ARI: Add the ability to subscribe to all events

This patch adds the ability to subscribe to all events. There are two possible
ways to accomplish this:
(1) On initial WebSocket connection. This patch adds a new query parameter,
    'subscribeAll'. If present and True, Asterisk will subscribe the
    applications to all ARI events.
(2) Via the applications resource. When subscribing in this manner, an ARI
    client should merely specify a blank resource name, i.e., 'channels:'
    instead of 'channels:12354'. This will subscribe the application to all
    resources of the 'channels' type.

ASTERISK-24870 #close

Change-Id: I4a943b4db24442cf28bc64b24bfd541249790ad6

1 files changed, 32 insertions, 9 deletions

diff --git a/res/res_stasis.c b/res/res_stasis.c
index f7d8299f4..69e9b935d 100644
--- a/res/res_stasis.c
+++ b/res/res_stasis.c
@@ -109,6 +109,11 @@ struct ao2_container *app_bridges_moh;
 
 struct ao2_container *app_bridges_playback;
 
+/*!
+ * \internal \brief List of registered event sources.
+ */
+AST_RWLIST_HEAD_STATIC(event_sources, stasis_app_event_source);
+
 static struct ast_json *stasis_end_to_json(struct stasis_message *message,
 		const struct stasis_message_sanitizer *sanitize)
 {
@@ -1469,7 +1474,7 @@ struct ao2_container *stasis_app_get_all(void)
 	return ao2_bump(apps);
 }
 
-int stasis_app_register(const char *app_name, stasis_app_cb handler, void *data)
+static int __stasis_app_register(const char *app_name, stasis_app_cb handler, void *data, int all_events)
 {
 	RAII_VAR(struct stasis_app *, app, NULL, ao2_cleanup);
 
@@ -1482,8 +1487,20 @@ int stasis_app_register(const char *app_name, stasis_app_cb handler, void *data)
 	if (app) {
 		app_update(app, handler, data);
 	} else {
-		app = app_create(app_name, handler, data);
+		app = app_create(app_name, handler, data, all_events ? STASIS_APP_SUBSCRIBE_ALL : STASIS_APP_SUBSCRIBE_MANUAL);
 		if (app) {
+			if (all_events) {
+				struct stasis_app_event_source *source;
+				SCOPED_LOCK(lock, &event_sources, AST_RWLIST_RDLOCK, AST_RWLIST_UNLOCK);
+
+				AST_LIST_TRAVERSE(&event_sources, source, next) {
+					if (!source->subscribe) {
+						continue;
+					}
+
+					source->subscribe(app, NULL);
+				}
+			}
 			ao2_link_flags(apps_registry, app, OBJ_NOLOCK);
 		} else {
 			ao2_unlock(apps_registry);
@@ -1499,6 +1516,16 @@ int stasis_app_register(const char *app_name, stasis_app_cb handler, void *data)
 	return 0;
 }
 
+int stasis_app_register(const char *app_name, stasis_app_cb handler, void *data)
+{
+	return __stasis_app_register(app_name, handler, data, 0);
+}
+
+int stasis_app_register_all(const char *app_name, stasis_app_cb handler, void *data)
+{
+	return __stasis_app_register(app_name, handler, data, 1);
+}
+
 void stasis_app_unregister(const char *app_name)
 {
 	RAII_VAR(struct stasis_app *, app, NULL, ao2_cleanup);
@@ -1526,11 +1553,6 @@ void stasis_app_unregister(const char *app_name)
 	cleanup();
 }
 
-/*!
- * \internal \brief List of registered event sources.
- */
-AST_RWLIST_HEAD_STATIC(event_sources, stasis_app_event_source);
-
 void stasis_app_register_event_source(struct stasis_app_event_source *obj)
 {
 	SCOPED_LOCK(lock, &event_sources, AST_RWLIST_WRLOCK, AST_RWLIST_UNLOCK);
@@ -1727,8 +1749,8 @@ static enum stasis_app_subscribe_res app_subscribe(
 
 	ast_debug(3, "%s: Checking %s\n", app_name, uri);
 
-	if (!event_source->find ||
-	    (!(obj = event_source->find(app, uri + strlen(event_source->scheme))))) {
+	if (!ast_strlen_zero(uri + strlen(event_source->scheme)) &&
+	    (!event_source->find || (!(obj = event_source->find(app, uri + strlen(event_source->scheme)))))) {
 		ast_log(LOG_WARNING, "Event source not found: %s\n", uri);
 		return STASIS_ASR_EVENT_SOURCE_NOT_FOUND;
 	}
@@ -2062,6 +2084,7 @@ static int load_module(void)
 }
 
 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS, "Stasis application support",
+	.load_pri = AST_MODPRI_APP_DEPEND,
 	.support_level = AST_MODULE_SUPPORT_CORE,
 	.load = load_module,
 	.unload = unload_module,