lua: change the Conf API to have methods for getting sections as specific types

In some cases we need to get a section as JSON, so that we can pass it
down to the rules parser, while in other cases we neeed to get it as a
table to use it natively, and in that case we even need to differentiate
between it being an object, an array or an object with WpProperties.

Make it also possible to optionally pass tables with default values to
the functions so that we can get rid of cutils.get_config_section()
as well.

modules/module-lua-scripting/api/api.c

@@ -1619,37 +1619,103 @@ impl_module_new (lua_State *L)
 /* WpConf */
 
 static int
-conf_get_section (lua_State *L)
+conf_get_section_as_properties (lua_State *L)
 {
+  const char *section = luaL_checkstring (L, 1);
+  g_autoptr (WpConf) conf = wp_core_get_conf (get_wp_core (L));
+  g_autoptr (WpSpaJson) s = NULL;
+  g_autoptr (WpProperties) props = NULL;
+
+  if (lua_istable (L, 2))
+    props = wplua_table_to_properties (L, 2);
+  else
+    props = wp_properties_new_empty ();
+
+  if (conf) {
+    s = wp_conf_get_section (conf, section);
+    if (s && wp_spa_json_is_object (s))
+      wp_properties_update_from_json (props, s);
+  }
+  wplua_properties_to_table (L, props);
+  return 1;
+}
+
+static int
+conf_get_section_as_object (lua_State *L)
+{
+  const char *section = luaL_checkstring (L, 1);
   g_autoptr (WpConf) conf = wp_core_get_conf (get_wp_core (L));
-  const char *section;
-  g_autoptr (WpSpaJson) fb = NULL;
   g_autoptr (WpSpaJson) s = NULL;
 
-  if (!conf) {
-    lua_pushnil (L);
-    return 1;
+  if (conf) {
+    s = wp_conf_get_section (conf, section);
+    if (s && wp_spa_json_is_object (s)) {
+      push_luajson (L, s, INT_MAX);
+      return 1;
+    }
   }
 
-  section = luaL_checkstring (L, 1);
-  if (lua_isuserdata (L, 2)) {
-    WpSpaJson *v = wplua_checkboxed (L, 2, WP_TYPE_SPA_JSON);
-    if (v)
-      fb = wp_spa_json_ref (v);
-  }
-
-  s = wp_conf_get_section (conf, section);
-  if (s)
-    wplua_pushboxed (L, WP_TYPE_SPA_JSON, g_steal_pointer (&s));
-  else if (fb)
-    wplua_pushboxed (L, WP_TYPE_SPA_JSON, g_steal_pointer (&fb));
+  if (lua_istable (L, 2))
+    lua_pushvalue (L, 2);
   else
-    lua_pushnil (L);
+    lua_newtable (L);
+  return 1;
+}
+
+static int
+conf_get_section_as_array (lua_State *L)
+{
+  const char *section = luaL_checkstring (L, 1);
+  g_autoptr (WpConf) conf = wp_core_get_conf (get_wp_core (L));
+  g_autoptr (WpSpaJson) s = NULL;
+
+  if (conf) {
+    s = wp_conf_get_section (conf, section);
+    if (s && wp_spa_json_is_array (s)) {
+      push_luajson (L, s, INT_MAX);
+      return 1;
+    }
+  }
+
+  if (lua_istable (L, 2))
+    lua_pushvalue (L, 2);
+  else
+    lua_newtable (L);
+  return 1;
+}
+
+static int
+conf_get_section_as_json (lua_State *L)
+{
+  const char *section = luaL_checkstring (L, 1);
+  g_autoptr (WpConf) conf = NULL;
+  g_autoptr (WpSpaJson) s = NULL;
+  WpSpaJson *fb = NULL;
+
+  if (lua_isuserdata (L, 2))
+    fb = wplua_checkboxed (L, 2, WP_TYPE_SPA_JSON);
+
+  conf = wp_core_get_conf (get_wp_core (L));
+  if (conf) {
+    s = wp_conf_get_section (conf, section);
+    if (!s && fb)
+      s = wp_spa_json_ref (fb);
+    if (s) {
+      wplua_pushboxed (L, WP_TYPE_SPA_JSON,
+          wp_spa_json_ensure_unique_owner (g_steal_pointer (&s)));
+      return 1;
+    }
+  }
+
+  lua_pushnil (L);
   return 1;
 }
 
 static const luaL_Reg conf_methods[] = {
-  { "get_section", conf_get_section },
+  { "get_section_as_properties", conf_get_section_as_properties },
+  { "get_section_as_object", conf_get_section_as_object },
+  { "get_section_as_array", conf_get_section_as_array },
+  { "get_section_as_json", conf_get_section_as_json },
   { NULL, NULL }
 };
 

src/scripts/client/access-default.lua

@@ -43,7 +43,7 @@ function getDefaultPermissions (properties)
 end
 
 function getPermissions (properties)
-  local section = Conf.get_section ("access.rules")
+  local section = Conf.get_section_as_json ("access.rules")
   if section then
     local matched, mprops = JsonUtils.match_rules_update_properties (
         section, properties)

src/scripts/lib/common-utils.lua

@@ -84,7 +84,7 @@ function cutils.get_default_metadata_object ()
 end
 
 function cutils.evaluateRulesApplyProperties (properties, name)
-  local section = Conf.get_section (name)
+  local section = Conf.get_section_as_json (name)
   if not section then
     return
   end
@@ -112,26 +112,4 @@ function cutils.get_application_name ()
   return Core.get_properties()["application.name"] or "WirePlumber"
 end
 
-function cutils.get_config_section (name, defaults)
-  local section = Conf.get_section (name)
-  if not section then
-    section = defaults or {}
-  else
-    section = section:parse ()
-    if defaults then
-      for k, v in pairs (defaults) do
-        if section [k] == nil then
-          section [k] = v
-        end
-      end
-      for k, v in ipairs (defaults) do
-        if section [k] == nil then
-          section [k] = v
-        end
-      end
-    end
-  end
-  return section
-end
-
 return cutils

src/scripts/linking/find-virtual-target.lua

@@ -9,12 +9,8 @@
 lutils = require ("linking-utils")
 log = Log.open_topic ("s-linking")
 
-defaults = {}
-defaults.roles = Json.Object {}
-
 config = {}
-config.roles = Conf.get_section (
-    "virtual-item-roles", defaults.roles):parse ()
+config.roles = Conf.get_section_as_object ("virtual-item-roles")
 
 function findRole(role, tmc)
   if role and not config.roles[role] then

src/scripts/linking/rescan-virtual-links.lua

@@ -10,13 +10,10 @@ log = Log.open_topic ("s-linking")
 
 defaults = {}
 defaults.duck_level = 0.3
-defaults.roles = Json.Object {}
 
 config = {}
-config.duck_level = Conf.get_value_float ("wireplumber.settings",
-    "linking.default.duck-level", defaults.duck_level)
-config.roles = Conf.get_section (
-    "virtual-item-roles", defaults.roles):parse ()
+config.duck_level = default.duck_level -- FIXME
+config.roles = Conf.get_section_as_object ("virtual-item-roles")
 
 -- enable ducking if mixer-api is loaded
 mixer_api = Plugin.find("mixer-api")

src/scripts/monitors/alsa-midi.lua

@@ -8,9 +8,22 @@
 cutils = require ("common-utils")
 log = Log.open_topic ("s-monitors")
 
+defaults = {}
+defaults.node_properties = {  -- Midi bridge node properties
+  ["factory.name"] = "api.alsa.seq.bridge",
+
+  -- Name set for the node with ALSA MIDI ports
+  ["node.name"] = "Midi-Bridge",
+
+  -- Set priorities so that it can be used as a fallback driver (see pipewire#3562)
+  ["priority.session"] = "100",
+  ["priority.driver"] = "1",
+}
+
 config = {}
 config.monitoring = Core.test_feature ("monitor.alsa-midi.monitoring")
-config.node_properties = cutils.get_config_section ("monitor.alsa-midi.properties")
+config.node_properties = Conf.get_section_as_properties (
+    "monitor.alsa-midi.properties", defaults.node_properties)
 
 SND_PATH = "/dev/snd"
 SEQ_NAME = "seq"
@@ -20,23 +33,8 @@ midi_node = nil
 fm_plugin = nil
 
 function CreateMidiNode ()
-  -- Midi properties
-  local props = {
-    ["factory.name"] = "api.alsa.seq.bridge",
-
-    -- Name set for the node with ALSA MIDI ports
-    ["node.name"] = "Midi-Bridge",
-
-    -- Set priorities so that it can be used as a fallback driver (see pipewire#3562)
-    ["priority.session"] = "100",
-    ["priority.driver"] = "1",
-  }
-  for k, v in pairs(config.node_properties) do
-    props[k] = v
-  end
-
   -- create the midi node
-  local node = Node("spa-node-factory", props)
+  local node = Node("spa-node-factory", config.node_properties)
   node:activate(Feature.Proxy.BOUND, function (n)
     log:info ("activated Midi bridge")
   end)

src/scripts/monitors/alsa.lua

@@ -10,7 +10,7 @@ log = Log.open_topic ("s-monitors")
 
 config = {}
 config.reserve_device = Core.test_feature ("monitor.alsa.reserve-device")
-config.properties = cutils.get_config_section ("monitor.alsa.properties")
+config.properties = Conf.get_section_as_properties ("monitor.alsa.properties")
 
 -- unique device/node name tables
 device_names_table = nil

src/scripts/monitors/bluez-midi.lua

@@ -13,8 +13,8 @@ defaults.servers = { "bluez_midi.server" }
 
 config = {}
 config.seat_monitoring = Core.test_feature ("monitor.bluez.seat-monitoring")
-config.properties = cutils.get_config_section ("monitor.bluez-midi.properties")
-config.servers = cutils.get_config_section ("monitor.bluez-midi.servers", defaults.servers)
+config.properties = Conf.get_section_as_properties ("monitor.bluez-midi.properties")
+config.servers = Conf.get_section_as_array ("monitor.bluez-midi.servers", defaults.servers)
 
 -- unique device/node name tables
 node_names_table = nil

src/scripts/monitors/bluez.lua

@@ -14,7 +14,7 @@ log = Log.open_topic ("s-monitors")
 
 config = {}
 config.seat_monitoring = Core.test_feature ("monitor.bluez.seat-monitoring")
-config.properties = cutils.get_config_section ("monitor.bluez.properties")
+config.properties = Conf.get_section_as_properties ("monitor.bluez.properties")
 
 -- This is not a setting, it must always be enabled
 config.properties["api.bluez5.connection-info"] = true

src/scripts/monitors/libcamera/enumerate-device.lua

@@ -9,7 +9,7 @@ cutils = require ("common-utils")
 log = Log.open_topic ("s-monitors-libcamera")
 
 config = {}
-config.properties = cutils.get_config_section ("monitor.libcamera.properties")
+config.properties = Conf.get_section_as_properties ("monitor.libcamera.properties")
 
 function createCamDevice (parent, id, type, factory, properties)
   source = source or Plugin.find ("standard-event-source")

src/scripts/monitors/v4l2/enumerate-device.lua

@@ -9,7 +9,7 @@ cutils = require ("common-utils")
 log = Log.open_topic ("s-monitors-v4l2")
 
 config = {}
-config.properties = cutils.get_config_section ("monitor.v4l2.properties")
+config.properties = Conf.get_section_as_properties ("monitor.v4l2.properties")
 
 function createCamDevice (parent, id, type, factory, properties)
   source = source or Plugin.find ("standard-event-source")

src/scripts/node/create-virtual-item.lua

@@ -11,12 +11,8 @@
 
 log = Log.open_topic ("s-node")
 
-defaults = {}
-defaults.virtual_items = Json.Object {}
-
 config = {}
-config.virtual_items = Conf.get_section (
-    "virtual-items", defaults.virtual_items):parse ()
+config.virtual_items = Conf.get_section_as_object ("virtual-items")
 
 function createVirtualItem (factory_name, properties)
   -- create virtual item