Add channel events for res_stasis apps

This change adds a framework in res_stasis for handling events from channel topics. JSON event generation and validation code is created from event documentation in rest-api/api-docs/events.json to assist in JSON event generation, ensure consistency, and ensure that accurate documentation is available for ALL events that are received by res_stasis applications. The userevent application has been refactored along with the code that handles userevent channel blob events to pass the headers as key/value pairs in the JSON blob. As a side-effect, app_userevent now handles duplicate keys by overwriting the previous value. Review: https://reviewboard.asterisk.org/r/2428/ (closes issue ASTERISK-21180) Patch-By: Kinsey Moore <kmoore@digium.com> git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@388275 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2025-10-14 08:31:02 +00:00 · 2013-05-10 13:13:06 +00:00
parent 2cfedc12ad
commit 7ce05bfb9b
18 changed files with 1593 additions and 292 deletions
--- a/res/res_stasis.c
+++ b/res/res_stasis.c
@@ -39,6 +39,9 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/stasis_app.h"
 #include "asterisk/stasis_channels.h"
 #include "asterisk/strings.h"
+#include "asterisk/stasis_message_router.h"
+#include "asterisk/callerid.h"
+#include "stasis_http/resource_events.h"

 /*! Time to wait for a frame in the application */
 #define MAX_WAIT_MS 200
@@ -55,6 +58,18 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 */
 #define CONTROLS_NUM_BUCKETS 127

+/*!
+ * \brief Number of buckets for the channels container for app instances.  Remember
+ * to keep it a prime number!
+ */
+#define APP_CHANNELS_BUCKETS 7
+
+/*!
+ * \brief Number of buckets for the blob_handlers container.  Remember to keep
+ * it a prime number!
+ */
+#define BLOB_HANDLER_BUCKETS 7
+
 /*!
 * \brief Stasis application container. Please call apps_registry() instead of
 * directly accessing.
@@ -63,6 +78,9 @@ struct ao2_container *__apps_registry;

 struct ao2_container *__app_controls;

+/*! \brief Message router for the channel caching topic */
+struct stasis_message_router *channel_router;
+
 /*! Ref-counting accessor for the stasis applications container */
 static struct ao2_container *apps_registry(void)
 {
@@ -81,6 +99,8 @@ struct app {
 	stasis_app_cb handler;
 	/*! Opaque data to hand to callback function. */
 	void *data;
+	/*! List of channel identifiers this app instance is interested in */
+	struct ao2_container *channels;
 	/*! Name of the Stasis application */
 	char name[];
 };
@@ -91,12 +111,14 @@ static void app_dtor(void *obj)

 	ao2_cleanup(app->data);
 	app->data = NULL;
+	ao2_cleanup(app->channels);
+	app->channels = NULL;
 }

 /*! Constructor for \ref app. */
 static struct app *app_create(const char *name, stasis_app_cb handler, void *data)
 {
-	struct app *app;
+	RAII_VAR(struct app *, app, NULL, ao2_cleanup);
 	size_t size;

 	ast_assert(name != NULL);
@@ -114,6 +136,12 @@ static struct app *app_create(const char *name, stasis_app_cb handler, void *dat
 	ao2_ref(data, +1);
 	app->data = data;

+	app->channels = ast_str_container_alloc(APP_CHANNELS_BUCKETS);
+	if (!app->channels) {
+		return NULL;
+	}
+
+	ao2_ref(app, +1);
 	return app;
 }

@@ -140,6 +168,27 @@ static int app_compare(void *lhs, void *rhs, int flags)
 	}
 }

+static int app_add_channel(struct app* app, const struct ast_channel *chan)
+{
+	const char *uniqueid;
+	ast_assert(chan != NULL);
+	ast_assert(app != NULL);
+
+	uniqueid = ast_channel_uniqueid(chan);
+	if (!ast_str_container_add(app->channels, uniqueid)) {
+		return -1;
+	}
+	return 0;
+}
+
+static void app_remove_channel(struct app* app, const struct ast_channel *chan)
+{
+	ast_assert(chan != NULL);
+	ast_assert(app != NULL);
+
+	ao2_find(app->channels, ast_channel_uniqueid(chan), OBJ_KEY | OBJ_NODATA | OBJ_UNLINK);
+}
+
 /*!
 * \brief Send a message to the given application.
 * \param app App to send the message to.
@@ -316,6 +365,9 @@ void stasis_app_control_continue(struct stasis_app_control *control)
 	control->continue_to_dialplan = 1;
 }

+/*! \brief Typedef for blob handler callbacks */
+typedef struct ast_json *(*channel_blob_handler_cb)(struct ast_channel_blob *);
+
 static int OK = 0;
 static int FAIL = -1;

@@ -343,43 +395,11 @@ int stasis_app_control_answer(struct stasis_app_control *control)
 	return *retval;
 }

-static struct ast_json *app_event_create(
-	const char *event_name,
-	const struct ast_channel_snapshot *snapshot,
-	const struct ast_json *extra_info)
-{
-	RAII_VAR(struct ast_json *, message, NULL, ast_json_unref);
-	RAII_VAR(struct ast_json *, event, NULL, ast_json_unref);
-
-	if (extra_info) {
-		event = ast_json_deep_copy(extra_info);
-	} else {
-		event = ast_json_object_create();
-	}
-
-	if (snapshot) {
-		int ret;
-
-		/* Mustn't already have a channel field */
-		ast_assert(ast_json_object_get(event, "channel") == NULL);
-
-		ret = ast_json_object_set(
-			event,
-			"channel", ast_channel_snapshot_to_json(snapshot));
-		if (ret != 0) {
-			return NULL;
-		}
-	}
-
-	message = ast_json_pack("{s: o}", event_name, ast_json_ref(event));
-
-	return ast_json_ref(message);
-}
-
 static int send_start_msg(struct app *app, struct ast_channel *chan,
 			  int argc, char *argv[])
 {
 	RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
+	RAII_VAR(struct ast_json *, blob, NULL, ast_json_unref);
 	RAII_VAR(struct ast_channel_snapshot *, snapshot, NULL, ao2_cleanup);

 	struct ast_json *json_args;
@@ -393,19 +413,13 @@ static int send_start_msg(struct app *app, struct ast_channel *chan,
 		return -1;
 	}

-	msg = ast_json_pack("{s: {s: [], s: o}}",
-			    "stasis-start",
-			    "args",
-			    "channel", ast_channel_snapshot_to_json(snapshot));
-
-	if (!msg) {
+	blob = ast_json_pack("{s: []}", "args");
+	if (!blob) {
 		return -1;
 	}

 	/* Append arguments to args array */
-	json_args = ast_json_object_get(
-		ast_json_object_get(msg, "stasis-start"),
-		"args");
+	json_args = ast_json_object_get(blob, "args");
 	ast_assert(json_args != NULL);
 	for (i = 0; i < argc; ++i) {
 		int r = ast_json_array_append(json_args,
@@ -416,6 +430,11 @@ static int send_start_msg(struct app *app, struct ast_channel *chan,
 		}
 	}

+	msg = stasis_json_event_stasis_start_create(snapshot, blob);
+	if (!msg) {
+		return -1;
+	}
+
 	app_send(app, msg);
 	return 0;
 }
@@ -432,7 +451,8 @@ static int send_end_msg(struct app *app, struct ast_channel *chan)
 	if (snapshot == NULL) {
 		return -1;
 	}
-	msg = app_event_create("stasis-end", snapshot, NULL);
+
+	msg = stasis_json_event_stasis_end_create(snapshot);
 	if (!msg) {
 		return -1;
 	}
@@ -441,62 +461,201 @@ static int send_end_msg(struct app *app, struct ast_channel *chan)
 	return 0;
 }

-static void dtmf_handler(struct app *app, struct ast_channel_blob *obj)
+static int app_watching_channel_cb(void *obj, void *arg, int flags)
+{
+	RAII_VAR(char *, uniqueid, NULL, ao2_cleanup);
+	struct app *app = obj;
+	char *chan_uniqueid = arg;
+
+	uniqueid = ao2_find(app->channels, chan_uniqueid, OBJ_KEY);
+	return uniqueid ? CMP_MATCH : 0;
+}
+
+static struct ao2_container *get_watching_apps(const char *uniqueid)
+{
+	RAII_VAR(struct ao2_container *, apps, apps_registry(), ao2_cleanup);
+	struct ao2_container *watching_apps;
+	char *uniqueid_dup;
+	RAII_VAR(struct ao2_iterator *,watching_apps_iter, NULL, ao2_iterator_destroy);
+	ast_assert(uniqueid != NULL);
+	ast_assert(apps != NULL);
+
+	uniqueid_dup = ast_strdupa(uniqueid);
+
+	watching_apps_iter = ao2_callback(apps, OBJ_MULTIPLE, app_watching_channel_cb, uniqueid_dup);
+	watching_apps = watching_apps_iter->c;
+
+	if (!ao2_container_count(watching_apps)) {
+		return NULL;
+	}
+
+	ao2_ref(watching_apps, +1);
+	return watching_apps_iter->c;
+}
+
+/*! \brief Typedef for callbacks that get called on channel snapshot updates */
+typedef struct ast_json *(*channel_snapshot_monitor)(
+	struct ast_channel_snapshot *old_snapshot,
+	struct ast_channel_snapshot *new_snapshot);
+
+/*! \brief Handle channel state changes */
+static struct ast_json *channel_state(
+	struct ast_channel_snapshot *old_snapshot,
+	struct ast_channel_snapshot *new_snapshot)
+{
+	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
+	struct ast_channel_snapshot *snapshot = new_snapshot ? new_snapshot : old_snapshot;
+
+	if (!old_snapshot) {
+		return stasis_json_event_channel_created_create(snapshot);
+	} else if (!new_snapshot) {
+		json = ast_json_pack("{s: i, s: s}",
+			"cause", snapshot->hangupcause,
+			"cause_txt", ast_cause2str(snapshot->hangupcause));
+		if (!json) {
+			return NULL;
+		}
+		return stasis_json_event_channel_destroyed_create(snapshot, json);
+	} else if (old_snapshot->state != new_snapshot->state) {
+		return stasis_json_event_channel_state_change_create(snapshot);
+	}
+
+	return NULL;
+}
+
+static struct ast_json *channel_dialplan(
+	struct ast_channel_snapshot *old_snapshot,
+	struct ast_channel_snapshot *new_snapshot)
+{
+	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
+
+	/* No Newexten event on cache clear */
+	if (!new_snapshot) {
+		return NULL;
+	}
+
+	/* Empty application is not valid for a Newexten event */
+	if (ast_strlen_zero(new_snapshot->appl)) {
+		return NULL;
+	}
+
+	if (old_snapshot && ast_channel_snapshot_cep_equal(old_snapshot, new_snapshot)) {
+		return NULL;
+	}
+
+	json = ast_json_pack("{s: s, s: s}",
+		"application", new_snapshot->appl,
+		"application_data", new_snapshot->data);
+	if (!json) {
+		return NULL;
+	}
+
+	return stasis_json_event_channel_dialplan_create(new_snapshot, json);
+}
+
+static struct ast_json *channel_callerid(
+	struct ast_channel_snapshot *old_snapshot,
+	struct ast_channel_snapshot *new_snapshot)
+{
+	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
+
+	/* No NewCallerid event on cache clear or first event */
+	if (!old_snapshot || !new_snapshot) {
+		return NULL;
+	}
+
+	if (ast_channel_snapshot_caller_id_equal(old_snapshot, new_snapshot)) {
+		return NULL;
+	}
+
+	json = ast_json_pack("{s: i, s: s}",
+		"caller_presentation", new_snapshot->caller_pres,
+		"caller_presentation_txt", ast_describe_caller_presentation(new_snapshot->caller_pres));
+	if (!json) {
+		return NULL;
+	}
+
+	return stasis_json_event_channel_caller_id_create(new_snapshot, json);
+}
+
+static struct ast_json *channel_snapshot(
+	struct ast_channel_snapshot *old_snapshot,
+	struct ast_channel_snapshot *new_snapshot)
+{
+	if (!new_snapshot) {
+		return NULL;
+	}
+
+	return stasis_json_event_channel_snapshot_create(new_snapshot);
+}
+
+channel_snapshot_monitor channel_monitors[] = {
+	channel_snapshot,
+	channel_state,
+	channel_dialplan,
+	channel_callerid
+};
+
+static int app_send_cb(void *obj, void *arg, int flags)
+{
+	struct app *app = obj;
+	struct ast_json *msg = arg;
+
+	app_send(app, msg);
+	return 0;
+}
+
+static void sub_snapshot_handler(void *data,
+		struct stasis_subscription *sub,
+		struct stasis_topic *topic,
+		struct stasis_message *message)
+{
+	RAII_VAR(struct ao2_container *, watching_apps, NULL, ao2_cleanup);
+	struct stasis_cache_update *update = stasis_message_data(message);
+	struct ast_channel_snapshot *new_snapshot = stasis_message_data(update->new_snapshot);
+	struct ast_channel_snapshot *old_snapshot = stasis_message_data(update->old_snapshot);
+	int i;
+
+	watching_apps = get_watching_apps(new_snapshot ? new_snapshot->uniqueid : old_snapshot->uniqueid);
+	if (!watching_apps) {
+		return;
+	}
+
+	for (i = 0; i < ARRAY_LEN(channel_monitors); ++i) {
+		RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
+
+		msg = channel_monitors[i](old_snapshot, new_snapshot);
+		if (msg) {
+			ao2_callback(watching_apps, OBJ_NODATA, app_send_cb, msg);
+		}
+	}
+}
+
+static void distribute_message(struct ao2_container *apps, struct ast_json *msg)
+{
+	ao2_callback(apps, OBJ_NODATA, app_send_cb, msg);
+}
+
+static void generic_blob_handler(struct ast_channel_blob *obj, channel_blob_handler_cb handler_cb)
 {
-	RAII_VAR(struct ast_json *, extra, NULL, ast_json_unref);
 	RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
-	const char *direction;
+	RAII_VAR(struct ao2_container *, watching_apps, NULL, ao2_cleanup);

-	/* To simplify events, we'll only generate on receive */
-	direction = ast_json_string_get(
-		ast_json_object_get(obj->blob, "direction"));
-
-	if (strcmp("Received", direction) != 0) {
+	if (!obj->snapshot) {
 		return;
 	}

-	extra = ast_json_pack(
-		"{s: o}",
-		"digit", ast_json_ref(ast_json_object_get(obj->blob, "digit")));
-	if (!extra) {
+	watching_apps = get_watching_apps(obj->snapshot->uniqueid);
+	if (!watching_apps) {
 		return;
 	}

-	msg = app_event_create("dtmf-received", obj->snapshot, extra);
+	msg = handler_cb(obj);
 	if (!msg) {
 		return;
 	}

-	app_send(app, msg);
-}
-
-static void sub_handler(void *data, struct stasis_subscription *sub,
-			struct stasis_topic *topic,
-			struct stasis_message *message)
-{
-	struct app *app = data;
-
-	if (stasis_subscription_final_message(sub, message)) {
-		ao2_cleanup(data);
-		return;
-	}
-
-	if (ast_channel_snapshot_type() == stasis_message_type(message)) {
-		RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
-		struct ast_channel_snapshot *snapshot =
-			stasis_message_data(message);
-
-		msg = app_event_create("channel-state-change", snapshot, NULL);
-		if (!msg) {
-			return;
-		}
-		app_send(app, msg);
-	} else if (ast_channel_dtmf_end_type() == stasis_message_type(message)) {
-		/* To simplify events, we'll only generate on DTMF end */
-		struct ast_channel_blob *blob = stasis_message_data(message);
-		dtmf_handler(app, blob);
-	}
-
+	distribute_message(watching_apps, msg);
 }

 /*!
@@ -544,8 +703,6 @@ int stasis_app_exec(struct ast_channel *chan, const char *app_name, int argc,
 	RAII_VAR(struct ao2_container *, apps, apps_registry(), ao2_cleanup);
 	RAII_VAR(struct app *, app, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_app_control *, control, NULL, control_unlink);
-	RAII_VAR(struct stasis_subscription *, subscription, NULL,
-		 stasis_unsubscribe);
 	int res = 0;
 	int hungup = 0;

@@ -570,21 +727,17 @@ int stasis_app_exec(struct ast_channel *chan, const char *app_name, int argc,
 		ao2_link(controls, control);
 	}

-	subscription =
-		stasis_subscribe(ast_channel_topic(chan), sub_handler, app);
-	if (subscription == NULL) {
-		ast_log(LOG_ERROR, "Error subscribing app %s to channel %s\n",
-			app_name, ast_channel_name(chan));
-		return -1;
-	}
-	ao2_ref(app, +1); /* subscription now has a reference */
-
 	res = send_start_msg(app, chan, argc, argv);
 	if (res != 0) {
 		ast_log(LOG_ERROR, "Error sending start message to %s\n", app_name);
 		return res;
 	}

+	if (app_add_channel(app, chan)) {
+		ast_log(LOG_ERROR, "Error adding listener for channel %s to app %s\n", ast_channel_name(chan), app_name);
+		return -1;
+	}
+
 	while (1) {
 		RAII_VAR(struct ast_frame *, f, NULL, ast_frame_dtor);
 		int r;
@@ -634,6 +787,7 @@ int stasis_app_exec(struct ast_channel *chan, const char *app_name, int argc,
 		}
 	}

+	app_remove_channel(app, chan);
 	res = send_end_msg(app, chan);
 	if (res != 0) {
 		ast_log(LOG_ERROR,
@@ -675,10 +829,16 @@ int stasis_app_register(const char *app_name, stasis_app_cb handler, void *data)

 	if (app) {
 		RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
+		RAII_VAR(struct ast_json *, blob, NULL, ast_json_unref);
 		SCOPED_LOCK(app_lock, app, ao2_lock, ao2_unlock);

-		msg = app_event_create("application-replaced", NULL, NULL);
-		app->handler(app->data, app_name, msg);
+		blob = ast_json_pack("{s: s}", "application", app_name);
+		if (blob) {
+			msg = stasis_json_event_application_replaced_create(blob);
+			if (msg) {
+				app->handler(app->data, app_name, msg);
+			}
+		}

 		app->handler = handler;
 		ao2_cleanup(app->data);
@@ -706,6 +866,82 @@ void stasis_app_unregister(const char *app_name)
 	}
 }

+static struct ast_json *handle_blob_dtmf(struct ast_channel_blob *obj)
+{
+	RAII_VAR(struct ast_json *, extra, NULL, ast_json_unref);
+	RAII_VAR(struct ast_json *, msg, NULL, ast_json_unref);
+	const char *direction;
+
+	/* To simplify events, we'll only generate on receive */
+	direction = ast_json_string_get(
+		ast_json_object_get(obj->blob, "direction"));
+
+	if (strcmp("Received", direction) != 0) {
+		return NULL;
+	}
+
+	extra = ast_json_pack(
+		"{s: o}",
+		"digit", ast_json_ref(ast_json_object_get(obj->blob, "digit")));
+	if (!extra) {
+		return NULL;
+	}
+
+	return stasis_json_event_channel_dtmf_received_create(obj->snapshot, extra);
+}
+
+/* To simplify events, we'll only generate on DTMF end (dtmf_end type) */
+static void sub_dtmf_handler(void *data,
+		struct stasis_subscription *sub,
+		struct stasis_topic *topic,
+		struct stasis_message *message)
+{
+	struct ast_channel_blob *obj = stasis_message_data(message);
+	generic_blob_handler(obj, handle_blob_dtmf);
+}
+
+static struct ast_json *handle_blob_userevent(struct ast_channel_blob *obj)
+{
+	return stasis_json_event_channel_userevent_create(obj->snapshot, obj->blob);
+}
+
+static void sub_userevent_handler(void *data,
+		struct stasis_subscription *sub,
+		struct stasis_topic *topic,
+		struct stasis_message *message)
+{
+	struct ast_channel_blob *obj = stasis_message_data(message);
+	generic_blob_handler(obj, handle_blob_userevent);
+}
+
+static struct ast_json *handle_blob_hangup_request(struct ast_channel_blob *obj)
+{
+	return stasis_json_event_channel_hangup_request_create(obj->snapshot, obj->blob);
+}
+
+static void sub_hangup_request_handler(void *data,
+		struct stasis_subscription *sub,
+		struct stasis_topic *topic,
+		struct stasis_message *message)
+{
+	struct ast_channel_blob *obj = stasis_message_data(message);
+	generic_blob_handler(obj, handle_blob_hangup_request);
+}
+
+static struct ast_json *handle_blob_varset(struct ast_channel_blob *obj)
+{
+	return stasis_json_event_channel_varset_create(obj->snapshot, obj->blob);
+}
+
+static void sub_varset_handler(void *data,
+		struct stasis_subscription *sub,
+		struct stasis_topic *topic,
+		struct stasis_message *message)
+{
+	struct ast_channel_blob *obj = stasis_message_data(message);
+	generic_blob_handler(obj, handle_blob_varset);
+}
+
 static int load_module(void)
 {
 	int r = 0;
@@ -722,13 +958,30 @@ static int load_module(void)
 		return AST_MODULE_LOAD_FAILURE;
 	}

-	return r;
+	channel_router = stasis_message_router_create(stasis_caching_get_topic(ast_channel_topic_all_cached()));
+	if (!channel_router) {
+		return AST_MODULE_LOAD_FAILURE;
+	}
+
+	r |= stasis_message_router_add(channel_router, stasis_cache_update_type(), sub_snapshot_handler, NULL);
+	r |= stasis_message_router_add(channel_router, ast_channel_user_event_type(), sub_userevent_handler, NULL);
+	r |= stasis_message_router_add(channel_router, ast_channel_varset_type(), sub_varset_handler, NULL);
+	r |= stasis_message_router_add(channel_router, ast_channel_dtmf_begin_type(), sub_dtmf_handler, NULL);
+	r |= stasis_message_router_add(channel_router, ast_channel_hangup_request_type(), sub_hangup_request_handler, NULL);
+	if (r) {
+		return AST_MODULE_LOAD_FAILURE;
+	}
+
+	return AST_MODULE_LOAD_SUCCESS;
 }

 static int unload_module(void)
 {
 	int r = 0;

+	stasis_message_router_unsubscribe(channel_router);
+	channel_router = NULL;
+
 	ao2_cleanup(__apps_registry);
 	__apps_registry = NULL;