feat(playout): configure device for alsa and pulseaudio system outputs (#2654)

### Description

Add hardware configuration to liquidsoap so that users may
set hardware output in config.yml.

---------

Co-authored-by: jo <ljonas@riseup.net>

docker/config.template.yml

@@ -326,3 +326,7 @@ stream:
         # > must be one of (alsa, ao, oss, portaudio, pulseaudio)
         # > default is pulseaudio
         kind: pulseaudio
+
+        # System output device.
+        # > only available for kind=(alsa, pulseaudio)
+        device:

docker/config.yml

@@ -326,3 +326,7 @@ stream:
         # > must be one of (alsa, ao, oss, portaudio, pulseaudio)
         # > default is pulseaudio
         kind: pulseaudio
+
+        # System output device.
+        # > only available for kind=(alsa, pulseaudio)
+        device:

docker/example/config.yml

@@ -326,3 +326,7 @@ stream:
         # > must be one of (alsa, ao, oss, portaudio, pulseaudio)
         # > default is pulseaudio
         kind: pulseaudio
+
+        # System output device.
+        # > only available for kind=(alsa, pulseaudio)
+        device:

docs/admin-manual/configuration.md

@@ -526,11 +526,15 @@ stream:
     system:
       - # Whether the output is enabled.
         # > default is false
-        enabled: false
+        enabled: true
         # System output kind.
         # > must be one of (alsa, ao, oss, portaudio, pulseaudio)
         # > default is pulseaudio
         kind: "pulseaudio"
+
+        # System output device.
+        # > only available for kind=(alsa, pulseaudio)
+        device: "alsa_output.pci-0000_00_1f.3-platform-skl_hda_dsp_generic.HiFi__hw_sofhdadsp__sink"
 ```
 
 ## LDAP

installer/config.yml

@@ -326,3 +326,7 @@ stream:
         # > must be one of (alsa, ao, oss, portaudio, pulseaudio)
         # > default is pulseaudio
         kind: pulseaudio
+
+        # System output device.
+        # > only available for kind=(alsa, pulseaudio)
+        device:

legacy/application/configs/conf.php

@@ -211,6 +211,7 @@ class Schema implements ConfigurationInterface
             /*    */->validate()->ifNotInArray(["alsa", "ao", "oss", "portaudio", "pulseaudio"])
             /*    */->thenInvalid('invalid stream.outputs.system.kind %s')
             /*  */->end()->end()
+            /*  */->scalarNode('device')->end()
             /**/->end()->end()->end()
 
             ->end()->end()

playout/libretime_playout/liquidsoap/templates/outputs.liq.j2

@@ -117,20 +117,41 @@ output.shoutcast(
 )
 {%- endmacro -%}
 
-{% for output in config.stream.outputs.system -%}
-{% if output.enabled -%}
-# {{ output.kind.value }}:{{ loop.index }}
+{#-
+  Build a system output configuration.
+#}
+{%- macro output_system(output_id, output) -%}
+# {{ output.kind.value }}:{{ output_id }}
 %ifndef output.{{ output.kind.value }}
 log("output.{{ output.kind.value }} is not defined!")
 %endif
 %ifdef output.{{ output.kind.value }}
-output.{{ output.kind.value }}(id="{{ output.kind.value }}:{{ loop.index }}", s)
+output.{{ output.kind.value }}(
+  id="{{ output.kind.value }}:{{ output_id }}",
+{%- if output.kind.value == "alsa" %}
+{%- if output.device is not none %}
+  device="{{ output.device }}",
+{%- endif %}
+{%- elif output.kind.value == "pulseaudio" %}
+{%- if output.device is not none %}
+  device="{{ output.device }}",
+{%- endif %}
+{%- endif %}
+  s
+)
 %endif
+{%- endmacro -%}
+
+{# ############################### #}
+
+{%- for output in config.stream.outputs.system -%}
+{% if output.enabled -%}
+{{ output_system(loop.index, output) }}
 
 {% endif -%}
 {% endfor -%}
 
-{% for output in config.stream.outputs.icecast -%}
+{%- for output in config.stream.outputs.icecast -%}
 {% if output.enabled -%}
 {{ output_icecast(loop.index, output) }}
 

playout/tests/liquidsoap/__snapshots__/entrypoint_test.ambr

@@ -315,7 +315,10 @@
   log("output.pulseaudio is not defined!")
   %endif
   %ifdef output.pulseaudio
-  output.pulseaudio(id="pulseaudio:1", s)
+  output.pulseaudio(
+    id="pulseaudio:1",
+    s
+  )
   %endif
   
   
@@ -355,6 +358,55 @@
   
   %include "/fake/1.4/ls_script.liq"
   
+  # pulseaudio:1
+  %ifndef output.pulseaudio
+  log("output.pulseaudio is not defined!")
+  %endif
+  %ifdef output.pulseaudio
+  output.pulseaudio(
+    id="pulseaudio:1",
+    device="alsa_output.pci-0000_00_sink",
+    s
+  )
+  %endif
+  
+  
+  
+  gateway("started")
+  
+  '''
+# ---
+# name: test_generate_entrypoint[stream_config7-1.4]
+  '''
+  # THIS FILE IS AUTO GENERATED. PLEASE DO NOT EDIT!
+  ###########################################################
+  # The ignore() lines are to squash unused variable warnings
+  
+  # Inputs
+  input_main_mount = "main"
+  input_main_port = 8001
+  input_main_secure = false
+  input_show_mount = "show"
+  input_show_port = 8002
+  input_show_secure = false
+  
+  # Settings
+  set("log.file.path", "/var/log/radio.log")
+  
+  set("server.telnet", true)
+  set("server.telnet.bind_addr", "127.0.0.1")
+  set("server.telnet.port", 1234)
+  
+  set("harbor.bind_addrs", ["0.0.0.0"])
+  
+  station_name = interactive.string("station_name", "LibreTime")
+  
+  message_offline = interactive.string("message_offline", "LibreTime - offline")
+  message_format = interactive.string("message_format", "0")
+  input_fade_transition = interactive.float("input_fade_transition", 0.0)
+  
+  %include "/fake/1.4/ls_script.liq"
+  
   
   
   gateway("started")

playout/tests/liquidsoap/fixtures/__init__.py

@@ -92,6 +92,17 @@ TEST_STREAM_CONFIGS: List[Config] = [
             "system": [{"enabled": True, "kind": "pulseaudio"}],
         }
     ),
+    make_config_with_stream(
+        outputs={
+            "system": [
+                {
+                    "enabled": True,
+                    "kind": "pulseaudio",
+                    "device": "alsa_output.pci-0000_00_sink",
+                }
+            ],
+        }
+    ),
     make_config_with_stream(
         outputs={
             "system": [{"enabled": False, "kind": "alsa"}],

shared/libretime_shared/config/_models.py

@@ -216,7 +216,7 @@ class ShoutcastOutput(BaseModel):
     mobile: bool = False
 
 
-class SystemOutputKind(str, Enum):
+class SystemOutput(str, Enum):
     ALSA = "alsa"
     AO = "ao"
     OSS = "oss"
@@ -224,16 +224,49 @@ class SystemOutputKind(str, Enum):
     PULSEAUDIO = "pulseaudio"
 
 
-class SystemOutput(BaseModel):
+class BaseSystemOutput(BaseModel):
     enabled: bool = False
-    kind: SystemOutputKind = SystemOutputKind.PULSEAUDIO
+
+
+class ALSASystemOutput(BaseSystemOutput):
+    kind: Literal[SystemOutput.ALSA] = SystemOutput.ALSA
+    device: Optional[str] = None
+
+
+class AOSystemOutput(BaseSystemOutput):
+    kind: Literal[SystemOutput.AO] = SystemOutput.AO
+
+
+class OSSSystemOutput(BaseSystemOutput):
+    kind: Literal[SystemOutput.OSS] = SystemOutput.OSS
+
+
+class PortAudioSystemOutput(BaseSystemOutput):
+    kind: Literal[SystemOutput.PORTAUDIO] = SystemOutput.PORTAUDIO
+
+
+class PulseAudioSystemOutput(BaseSystemOutput):
+    kind: Literal[SystemOutput.PULSEAUDIO] = SystemOutput.PULSEAUDIO
+    device: Optional[str] = None
+
+
+AnySystemOutput = Annotated[
+    Union[
+        ALSASystemOutput,
+        AOSystemOutput,
+        OSSSystemOutput,
+        PortAudioSystemOutput,
+        PulseAudioSystemOutput,
+    ],
+    Field(discriminator="kind", default=SystemOutput.PULSEAUDIO),
+]
 
 
 # pylint: disable=too-few-public-methods
 class Outputs(BaseModel):
     icecast: List[IcecastOutput] = Field([], max_length=3)
     shoutcast: List[ShoutcastOutput] = Field([], max_length=1)
-    system: List[SystemOutput] = Field([], max_length=1)
+    system: List[AnySystemOutput] = Field([], max_length=1)
 
     @property
     def merged(self) -> List[Union[IcecastOutput, ShoutcastOutput]]: