policy-node: use default-nodes-api plugin

modules/module-default-nodes-api.c

@@ -82,6 +82,8 @@ on_metadata_changed (WpMetadata *m, guint32 subject,
       self->defaults[node_t] = g_strdup (name);
     }
 
+    wp_debug_object (m, "changed '%s' -> '%s'", key, self->defaults[node_t]);
+
     schedule_changed_notification (self);
   }
 }

modules/module-default-nodes.c

@@ -192,6 +192,9 @@ on_metadata_changed (WpMetadata *m, guint32 subject,
       self->defaults[node_t].config_value = g_strdup (name);
     }
 
+    wp_debug_object (m, "changed '%s' -> '%s'", key,
+        self->defaults[node_t].config_value);
+
     /* re-evaluate the default, taking into account the new configured default;
        block recursive calls to this handler as an optimization */
     g_signal_handlers_block_by_func (m, on_metadata_changed, d);

modules/module-lua-scripting/api.lua

@@ -69,6 +69,11 @@ local function Constraint (spec)
   return debug.setmetatable(spec, { __name = "Constraint" })
 end
 
+local Id = {
+  INVALID = 0xffffffff,
+  ANY = 0xffffffff,
+}
+
 local Features = {
   PipewireObject = {
     MINIMAL = 0x11,
@@ -111,6 +116,7 @@ local Feature = {
 }
 
 SANDBOX_EXPORT = {
+  Id = Id,
   Features = Features,
   Feature = Feature,
   Log = WpDebug,

src/config/config.lua

@@ -60,3 +60,6 @@ load_module("metadata")
 
 -- Enables saving and restoring default nodes
 load_module("default-nodes")
+
+-- API to access default nodes from scripts
+load_module("default-nodes-api")

src/scripts/policy-node.lua

@@ -9,12 +9,6 @@ target_class_assoc = {
   ["Stream/Input/Audio"] = "Audio/Source",
   ["Stream/Output/Audio"] = "Audio/Sink",
   ["Stream/Input/Video"] = "Video/Source",
-  ["Stream/Output/Video"] = "Video/Sink",
-}
-
-default_audio_node_key = {
-  ["Audio/Sink"] = "default.configured.audio.sink",
-  ["Audio/Source"] = "default.configured.audio.source",
 }
 
 function createLink (si, si_target)
@@ -44,6 +38,10 @@ function createLink (si, si_target)
     end
   end
 
+  Log.info (string.format("link %s <-> %s",
+      node.properties["node.name"],
+      target_node.properties["node.name"]))
+
   -- create and configure link
   local si_link = SessionItem ( "si-standard-link" )
   if not si_link:configure {
@@ -80,21 +78,17 @@ function findTarget (node, target_media_class)
 
   -- try to find the best target
   if target == nil then
-    local metadata = metadatas_om:lookup()
+    local def_id = default_nodes:call("get-default-node", target_media_class)
 
     for candidate_si in siportinfos_om:iterate() do
       local n = candidate_si:get_associated_proxy ("node")
       if n and n.properties["media.class"] == target_media_class then
         -- honor default node, if present
-        if metadata then
+        local n_id = n["bound-id"]
-          local key = default_audio_node_key[target_media_class]
+        if def_id ~= Id.INVALID and n_id == def_id then
-          local value = metadata:find(0, key)
+          target = candidate_si
-          local n_id = n["bound-id"]
+          Log.debug (node, "choosing default node " .. n_id)
-          if value and n_id == tonumber(value) then
+          break
-            target = candidate_si
-            Log.debug (node, "choosing default node " .. n_id)
-            break
-          end
         end
 
         -- otherwise just use this candidate
@@ -164,7 +158,7 @@ function reevaulateSiLinks ()
   end
 end
 
-metadatas_om = ObjectManager { Interest { type = "metadata" } }
+default_nodes = Plugin("default-nodes-api")
 siportinfos_om = ObjectManager { Interest { type = "SiPortInfo" } }
 silinks_om = ObjectManager { Interest { type = "SiLink" } }
 
@@ -173,6 +167,5 @@ siportinfos_om:connect("objects-changed", function (om)
   reevaulateSiLinks ()
 end)
 
-metadatas_om:activate()
 siportinfos_om:activate()
 silinks_om:activate()