Expose live application audio groups

config/dot/quickshell/audio-streams-harness.qml

@@ -1,8 +1,10 @@
 import Quickshell
 import Quickshell.Io
+import Quickshell.Services.Pipewire
 import QtQuick
 
 import "services/AudioStreams.js" as AudioStreams
+import qs.services
 
 ShellRoot {
     readonly property int audioOutStreamFlag: 4
@@ -112,5 +114,23 @@ ShellRoot {
                 muted: chromium.nodes.map(node => node.audio.muted)
             });
         }
+
+        function serviceSummary(): string {
+            const applications = AudioDevices.applications;
+            return JSON.stringify({
+                count: applications.length,
+                validTypes: applications.every(application =>
+                    application.nodes.every(node =>
+                        (node.type & PwNodeType.AudioOutStream)
+                            === PwNodeType.AudioOutStream))
+            });
+        }
+
+        function invalidMutations(): string {
+            return JSON.stringify({
+                nullVolume: AudioDevices.setApplicationVolume(null, 0.5),
+                emptyMute: AudioDevices.setApplicationMuted({ nodes: [] }, true)
+            });
+        }
     }
 }

config/dot/quickshell/services/AudioDevices.qml

@@ -8,6 +8,8 @@ import Quickshell
 import Quickshell.Services.Pipewire
 import QtQuick
 
+import "AudioStreams.js" as AudioStreams
+
 Singleton {
     id: root
 
@@ -18,6 +20,13 @@ Singleton {
         !node.isStream
         && (node.type & PwNodeType.AudioSource) === PwNodeType.AudioSource)
 
+    readonly property var playbackStreams: Pipewire.nodes.values.filter(node =>
+        node.ready && node.audio
+        && (node.type & PwNodeType.AudioOutStream) === PwNodeType.AudioOutStream)
+
+    readonly property var applications: AudioStreams.group(
+        root.playbackStreams, PwNodeType.AudioOutStream)
+
     function nodes(output: bool): var {
         return output ? root.outputs : root.inputs;
     }
@@ -40,4 +49,20 @@ Singleton {
             return "Unknown device";
         return node.description || node.nickname || node.name || "Unknown device";
     }
+
+    function applicationVolume(application: var): real {
+        return AudioStreams.volume(application);
+    }
+
+    function applicationMuted(application: var): bool {
+        return AudioStreams.muted(application);
+    }
+
+    function setApplicationVolume(application: var, value: real): bool {
+        return AudioStreams.setVolume(application, value);
+    }
+
+    function setApplicationMuted(application: var, muted: bool): bool {
+        return AudioStreams.setMuted(application, muted);
+    }
 }

tests/quickshell/application-volume-contract.sh

@@ -77,6 +77,14 @@ mute_result="$(qs_for_harness ipc call application-volume-test mutateMute)"
 jq -e '.changed == true and .muted == [true, true]' <<<"$mute_result" >/dev/null \
     || fail "mute mutation did not reach every stream: $mute_result"
 
+service_summary="$(qs_for_harness ipc call application-volume-test serviceSummary)"
+jq -e '.count >= 0 and .validTypes == true' <<<"$service_summary" >/dev/null \
+    || fail "live service exposed invalid playback groups: $service_summary"
+
+invalid_result="$(qs_for_harness ipc call application-volume-test invalidMutations)"
+jq -e '.nullVolume == false and .emptyMute == false' <<<"$invalid_result" >/dev/null \
+    || fail "service mutators accepted missing audio nodes: $invalid_result"
+
 if rg -n 'ReferenceError|TypeError|Binding loop|Cannot assign|PwObjectTracker' "$shell_log"; then
     fail 'isolated harness emitted a QML runtime error'
 fi