @impl CallbackHandler
-  def handle_end_of_actions(state) when state.awaiting_setup_completition? do
-    %{state | awaiting_setup_completition?: false}
-    |> Membrane.Core.LifecycleController.complete_setup()
+  def handle_end_of_actions(state) do
+    with %{awaiting_setup_completition?: true} <- state do
+      %{state | awaiting_setup_completition?: false}
+      |> Membrane.Core.LifecycleController.complete_setup()
+    end
+    |> ChildLifeController.trigger_specs()
   end
-
-  @impl CallbackHandler
-  def handle_end_of_actions(state), do: state
 end

lib/membrane/core/pipeline/state.ex

@@ -20,6 +20,7 @@ defmodule Membrane.Core.Pipeline.State do
           links: %{Link.id() => Link.t()},
           crash_groups: %{CrashGroup.name() => CrashGroup.t()},
           pending_specs: ChildLifeController.pending_specs(),
+          specs_to_trigger: [ChildLifeController.spec_ref()],
           synchronization: %{
             timers: %{Timer.id() => Timer.t()},
             clock_provider: %{
@@ -52,6 +53,7 @@ defmodule Membrane.Core.Pipeline.State do
             links: %{},
             crash_groups: %{},
             pending_specs: %{},
+            specs_to_trigger: [],
             synchronization: nil,
             initialized?: false,
             terminating?: false,

test/membrane/core/pipeline_test.exs

@@ -79,6 +79,7 @@ defmodule Membrane.Core.PipelineTest do
           [],
           state
         )
+        |> ActionHandler.handle_end_of_actions()
       end
     end
 
@@ -92,6 +93,7 @@ defmodule Membrane.Core.PipelineTest do
           [],
           state
         )
+        |> ActionHandler.handle_end_of_actions()
       end
     end
   end