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

2 files changed, 22 insertions, 4 deletions

diff --git a/res/ari/resource_events.c b/res/ari/resource_events.c
index 09bcafc2d..71d54b494 100644
--- a/res/ari/resource_events.c
+++ b/res/ari/resource_events.c
@@ -148,9 +148,11 @@ static void app_handler(void *data, const char *app_name,
  * \brief Register for all of the apps given.
  * \param session Session info struct.
  * \param app_name Name of application to register.
+ * \param register_handler Pointer to the application registration handler
  */
 static int session_register_app(struct event_session *session,
-				 const char *app_name)
+				 const char *app_name,
+				 int (* register_handler)(const char *, stasis_app_cb handler, void *data))
 {
 	SCOPED_AO2LOCK(lock, session);
 
@@ -167,7 +169,7 @@ static int session_register_app(struct event_session *session,
 		return -1;
 	}
 
-	stasis_app_register(app_name, app_handler, session);
+	register_handler(app_name, app_handler, session);
 
 	return 0;
 }
@@ -178,6 +180,7 @@ int ast_ari_websocket_events_event_websocket_attempted(struct ast_tcptls_session
 {
 	int res = 0;
 	size_t i, j;
+	int (* register_handler)(const char *, stasis_app_cb handler, void *data);
 
 	ast_debug(3, "/events WebSocket attempted\n");
 
@@ -186,13 +189,19 @@ int ast_ari_websocket_events_event_websocket_attempted(struct ast_tcptls_session
 		return -1;
 	}
 
+	if (args->subscribe_all) {
+		register_handler = &stasis_app_register_all;
+	} else {
+		register_handler = &stasis_app_register;
+	}
+
 	for (i = 0; i < args->app_count; ++i) {
 		if (ast_strlen_zero(args->app[i])) {
 			res = -1;
 			break;
 		}
 
-		res |= stasis_app_register(args->app[i], app_handler, NULL);
+		res |= register_handler(args->app[i], app_handler, NULL);
 	}
 
 	if (res) {
@@ -213,6 +222,7 @@ void ast_ari_websocket_events_event_websocket_established(struct ast_ari_websock
 	struct ast_json *msg;
 	int res;
 	size_t i;
+	int (* register_handler)(const char *, stasis_app_cb handler, void *data);
 
 	ast_debug(3, "/events WebSocket connection\n");
 
@@ -222,12 +232,18 @@ void ast_ari_websocket_events_event_websocket_established(struct ast_ari_websock
 		return;
 	}
 
+	if (args->subscribe_all) {
+		register_handler = &stasis_app_register_all;
+	} else {
+		register_handler = &stasis_app_register;
+	}
+
 	res = 0;
 	for (i = 0; i < args->app_count; ++i) {
 		if (ast_strlen_zero(args->app[i])) {
 			continue;
 		}
-		res |= session_register_app(session, args->app[i]);
+		res |= session_register_app(session, args->app[i], register_handler);
 	}
 
 	if (ao2_container_count(session->websocket_apps) == 0) {
diff --git a/res/ari/resource_events.h b/res/ari/resource_events.h
index 2b631819b..c48269958 100644
--- a/res/ari/resource_events.h
+++ b/res/ari/resource_events.h
@@ -47,6 +47,8 @@ struct ast_ari_events_event_websocket_args {
 	size_t app_count;
 	/*! Parsing context for app. */
 	char *app_parse;
+	/*! Subscribe to all Asterisk events. If provided, the applications listed will be subscribed to all events, effectively disabling the application specific subscriptions. Default is 'false'. */
+	int subscribe_all;
 };
 
 /*!