Split caching out from the stasis_caching_topic.

In working with res_stasis, I discovered a significant limitation to
the current structure of stasis_caching_topics: you cannot subscribe
to cache updates for a single channel/bridge/endpoint/etc.

To address this, this patch splits the cache away from the
stasis_caching_topic, making it a first class object. The stasis_cache
object is shared amongst individual stasis_caching_topics that are
created per channel/endpoint/etc. These are still forwarded to global
whatever_all_cached topics, so their use from most of the code does
not change.

In making these changes, I noticed that we frequently used a similar
pattern for bridges, endpoints and channels:

     single_topic  ---------------->  all_topic
           ^
           |
     single_topic_cached  ----+---->  all_topic_cached
                              |
                              +---->  cache

This pattern was extracted as the 'Stasis Caching Pattern', defined in
stasis_caching_pattern.h. This avoids a lot of duplicate code between
the different domain objects.

Since the cache is now disassociated from its upstream caching topics,
this also necessitated a change to how the 'guaranteed' flag worked
for retrieving from a cache. The code for handling the caching
guarantee was extracted into a 'stasis_topic_wait' function, which
works for any stasis_topic.

(closes issue ASTERISK-22002)
Review: https://reviewboard.asterisk.org/r/2672/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@395954 65c4cc65-6c06-0410-ace0-fbb531ad65f3

apps/app_meetme.c

@@ -1167,7 +1167,7 @@ static int meetme_stasis_init(void)
 	STASIS_MESSAGE_TYPE_INIT(meetme_talk_request_type);
 
 	meetme_event_message_router = stasis_message_router_create(
-		stasis_caching_get_topic(ast_channel_topic_all_cached()));
+		ast_channel_cache());
 
 	if (!meetme_event_message_router) {
 		meetme_stasis_cleanup();

apps/app_voicemail.c

@@ -12640,7 +12640,7 @@ static void start_poll_thread(void)
 	mwi_sub_sub = stasis_subscribe(ast_mwi_topic_all(), mwi_event_cb, NULL);
 
 	if (mwi_sub_sub) {
-		struct ao2_container *cached = stasis_cache_dump(ast_mwi_topic_cached(), stasis_subscription_change_type());
+		struct ao2_container *cached = stasis_cache_dump(ast_mwi_state_cache(), stasis_subscription_change_type());
 		if (cached) {
 			ao2_callback(cached, OBJ_MULTIPLE | OBJ_NODATA, dump_cache, NULL);
 		}

apps/confbridge/confbridge_manager.c

@@ -344,7 +344,7 @@ int manager_confbridge_init(void)
 	STASIS_MESSAGE_TYPE_INIT(confbridge_talking_type);
 
 	bridge_state_router = stasis_message_router_create(
-		stasis_caching_get_topic(ast_bridge_topic_all_cached()));
+		ast_bridge_topic_all_cached());
 
 	if (!bridge_state_router) {
 		return -1;
@@ -415,7 +415,7 @@ int manager_confbridge_init(void)
 	}
 
 	channel_state_router = stasis_message_router_create(
-		stasis_caching_get_topic(ast_channel_topic_all_cached()));
+		ast_channel_topic_all_cached());
 
 	if (!channel_state_router) {
 		manager_confbridge_shutdown();

channels/chan_dahdi.c

@@ -4822,7 +4822,7 @@ static int has_voicemail(struct dahdi_pvt *p)
 	}
 
 	ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
-	mwi_message = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+	mwi_message = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 
 	if (mwi_message) {
 		struct ast_mwi_state *mwi_state = stasis_message_data(mwi_message);

channels/chan_iax2.c

@@ -8803,7 +8803,7 @@ static int update_registry(struct sockaddr_in *sin, int callno, char *devtype, i
 			}
 
 			ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
-			msg = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+			msg = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 
 			if (msg) {
 				struct ast_mwi_state *mwi_state = stasis_message_data(msg);

channels/chan_mgcp.c

@@ -508,7 +508,7 @@ static int has_voicemail(struct mgcp_endpoint *p)
 
 	ast_str_set(&uniqueid, 0, "%s@%s", mbox, cntx);
 
-	msg = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+	msg = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 
 	if (msg) {
 		struct ast_mwi_state *mwi_state = stasis_message_data(msg);

channels/chan_sip.c

@@ -28386,7 +28386,7 @@ static int get_cached_mwi(struct sip_peer *peer, int *new, int *old)
 		ast_str_reset(uniqueid);
 		ast_str_set(&uniqueid, 0, "%s@%s", mailbox->mailbox, S_OR(mailbox->context, "default"));
 
-		msg = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+		msg = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 		if (!msg) {
 			continue;
 		}

channels/chan_unistim.c

@@ -5502,7 +5502,7 @@ static int unistim_send_mwi_to_peer(struct unistim_line *peer, unsigned int tick
 
 	ast_str_set(&uniqueid, 0, "%s@%s", mailbox, context);
 
-	msg = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+	msg = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 
 	if (msg) {
 		struct ast_mwi_state *mwi_state = stasis_message_data(msg);

channels/sig_pri.c

@@ -8956,7 +8956,7 @@ static void sig_pri_mwi_cache_update(struct sig_pri_span *pri)
 		ast_str_reset(uniqueid);
 		ast_str_set(&uniqueid, 0, "%s@%s", pri->mbox[idx].number, pri->mbox[idx].context);
 
-		msg = stasis_cache_get(ast_mwi_topic_cached(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
+		msg = stasis_cache_get(ast_mwi_state_cache(), ast_mwi_state_type(), ast_str_buffer(uniqueid));
 		if (!msg) {
 			/* No cached event for this mailbox. */
 			continue;

include/asterisk/app.h

@@ -1251,7 +1251,13 @@ struct stasis_topic *ast_mwi_topic(const char *uniqueid);
  * \retval NULL if it has not been allocated
  * \since 12
  */
-struct stasis_caching_topic *ast_mwi_topic_cached(void);
+struct stasis_topic *ast_mwi_topic_cached(void);
+
+/*!
+ * \brief Backend cache for ast_mwi_topic_cached().
+ * \retval Cache of \ref ast_mwi_state.
+ */
+struct stasis_cache *ast_mwi_state_cache(void);
 
 /*!
  * \brief Get the \ref stasis message type for MWI messages

include/asterisk/bridge.h

@@ -277,6 +277,8 @@ struct ast_bridge {
 	struct ast_bridge_technology *technology;
 	/*! Private information unique to the bridge technology */
 	void *tech_pvt;
+	/*! Per-bridge topics */
+	struct stasis_cp_single *topics;
 	/*! Call ID associated with the bridge */
 	struct ast_callid *callid;
 	/*! Linked list of channels participating in the bridge */

include/asterisk/channel.h

@@ -4185,6 +4185,21 @@ struct varshead *ast_channel_get_vars(struct ast_channel *chan);
  */
 struct stasis_topic *ast_channel_topic(struct ast_channel *chan);
 
+/*!
+ * \since 12
+ * \brief A topic which publishes the events for a particular channel.
+ *
+ * \ref ast_channel_snapshot messages are replaced with \ref stasis_cache_update
+ *
+ * If the given \a chan is \c NULL, ast_channel_topic_all_cached() is returned.
+ *
+ * \param chan Channel, or \c NULL.
+ *
+ * \retval Topic for channel's events.
+ * \retval ast_channel_topic_all() if \a chan is \c NULL.
+ */
+struct stasis_topic *ast_channel_topic_cached(struct ast_channel *chan);
+
 /*!
  * \brief Get the bridge associated with a channel
  * \since 12.0.0

include/asterisk/channel_internal.h

@@ -23,5 +23,5 @@ struct ast_channel *__ast_channel_internal_alloc(void (*destructor)(void *obj),
 void ast_channel_internal_finalize(struct ast_channel *chan);
 int ast_channel_internal_is_finalized(struct ast_channel *chan);
 void ast_channel_internal_cleanup(struct ast_channel *chan);
-void ast_channel_internal_setup_topics(struct ast_channel *chan);
+int ast_channel_internal_setup_topics(struct ast_channel *chan);
 

include/asterisk/devicestate.h

@@ -307,7 +307,14 @@ struct stasis_topic *ast_device_state_topic(const char *device);
  * \retval NULL if it has not been allocated
  * \since 12
  */
-struct stasis_caching_topic *ast_device_state_topic_cached(void);
+struct stasis_topic *ast_device_state_topic_cached(void);
+
+/*!
+ * \brief Backend cache for ast_device_state_topic_cached()
+ * \retval Cache of \ref ast_device_state_message.
+ * \since 12
+ */
+struct stasis_cache *ast_device_state_cache(void);
 
 /*!
  * \brief Get the Stasis message type for device state messages

include/asterisk/presencestate.h

@@ -168,7 +168,14 @@ struct stasis_topic *ast_presence_state_topic_all(void);
  * \retval Caching Stasis topic for presence state messages
  * \since 12
  */
-struct stasis_caching_topic *ast_presence_state_topic_cached(void);
+struct stasis_topic *ast_presence_state_topic_cached(void);
+
+/*!
+ * \brief Backend cache for ast_presence_state_topic_cached()
+ * \retval Cache of \ref ast_presence_state_message.
+ * \since 12
+ */
+struct stasis_cache *ast_presence_state_cache(void);
 
 /*!
  * \brief Stasis message payload representing a presence state update

include/asterisk/stasis.h

@@ -94,13 +94,24 @@
  * in the system, and it's desirable to query that state from the cache without
  * locking the original object. It's also desirable for subscribers of the
  * caching topic to receive messages that have both the old cache value and the
- * new value being put into the cache. For this, we have
+ * new value being put into the cache. For this, we have stasis_cache_create()
- * stasis_caching_topic_create(), providing it with the topic which publishes
+ * and stasis_caching_topic_create(), providing them with the topic which
- * the messages that you wish to cache, and a function that can identify
+ * publishes the messages that you wish to cache, and a function that can
- * cacheable messages.
+ * identify cacheable messages.
  *
- * The returned \ref stasis_caching_topic provides a topic that forwards
+ * The \ref stasis_cache is designed so that it may be shared amongst several
- * non-cacheable messages unchanged. A cacheable message is wrapped in a \ref
+ * \ref stasis_caching_topic objects. This allows you to have individual caching
+ * topics per-object (i.e. so you can subscribe to updates for a single object),
+ * and still have a single cache to query for the state of all objects. While a
+ * cache may be shared amongst different message types, such a usage is probably
+ * not a good idea.
+ *
+ * The \ref stasis_cache can only be written to by \ref stasis_caching_topics.
+ * It's a thread safe container, so freely use the stasis_cache_get() and
+ * stasis_cache_dump() to query the cache.
+ *
+ * The \ref stasis_caching_topic provides a topic that forwards non-cacheable
+ * messages unchanged. A cacheable message is wrapped in a \ref
  * stasis_cache_update message which provides the old snapshot (or \c NULL if
  * this is a new cache entry), and the new snapshot (or \c NULL if the entry was
  * removed from the cache). A stasis_cache_clear_create() message must be sent
@@ -111,6 +122,9 @@
  * stasis_caching_topic will not be freed until after it has been unsubscribed,
  * and all other ao2_ref()'s have been cleaned up.
  *
+ * The \ref stasis_cache object is a normal AO2 managed object, which can be
+ * release with ao2_cleanup().
+ *
  * \par stasis_subscriber
  *
  * Any topic may be subscribed to by simply providing stasis_subscribe() the
@@ -345,6 +359,15 @@ void stasis_forward_message(struct stasis_topic *topic,
 			    struct stasis_topic *publisher_topic,
 			    struct stasis_message *message);
 
+/*!
+ * \brief Wait for all pending messages on a given topic to be processed.
+ * \param topic Topic to await pending messages on.
+ * \return 0 on success.
+ * \return Non-zero on error.
+ * \since 12
+ */
+int stasis_topic_wait(struct stasis_topic *topic);
+
 /*! @} */
 
 /*! @{ */
@@ -514,6 +537,8 @@ struct stasis_message_type *stasis_subscription_change_type(void);
 
 /*! @} */
 
+/*! @{ */
+
 /*!
  * \brief Pool for topic aggregation
  */
@@ -574,23 +599,18 @@ struct stasis_message_type *stasis_cache_clear_type(void);
 
 /*! @{ */
 
+/*!
+ * \brief A message cache, for use with \ref stasis_caching_topic.
+ * \since 12
+ */
+struct stasis_cache;
+
 /*!
  * \brief A topic wrapper, which caches certain messages.
  * \since 12
  */
 struct stasis_caching_topic;
 
-/*!
- * \brief A message which instructs the caching topic to remove an entry from its cache.
- *
- * \param message Message representative of the cache entry that should be cleared.
- *     This will become the data held in the stasis_cache_clear message.
- *
- * \return Message which, when sent to the \a topic, will clear the item from the cache.
- * \return \c NULL on error.
- * \since 12
- */
-struct stasis_message *stasis_cache_clear_create(struct stasis_message *message);
 
 /*!
  * \brief Callback extract a unique identity from a snapshot message.
@@ -605,6 +625,21 @@ struct stasis_message *stasis_cache_clear_create(struct stasis_message *message)
  */
 typedef const char *(*snapshot_get_id)(struct stasis_message *message);
 
+/*!
+ * \brief Create a cache.
+ *
+ * This is the backend store for a \ref stasis_caching_topic. The cache is
+ * thread safe, allowing concurrent reads and writes.
+ *
+ * The returned object is AO2 managed, so ao2_cleanup() when you're done.
+ *
+ * \param id_fn Callback to extract the id from a snapshot message.
+ * \return New cache indexed by \a id_fn.
+ * \return \c NULL on error
+ * \since 12
+ */
+struct stasis_cache *stasis_cache_create(snapshot_get_id id_fn);
+
 /*!
  * \brief Create a topic which monitors and caches messages from another topic.
  *
@@ -613,13 +648,17 @@ typedef const char *(*snapshot_get_id)(struct stasis_message *message);
  * is updated, and a stasis_cache_update() message is forwarded, which has both
  * the original snapshot message and the new message.
  *
+ * The returned object is AO2 managed, so ao2_cleanup() when done with it.
+ *
  * \param original_topic Topic publishing snapshot messages.
- * \param id_fn Callback to extract the id from a snapshot message.
+ * \param cache Backend cache in which to keep snapshots.
  * \return New topic which changes snapshot messages to stasis_cache_update()
  *         messages, and forwards all other messages from the original topic.
+ * \return \c NULL on error
  * \since 12
  */
-struct stasis_caching_topic *stasis_caching_topic_create(struct stasis_topic *original_topic, snapshot_get_id id_fn);
+struct stasis_caching_topic *stasis_caching_topic_create(
+	struct stasis_topic *original_topic, struct stasis_cache *cache);
 
 /*!
  * \brief Unsubscribes a caching topic from its upstream topic.
@@ -651,53 +690,55 @@ struct stasis_caching_topic *stasis_caching_unsubscribe_and_join(
 /*!
  * \brief Returns the topic of cached events from a caching topics.
  * \param caching_topic The caching topic.
- * \return The topic that publishes cache update events, along with passthrough events
+ * \return The topic that publishes cache update events, along with passthrough
- *         from the underlying topic.
+ *         events from the underlying topic.
  * \return \c NULL if \a caching_topic is \c NULL.
  * \since 12
  */
-struct stasis_topic *stasis_caching_get_topic(struct stasis_caching_topic *caching_topic);
+struct stasis_topic *stasis_caching_get_topic(
+	struct stasis_caching_topic *caching_topic);
+
+/*!
+ * \brief A message which instructs the caching topic to remove an entry from
+ * its cache.
+ *
+ * \param message Message representative of the cache entry that should be
+ *                cleared. This will become the data held in the
+ *                stasis_cache_clear message.
+ *
+ * \return Message which, when sent to a \ref stasis_caching_topic, will clear
+ *         the item from the cache.
+ * \return \c NULL on error.
+ * \since 12
+ */
+struct stasis_message *stasis_cache_clear_create(struct stasis_message *message);
 
 /*!
  * \brief Retrieve an item from the cache.
  *
  * The returned item is AO2 managed, so ao2_cleanup() when you're done with it.
  *
- * \param caching_topic The topic returned from stasis_caching_topic_create().
+ * \param cache The cache to query.
  * \param type Type of message to retrieve.
  * \param id Identity of the snapshot to retrieve.
  * \return Message from the cache.
  * \return \c NULL if message is not found.
  * \since 12
  */
-#define stasis_cache_get(caching_topic, type, id) stasis_cache_get_extended(caching_topic, type, id, 0)
+struct stasis_message *stasis_cache_get(
-
+	struct stasis_cache *cache, struct stasis_message_type *type,
-/*!
+	const char *id);
- * \brief Retrieve an item from the cache.
- * \param caching_topic The topic returned from stasis_caching_topic_create().
- * \param type Type of message to retrieve.
- * \param id Identity of the snapshot to retrieve.
- * \param guaranteed If set to 1 it is guaranteed that any pending messages have been processed.
- * \return Message from the cache. The cache still owns the message, so
- *         ao2_ref() if you want to keep it.
- * \return \c NULL if message is not found.
- * \since 12
- */
-struct stasis_message *stasis_cache_get_extended(struct stasis_caching_topic *caching_topic,
-					struct stasis_message_type *type,
-					const char *id,
-					unsigned int guaranteed);
 
 /*!
  * \brief Dump cached items to a subscription
- * \param caching_topic The topic returned from stasis_caching_topic_create().
+ * \param cache The cache to query.
  * \param type Type of message to dump (any type if \c NULL).
  * \return ao2_container containing all matches (must be unreffed by caller)
  * \return \c NULL on allocation error
  * \since 12
  */
-struct ao2_container *stasis_cache_dump(struct stasis_caching_topic *caching_topic,
+struct ao2_container *stasis_cache_dump(struct stasis_cache *cache,
-					struct stasis_message_type *type);
+	struct stasis_message_type *type);
 
 /*! @} */
 
@@ -831,13 +872,18 @@ int stasis_cache_init(void);
 
 /*!
  * \internal
- * \brief called by stasis_init for config initialization.
+ * \brief called by stasis_init() for config initialization.
  * \return 0 on success.
  * \return Non-zero on error.
  * \since 12
  */
 int stasis_config_init(void);
 
+/*!
+ * \internal
+ */
+int stasis_wait_init(void);
+
 struct ast_threadpool_options;
 
 /*!

include/asterisk/stasis_bridges.h

@@ -89,6 +89,22 @@ struct stasis_message_type *ast_bridge_snapshot_type(void);
  */
 struct stasis_topic *ast_bridge_topic(struct ast_bridge *bridge);
 
+/*!
+ * \since 12
+ * \brief A topic which publishes the events for a particular bridge.
+ *
+ * \ref ast_bridge_snapshot messages are replaced with stasis_cache_update
+ * messages.
+ *
+ * If the given \a bridge is \c NULL, ast_bridge_topic_all_cached() is returned.
+ *
+ * \param bridge Bridge for which to get a topic or \c NULL.
+ *
+ * \retval Topic for bridge's events.
+ * \retval ast_bridge_topic_all() if \a bridge is \c NULL.
+ */
+struct stasis_topic *ast_bridge_topic_cached(struct ast_bridge *bridge);
+
 /*!
  * \since 12
  * \brief A topic which publishes the events for all bridges.
@@ -103,7 +119,14 @@ struct stasis_topic *ast_bridge_topic_all(void);
  *
  * \retval Caching topic for all bridge events.
  */
-struct stasis_caching_topic *ast_bridge_topic_all_cached(void);
+struct stasis_topic *ast_bridge_topic_all_cached(void);
+
+/*!
+ * \since 12
+ * \brief Backend cache for ast_bridge_topic_all_cached().
+ * \retval Cache of \ref ast_bridge_snapshot.
+ */
+struct stasis_cache *ast_bridge_cache(void);
 
 /*!
  * \since 12
@@ -408,6 +431,15 @@ struct ast_bridge_snapshot *ast_bridge_snapshot_get_latest(
 	const char *bridge_id);
 
 /*!
+ * \internal
+ * \brief Initialize the topics for a single bridge.
+ * \return 0 on success.
+ * \return Non-zero on error.
+ */
+int bridge_topics_init(struct ast_bridge *bridge);
+
+/*!
+ * \internal
  * \brief Initialize the stasis bridging topic and message types
  * \retval 0 on success
  * \retval -1 on failure

include/asterisk/stasis_cache_pattern.h

@@ -0,0 +1,153 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * David M. Lee, II <dlee@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+#ifndef _ASTERISK_STASIS_CACHE_PATTERN_H
+#define _ASTERISK_STASIS_CACHE_PATTERN_H
+
+/*! \file
+ *
+ * \brief Caching pattern for \ref stasis topics.
+ *
+ * A typical pattern for Stasis objects is to have individual objects, which
+ * have their own topic and caching topic. These individual topics feed an
+ * upstream aggregate topics, and a shared cache.
+ *
+ * The \ref stasis_cp_all object contains the aggregate topics and shared cache.
+ * This is built with the base name for the topics, and the identity function to
+ * identify messages in the cache.
+ *
+ * The \ref stasis_cp_single object contains the \ref stasis_topic for a single
+ * instance, and the corresponding \ref stasis_caching_topic.
+ *
+ * Since the \ref stasis_cp_single object has subscriptions for forwarding
+ * and caching, it must be disposed of using stasis_cp_single_unsubscribe()
+ * instead of simply ao2_cleanup().
+ */
+
+#include "asterisk/stasis.h"
+
+/*!
+ * \brief The 'all' side of the cache pattern. These are typically built as
+ * global objects for specific modules.
+ */
+struct stasis_cp_all;
+
+/*!
+ * \brief Create an all instance of the cache pattern.
+ *
+ * This object is AO2 managed, so dispose of it with ao2_cleanup().
+ *
+ * \param name Base name of the topics.
+ * \param id_fn Identity function for the cache.
+ * \return All side instance.
+ * \return \c NULL on error.
+ */
+struct stasis_cp_all *stasis_cp_all_create(const char *name,
+	snapshot_get_id id_fn);
+
+/*!
+ * \brief Get the aggregate topic.
+ *
+ * This topic aggregates all messages published to corresponding
+ * stasis_cp_single_topic() topics.
+ *
+ * \param all All side caching pattern object.
+ * \return The aggregate topic.
+ * \return \c NULL if \a all is \c NULL
+ */
+struct stasis_topic *stasis_cp_all_topic(struct stasis_cp_all *all);
+
+/*!
+ * \brief Get the caching topic.
+ *
+ * This topic aggregates all messages from the corresponding
+ * stasis_cp_single_topic_cached() topics.
+ *
+ * Note that one normally only subscribes to the caching topic, since data
+ * is fed to it from its upstream topic.
+ *
+ * \param all All side caching pattern object.
+ * \return The aggregate caching topic.
+ * \return \c NULL if \a all is \c NULL
+ */
+struct stasis_topic *stasis_cp_all_topic_cached(
+	struct stasis_cp_all *all);
+
+/*!
+ * \brief Get the cache.
+ *
+ * This is the shared cache for all corresponding \ref stasis_cp_single objects.
+ *
+ * \param all All side caching pattern object.
+ * \return The cache.
+ * \return \c NULL if \a all is \c NULL
+ */
+struct stasis_cache *stasis_cp_all_cache(struct stasis_cp_all *all);
+
+/*!
+ * \brief The 'one' side of the cache pattern. These are built per-instance for
+ * some corresponding object, and must be explicitly disposed of using
+ * stasis_cp_single_unsubscribe().
+ */
+struct stasis_cp_single;
+
+/*!
+ * \brief Create the 'one' side of the cache pattern.
+ *
+ * Dispose of using stasis_cp_single_unsubscribe().
+ *
+ * \param all Corresponding all side.
+ * \param name Base name for the topics.
+ * \return One side instance
+ */
+struct stasis_cp_single *stasis_cp_single_create(struct stasis_cp_all *all,
+	const char *name);
+
+/*!
+ * \brief Stops caching and forwarding messages.
+ *
+ * \param one One side of the cache pattern.
+ */
+void stasis_cp_single_unsubscribe(struct stasis_cp_single *one);
+
+/*!
+ * \brief Get the topic for this instance.
+ *
+ * This is the topic to which one would post instance-specific messages, or
+ * subscribe for single-instance, uncached messages.
+ *
+ * \param one One side of the cache pattern.
+ * \return The main topic.
+ * \return \c NULL if \a one is \c NULL
+ */
+struct stasis_topic *stasis_cp_single_topic(struct stasis_cp_single *one);
+
+/*!
+ * \brief Get the caching topic for this instance.
+ *
+ * Note that one normally only subscribes to the caching topic, since data
+ * is fed to it from its upstream topic.
+ *
+ * \param one One side of the cache pattern.
+ * \return The caching topic.
+ * \return \c NULL if \a one is \c NULL
+ */
+struct stasis_topic *stasis_cp_single_topic_cached(
+	struct stasis_cp_single *one);
+
+#endif /* _ASTERISK_STASIS_CACHE_PATTERN_H */

include/asterisk/stasis_channels.h

@@ -106,6 +106,8 @@ struct ast_channel_blob {
  */
 struct ast_multi_channel_blob;
 
+struct stasis_cp_all *ast_channel_cache_all(void);
+
 /*!
  * \since 12
  * \brief A topic which publishes the events for all channels.
@@ -120,16 +122,23 @@ struct stasis_topic *ast_channel_topic_all(void);
  *
  * \retval Topic for all channel events.
  */
-struct stasis_caching_topic *ast_channel_topic_all_cached(void);
+struct stasis_topic *ast_channel_topic_all_cached(void);
 
 /*!
  * \since 12
- * \brief A caching topic which caches \ref ast_channel_snapshot messages from
+ * \brief Primary channel cache, indexed by Uniqueid.
- * ast_channel_events_all(void) and indexes them by name.
  *
- * \retval Topic for all channel events.
+ * \retval Cache of \ref ast_channel_snapshot.
  */
-struct stasis_caching_topic *ast_channel_topic_all_cached_by_name(void);
+struct stasis_cache *ast_channel_cache(void);
+
+/*!
+ * \since 12
+ * \brief Secondary channel cache, indexed by name.
+ *
+ * \retval Cache of \ref ast_channel_snapshot.
+ */
+struct stasis_cache *ast_channel_cache_by_name(void);
 
 /*!
  * \since 12
@@ -551,7 +560,9 @@ int ast_channel_snapshot_caller_id_equal(
 
 /*!
  * \brief Initialize the stasis channel topic and message types
+ * \return 0 on success
+ * \return Non-zero on error
  */
-void ast_stasis_channels_init(void);
+int ast_stasis_channels_init(void);
 
 #endif /* STASIS_CHANNELS_H_ */

include/asterisk/stasis_endpoints.h

@@ -30,6 +30,7 @@
 #include "asterisk/endpoints.h"
 #include "asterisk/json.h"
 #include "asterisk/stasis.h"
+#include "asterisk/stasis_cache_pattern.h"
 #include "asterisk/stringfields.h"
 
 /*! \addtogroup StasisTopicsAndMessages
@@ -143,6 +144,31 @@ struct ast_endpoint_snapshot *ast_endpoint_snapshot_create(
  */
 struct stasis_topic *ast_endpoint_topic(struct ast_endpoint *endpoint);
 
+/*!
+ * \brief Returns the topic for a specific endpoint.
+ *
+ * \ref ast_endpoint_snapshot messages are replaced with
+ * \ref stasis_cache_update
+ *
+ * \param endpoint The endpoint.
+ * \return The topic for the given endpoint.
+ * \return ast_endpoint_topic_all() if endpoint is \c NULL.
+ * \since 12
+ */
+struct stasis_topic *ast_endpoint_topic_cached(struct ast_endpoint *endpoint);
+
+/*!
+ * \internal
+ * \brief Cache and global topics for endpoints.
+ *
+ * This is public simply to be used by endpoints.c. Please use the accessor
+ * functions (ast_endpoint_topic_all(), ast_endpoint_topic_all_cached(),
+ * ast_endpoint_cache(), etc.) instead of calling this directly.
+ *
+ * \since 12
+ */
+struct stasis_cp_all *ast_endpoint_cache_all(void);
+
 /*!
  * \brief Topic for all endpoint releated messages.
  * \since 12
@@ -153,7 +179,14 @@ struct stasis_topic *ast_endpoint_topic_all(void);
  * \brief Cached topic for all endpoint related messages.
  * \since 12
  */
-struct stasis_caching_topic *ast_endpoint_topic_all_cached(void);
+struct stasis_topic *ast_endpoint_topic_all_cached(void);
+
+/*!
+ * \brief Backend cache for ast_endpoint_topic_all_cached().
+ * \return Cache of \ref ast_endpoint_snapshot.
+ * \since 12
+ */
+struct stasis_cache *ast_endpoint_cache(void);
 
 /*!
  * \brief Retrieve the most recent snapshot for the endpoint with the given

main/app.c

@@ -88,6 +88,7 @@ static AST_LIST_HEAD_STATIC(zombies, zombie);
  * @{ \brief Define \ref stasis topic objects for MWI
  */
 static struct stasis_topic *mwi_topic_all;
+static struct stasis_cache *mwi_state_cache;
 static struct stasis_caching_topic *mwi_topic_cached;
 static struct stasis_topic_pool *mwi_topic_pool;
 /* @} */
@@ -2696,9 +2697,14 @@ struct stasis_topic *ast_mwi_topic_all(void)
 	return mwi_topic_all;
 }
 
-struct stasis_caching_topic *ast_mwi_topic_cached(void)
+struct stasis_cache *ast_mwi_state_cache(void)
 {
-	return mwi_topic_cached;
+	return mwi_state_cache;
+}
+
+struct stasis_topic *ast_mwi_topic_cached(void)
+{
+	return stasis_caching_get_topic(mwi_topic_cached);
 }
 
 struct stasis_topic *ast_mwi_topic(const char *uniqueid)
@@ -2754,7 +2760,7 @@ int ast_publish_mwi_state_full(
 
 	if (!ast_strlen_zero(channel_id)) {
 		RAII_VAR(struct stasis_message *, chan_message,
-			stasis_cache_get(ast_channel_topic_all_cached(),
+			stasis_cache_get(ast_channel_cache(),
 					ast_channel_snapshot_type(),
 					channel_id),
 			ao2_cleanup);
@@ -2855,7 +2861,11 @@ int app_init(void)
 	if (!mwi_topic_all) {
 		return -1;
 	}
-	mwi_topic_cached = stasis_caching_topic_create(mwi_topic_all, mwi_state_get_id);
+	mwi_state_cache = stasis_cache_create(mwi_state_get_id);
+	if (!mwi_state_cache) {
+		return -1;
+	}
+	mwi_topic_cached = stasis_caching_topic_create(mwi_topic_all, mwi_state_cache);
 	if (!mwi_topic_cached) {
 		return -1;
 	}

main/bridge.c

@@ -46,6 +46,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/bridge_after.h"
 #include "asterisk/stasis_bridges.h"
 #include "asterisk/stasis_channels.h"
+#include "asterisk/stasis_cache_pattern.h"
 #include "asterisk/app.h"
 #include "asterisk/file.h"
 #include "asterisk/module.h"
@@ -634,6 +635,8 @@ static void destroy_bridge(void *obj)
 	}
 
 	cleanup_video_mode(bridge);
+
+	stasis_cp_single_unsubscribe(bridge->topics);
 }
 
 struct ast_bridge *bridge_register(struct ast_bridge *bridge)
@@ -685,6 +688,13 @@ struct ast_bridge *bridge_base_init(struct ast_bridge *self, uint32_t capabiliti
 	ast_set_flag(&self->feature_flags, flags);
 	self->allowed_capabilities = capabilities;
 
+	if (bridge_topics_init(self) != 0) {
+		ast_log(LOG_WARNING, "Bridge %s: Could not initialize topics\n",
+			self->uniqueid);
+		ao2_ref(self, -1);
+		return NULL;
+	}
+
 	/* Use our helper function to find the "best" bridge technology. */
 	self->technology = find_best_technology(capabilities, self);
 	if (!self->technology) {
@@ -4397,7 +4407,7 @@ static char *complete_bridge(const char *word, int state)
 	struct ao2_iterator iter;
 	struct stasis_message *msg;
 
-	if (!(cached_bridges = stasis_cache_dump(ast_bridge_topic_all_cached(), ast_bridge_snapshot_type()))) {
+	if (!(cached_bridges = stasis_cache_dump(ast_bridge_cache(), ast_bridge_snapshot_type()))) {
 		return NULL;
 	}
 
@@ -4435,7 +4445,7 @@ static char *handle_bridge_show_all(struct ast_cli_entry *e, int cmd, struct ast
 		return NULL;
 	}
 
-	if (!(cached_bridges = stasis_cache_dump(ast_bridge_topic_all_cached(), ast_bridge_snapshot_type()))) {
+	if (!(cached_bridges = stasis_cache_dump(ast_bridge_cache(), ast_bridge_snapshot_type()))) {
 		ast_cli(a->fd, "Failed to retrieve cached bridges\n");
 		return CLI_SUCCESS;
 	}
@@ -4467,7 +4477,7 @@ static int bridge_show_specific_print_channel(void *obj, void *arg, int flags)
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 	struct ast_channel_snapshot *snapshot;
 
-	if (!(msg = stasis_cache_get(ast_channel_topic_all_cached(), ast_channel_snapshot_type(), uniqueid))) {
+	if (!(msg = stasis_cache_get(ast_channel_cache(), ast_channel_snapshot_type(), uniqueid))) {
 		return 0;
 	}
 	snapshot = stasis_message_data(msg);
@@ -4500,7 +4510,7 @@ static char *handle_bridge_show_specific(struct ast_cli_entry *e, int cmd, struc
 		return CLI_SHOWUSAGE;
 	}
 
-	msg = stasis_cache_get(ast_bridge_topic_all_cached(), ast_bridge_snapshot_type(), a->argv[2]);
+	msg = stasis_cache_get(ast_bridge_cache(), ast_bridge_snapshot_type(), a->argv[2]);
 	if (!msg) {
 		ast_cli(a->fd, "Bridge '%s' not found\n", a->argv[2]);
 		return CLI_SUCCESS;

main/cdr.c

@@ -4005,11 +4005,11 @@ int ast_cdr_engine_init(void)
 		return -1;
 	}
 
-	channel_subscription = stasis_forward_all(stasis_caching_get_topic(ast_channel_topic_all_cached()), cdr_topic);
+	channel_subscription = stasis_forward_all(ast_channel_topic_all_cached(), cdr_topic);
 	if (!channel_subscription) {
 		return -1;
 	}
-	bridge_subscription = stasis_forward_all(stasis_caching_get_topic(ast_bridge_topic_all_cached()), cdr_topic);
+	bridge_subscription = stasis_forward_all(ast_bridge_topic_all_cached(), cdr_topic);
 	if (!bridge_subscription) {
 		return -1;
 	}

main/cel.c

@@ -1551,14 +1551,14 @@ int ast_cel_engine_init(void)
 	}
 
 	cel_channel_forwarder = stasis_forward_all(
-		stasis_caching_get_topic(ast_channel_topic_all_cached()),
+		ast_channel_topic_all_cached(),
 		cel_aggregation_topic);
 	if (!cel_channel_forwarder) {
 		return -1;
 	}
 
 	cel_bridge_forwarder = stasis_forward_all(
-		stasis_caching_get_topic(ast_bridge_topic_all_cached()),
+		ast_bridge_topic_all_cached(),
 		cel_aggregation_topic);
 	if (!cel_bridge_forwarder) {
 		return -1;

main/channel_internal_api.c

@@ -44,6 +44,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/data.h"
 #include "asterisk/endpoints.h"
 #include "asterisk/indications.h"
+#include "asterisk/stasis_cache_pattern.h"
 #include "asterisk/stasis_channels.h"
 #include "asterisk/stasis_endpoints.h"
 #include "asterisk/stringfields.h"
@@ -208,7 +209,7 @@ struct ast_channel {
 	char dtmf_digit_to_emulate;			/*!< Digit being emulated */
 	char sending_dtmf_digit;			/*!< Digit this channel is currently sending out. (zero if not sending) */
 	struct timeval sending_dtmf_tv;		/*!< The time this channel started sending the current digit. (Invalid if sending_dtmf_digit is zero.) */
-	struct stasis_topic *topic;			/*!< Topic for all channel's events */
+	struct stasis_cp_single *topics;		/*!< Topic for all channel's events */
 	struct stasis_subscription *forwarder;		/*!< Subscription for event forwarding to all topic */
 	struct stasis_subscription *endpoint_forward;	/*!< Subscription for event forwarding to endpoint's topic */
 };
@@ -1434,8 +1435,8 @@ void ast_channel_internal_cleanup(struct ast_channel *chan)
 	chan->forwarder = stasis_unsubscribe(chan->forwarder);
 	chan->endpoint_forward = stasis_unsubscribe(chan->endpoint_forward);
 
-	ao2_cleanup(chan->topic);
+	stasis_cp_single_unsubscribe(chan->topics);
-	chan->topic = NULL;
+	chan->topics = NULL;
 }
 
 void ast_channel_internal_finalize(struct ast_channel *chan)
@@ -1450,16 +1451,31 @@ int ast_channel_internal_is_finalized(struct ast_channel *chan)
 
 struct stasis_topic *ast_channel_topic(struct ast_channel *chan)
 {
-	return chan ? chan->topic : ast_channel_topic_all();
+	if (!chan) {
+		return ast_channel_topic_all();
+	}
+
+	return stasis_cp_single_topic(chan->topics);
 }
 
-int ast_channel_forward_endpoint(struct ast_channel *chan, struct ast_endpoint *endpoint)
+struct stasis_topic *ast_channel_topic_cached(struct ast_channel *chan)
+{
+	if (!chan) {
+		return ast_channel_topic_all_cached();
+	}
+
+	return stasis_cp_single_topic_cached(chan->topics);
+}
+
+int ast_channel_forward_endpoint(struct ast_channel *chan,
+	struct ast_endpoint *endpoint)
 {
 	ast_assert(chan != NULL);
 	ast_assert(endpoint != NULL);
 
 	chan->endpoint_forward =
-		stasis_forward_all(chan->topic, ast_endpoint_topic(endpoint));
+		stasis_forward_all(ast_channel_topic(chan),
+			ast_endpoint_topic(endpoint));
 
 	if (chan->endpoint_forward == NULL) {
 		return -1;
@@ -1468,19 +1484,21 @@ int ast_channel_forward_endpoint(struct ast_channel *chan, struct ast_endpoint *
 	return 0;
 }
 
-void ast_channel_internal_setup_topics(struct ast_channel *chan)
+int ast_channel_internal_setup_topics(struct ast_channel *chan)
 {
 	const char *topic_name = chan->uniqueid;
-	ast_assert(chan->topic == NULL);
+	ast_assert(chan->topics == NULL);
-	ast_assert(chan->forwarder == NULL);
 
 	if (ast_strlen_zero(topic_name)) {
 		topic_name = "<dummy-channel>";
 	}
 
-	chan->topic = stasis_topic_create(topic_name);
+	chan->topics = stasis_cp_single_create(
-	chan->forwarder = stasis_forward_all(chan->topic, ast_channel_topic_all());
+		ast_channel_cache_all(), topic_name);
 
-	ast_assert(chan->topic != NULL);
+	if (!chan->topics) {
-	ast_assert(chan->forwarder != NULL);
+		return -1;
+	}
+
+	return 0;
 }

main/cli.c

@@ -915,7 +915,7 @@ static char *handle_chanlist(struct ast_cli_entry *e, int cmd, struct ast_cli_ar
 		return CLI_SHOWUSAGE;
 
 
-	if (!(channels = stasis_cache_dump(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type()))) {
+	if (!(channels = stasis_cache_dump(ast_channel_cache_by_name(), ast_channel_snapshot_type()))) {
 		ast_cli(a->fd, "Failed to retrieve cached channels\n");
 		return CLI_SUCCESS;
 	}
@@ -1438,7 +1438,7 @@ static char *handle_showchan(struct ast_cli_entry *e, int cmd, struct ast_cli_ar
 
 	now = ast_tvnow();
 
-	if (!(msg = stasis_cache_get(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type(), a->argv[3]))) {
+	if (!(msg = stasis_cache_get(ast_channel_cache_by_name(), ast_channel_snapshot_type(), a->argv[3]))) {
 		ast_cli(a->fd, "%s is not a known channel\n", a->argv[3]);
 		return CLI_SUCCESS;
 	}
@@ -1571,7 +1571,7 @@ char *ast_complete_channels(const char *line, const char *word, int pos, int sta
 		return NULL;
 	}
 
-	if (!(cached_channels = stasis_cache_dump(ast_channel_topic_all_cached(), ast_channel_snapshot_type()))) {
+	if (!(cached_channels = stasis_cache_dump(ast_channel_cache(), ast_channel_snapshot_type()))) {
 		return NULL;
 	}
 

main/devicestate.c

@@ -196,6 +196,7 @@ static ast_cond_t change_pending;
 struct stasis_subscription *devstate_message_sub;
 
 static struct stasis_topic *device_state_topic_all;
+static struct stasis_cache *device_state_cache;
 static struct stasis_caching_topic *device_state_topic_cached;
 static struct stasis_topic_pool *device_state_topic_pool;
 
@@ -285,7 +286,7 @@ static enum ast_device_state devstate_cached(const char *device)
 	RAII_VAR(struct stasis_message *, cached_msg, NULL, ao2_cleanup);
 	struct ast_device_state_message *device_state;
 
-	cached_msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), device);
+	cached_msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), device);
 	if (!cached_msg) {
 		return AST_DEVICE_UNKNOWN;
 	}
@@ -586,7 +587,7 @@ static enum ast_device_state get_aggregate_state(char *device)
 
 	ast_devstate_aggregate_init(&aggregate);
 
-	cached = stasis_cache_dump(ast_device_state_topic_cached(), NULL);
+	cached = stasis_cache_dump(ast_device_state_cache(), NULL);
 
 	ao2_callback_data(cached, OBJ_NODATA, devstate_change_aggregator_cb, &aggregate, device);
 
@@ -598,7 +599,7 @@ static int aggregate_state_changed(char *device, enum ast_device_state new_aggre
 	RAII_VAR(struct stasis_message *, cached_aggregate_msg, NULL, ao2_cleanup);
 	struct ast_device_state_message *cached_aggregate_device_state;
 
-	cached_aggregate_msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), device);
+	cached_aggregate_msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), device);
 	if (!cached_aggregate_msg) {
 		return 1;
 	}
@@ -719,9 +720,14 @@ struct stasis_topic *ast_device_state_topic_all(void)
 	return device_state_topic_all;
 }
 
-struct stasis_caching_topic *ast_device_state_topic_cached(void)
+struct stasis_cache *ast_device_state_cache(void)
 {
-	return device_state_topic_cached;
+	return device_state_cache;
+}
+
+struct stasis_topic *ast_device_state_topic_cached(void)
+{
+	return stasis_caching_get_topic(device_state_topic_cached);
 }
 
 struct stasis_topic *ast_device_state_topic(const char *device)
@@ -777,6 +783,8 @@ static void devstate_cleanup(void)
 	devstate_message_sub = stasis_unsubscribe_and_join(devstate_message_sub);
 	ao2_cleanup(device_state_topic_all);
 	device_state_topic_all = NULL;
+	ao2_cleanup(device_state_cache);
+	device_state_cache = NULL;
 	device_state_topic_cached = stasis_caching_unsubscribe_and_join(device_state_topic_cached);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_device_state_message_type);
 	ao2_cleanup(device_state_topic_pool);
@@ -794,7 +802,11 @@ int devstate_init(void)
 	if (!device_state_topic_all) {
 		return -1;
 	}
-	device_state_topic_cached = stasis_caching_topic_create(device_state_topic_all, device_state_get_id);
+	device_state_cache = stasis_cache_create(device_state_get_id);
+	if (!device_state_cache) {
+		return -1;
+	}
+	device_state_topic_cached = stasis_caching_topic_create(device_state_topic_all, device_state_cache);
 	if (!device_state_topic_cached) {
 		return -1;
 	}
@@ -803,7 +815,7 @@ int devstate_init(void)
 		return -1;
 	}
 
-	devstate_message_sub = stasis_subscribe(stasis_caching_get_topic(ast_device_state_topic_cached()), devstate_change_collector_cb, NULL);
+	devstate_message_sub = stasis_subscribe(ast_device_state_topic_cached(), devstate_change_collector_cb, NULL);
 
 	if (!devstate_message_sub) {
 		ast_log(LOG_ERROR, "Failed to create subscription for the device state change collector\n");

main/endpoints.c

@@ -58,17 +58,29 @@ struct ast_endpoint {
 	 */
 	int max_channels;
 	/*! Topic for this endpoint's messages */
-	struct stasis_topic *topic;
+	struct stasis_cp_single *topics;
-	/*!
-	 * Forwarding subscription sending messages to ast_endpoint_topic_all()
-	 */
-	struct stasis_subscription *forward;
 	/*! Router for handling this endpoint's messages */
 	struct stasis_message_router *router;
 	/*! ast_str_container of channels associated with this endpoint */
 	struct ao2_container *channel_ids;
 };
 
+struct stasis_topic *ast_endpoint_topic(struct ast_endpoint *endpoint)
+{
+	if (!endpoint) {
+		return ast_endpoint_topic_all();
+	}
+	return stasis_cp_single_topic(endpoint->topics);
+}
+
+struct stasis_topic *ast_endpoint_topic_cached(struct ast_endpoint *endpoint)
+{
+	if (!endpoint) {
+		return ast_endpoint_topic_all_cached();
+	}
+	return stasis_cp_single_topic_cached(endpoint->topics);
+}
+
 const char *ast_endpoint_state_to_string(enum ast_endpoint_state state)
 {
 	switch (state) {
@@ -88,7 +100,7 @@ static void endpoint_publish_snapshot(struct ast_endpoint *endpoint)
 	RAII_VAR(struct stasis_message *, message, NULL, ao2_cleanup);
 
 	ast_assert(endpoint != NULL);
-	ast_assert(endpoint->topic != NULL);
+	ast_assert(endpoint->topics != NULL);
 
 	snapshot = ast_endpoint_snapshot_create(endpoint);
 	if (!snapshot) {
@@ -98,7 +110,7 @@ static void endpoint_publish_snapshot(struct ast_endpoint *endpoint)
 	if (!message) {
 		return;
 	}
-	stasis_publish(endpoint->topic, message);
+	stasis_publish(ast_endpoint_topic(endpoint), message);
 }
 
 static void endpoint_dtor(void *obj)
@@ -110,11 +122,8 @@ static void endpoint_dtor(void *obj)
 	ao2_cleanup(endpoint->router);
 	endpoint->router = NULL;
 
-	stasis_unsubscribe(endpoint->forward);
+	stasis_cp_single_unsubscribe(endpoint->topics);
-	endpoint->forward = NULL;
+	endpoint->topics = NULL;
-
-	ao2_cleanup(endpoint->topic);
-	endpoint->topic = NULL;
 
 	ao2_cleanup(endpoint->channel_ids);
 	endpoint->channel_ids = NULL;
@@ -214,18 +223,13 @@ struct ast_endpoint *ast_endpoint_create(const char *tech, const char *resource)
 		return NULL;
 	}
 
-	endpoint->topic = stasis_topic_create(endpoint->id);
+	endpoint->topics = stasis_cp_single_create(ast_endpoint_cache_all(),
-	if (!endpoint->topic) {
+		endpoint->id);
+	if (!endpoint->topics) {
 		return NULL;
 	}
 
-	endpoint->forward =
+	endpoint->router = stasis_message_router_create(ast_endpoint_topic(endpoint));
-		stasis_forward_all(endpoint->topic, ast_endpoint_topic_all());
-	if (!endpoint->forward) {
-		return NULL;
-	}
-
-	endpoint->router = stasis_message_router_create(endpoint->topic);
 	if (!endpoint->router) {
 		return NULL;
 	}
@@ -271,7 +275,7 @@ void ast_endpoint_shutdown(struct ast_endpoint *endpoint)
 		RAII_VAR(struct stasis_message *, message, NULL, ao2_cleanup);
 		message = stasis_cache_clear_create(clear_msg);
 		if (message) {
-			stasis_publish(endpoint->topic, message);
+			stasis_publish(ast_endpoint_topic(endpoint), message);
 		}
 	}
 
@@ -285,11 +289,6 @@ const char *ast_endpoint_get_resource(const struct ast_endpoint *endpoint)
 	return endpoint->resource;
 }
 
-struct stasis_topic *ast_endpoint_topic(struct ast_endpoint *endpoint)
-{
-	return endpoint ? endpoint->topic : ast_endpoint_topic_all();
-}
-
 void ast_endpoint_set_state(struct ast_endpoint *endpoint,
 	enum ast_endpoint_state state)
 {

main/manager.c

@@ -3874,7 +3874,7 @@ static int action_status(struct mansession *s, const struct message *m)
 	}
 
 	if (all) {
-		if (!(cached_channels = stasis_cache_dump(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type()))) {
+		if (!(cached_channels = stasis_cache_dump(ast_channel_cache_by_name(), ast_channel_snapshot_type()))) {
 			ast_free(str);
 			astman_send_error(s, m, "Memory Allocation Failure");
 			return 1;
@@ -3882,7 +3882,7 @@ static int action_status(struct mansession *s, const struct message *m)
 		it_chans = ao2_iterator_init(cached_channels, 0);
 		msg = ao2_iterator_next(&it_chans);
 	} else {
-		if (!(msg = stasis_cache_get(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type(), name))) {
+		if (!(msg = stasis_cache_get(ast_channel_cache_by_name(), ast_channel_snapshot_type(), name))) {
 			astman_send_error(s, m, "No such channel");
 			ast_free(str);
 			return 0;
@@ -5356,7 +5356,7 @@ static int action_coreshowchannels(struct mansession *s, const struct message *m
 		idText[0] = '\0';
 	}
 
-	if (!(channels = stasis_cache_dump(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type()))) {
+	if (!(channels = stasis_cache_dump(ast_channel_cache_by_name(), ast_channel_snapshot_type()))) {
 		astman_send_error(s, m, "Could not get cached channels");
 		return 0;
 	}

main/manager_bridges.c

@@ -350,7 +350,7 @@ static int manager_bridges_list(struct mansession *s, const struct message *m)
 		ast_str_set(&id_text, 0, "ActionID: %s\r\n", id);
 	}
 
-	bridges = stasis_cache_dump(ast_bridge_topic_all_cached(), ast_bridge_snapshot_type());
+	bridges = stasis_cache_dump(ast_bridge_cache(), ast_bridge_snapshot_type());
 	if (!bridges) {
 		astman_send_error(s, m, "Internal error");
 		return -1;
@@ -382,7 +382,7 @@ static int send_bridge_info_item_cb(void *obj, void *arg, void *data, int flags)
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 	struct ast_channel_snapshot *snapshot;
 	RAII_VAR(struct ast_str *, channel_text, NULL, ast_free);
-	msg = stasis_cache_get(ast_channel_topic_all_cached(),
+	msg = stasis_cache_get(ast_channel_cache(),
 		ast_channel_snapshot_type(), uniqueid);
 
 	if (!msg) {
@@ -432,7 +432,7 @@ static int manager_bridge_info(struct mansession *s, const struct message *m)
 		ast_str_set(&id_text, 0, "ActionID: %s\r\n", id);
 	}
 
-	msg = stasis_cache_get(ast_bridge_topic_all_cached(), ast_bridge_snapshot_type(), bridge_uniqueid);
+	msg = stasis_cache_get(ast_bridge_cache(), ast_bridge_snapshot_type(), bridge_uniqueid);
 	if (!msg) {
 		astman_send_error(s, m, "Specified BridgeUniqueid not found");
 		return -1;
@@ -489,7 +489,7 @@ int manager_bridging_init(void)
 		return -1;
 	}
 
-	bridge_topic = stasis_caching_get_topic(ast_bridge_topic_all_cached());
+	bridge_topic = ast_bridge_topic_all_cached();
 	if (!bridge_topic) {
 		return -1;
 	}

main/manager_channels.c

@@ -1269,7 +1269,7 @@ int manager_channels_init(void)
 	if (!message_router) {
 		return -1;
 	}
-	channel_topic = stasis_caching_get_topic(ast_channel_topic_all_cached());
+	channel_topic = ast_channel_topic_all_cached();
 	if (!channel_topic) {
 		return -1;
 	}

main/manager_endpoints.c

@@ -49,7 +49,11 @@ static void endpoint_state_cb(void *data, struct stasis_subscription *sub,
 	struct stasis_topic *topic,
 	struct stasis_message *message)
 {
-	stasis_forward_message(ast_manager_get_topic(), stasis_caching_get_topic(ast_endpoint_topic_all_cached()), message);
+	/* XXX This looks wrong. Nothing should post or forward to a caching
+	 * topic directly. Maybe ast_endpoint_topic() would be correct? I'd have
+	 * to dig to make sure I don't break anything, though.
+	 */
+	stasis_forward_message(ast_manager_get_topic(), ast_endpoint_topic_all_cached(), message);
 }
 
 int manager_endpoints_init(void)
@@ -64,7 +68,7 @@ int manager_endpoints_init(void)
 
 	ast_register_atexit(manager_endpoints_shutdown);
 
-	endpoint_topic = stasis_caching_get_topic(ast_endpoint_topic_all_cached());
+	endpoint_topic = ast_endpoint_topic_all_cached();
 	if (!endpoint_topic) {
 		return -1;
 	}

main/pbx.c

@@ -8042,7 +8042,7 @@ static char *handle_show_chanvar(struct ast_cli_entry *e, int cmd, struct ast_cl
 	if (a->argc != e->args + 1)
 		return CLI_SHOWUSAGE;
 
-	if (!(msg = stasis_cache_get(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type(), a->argv[3]))) {
+	if (!(msg = stasis_cache_get(ast_channel_cache_by_name(), ast_channel_snapshot_type(), a->argv[3]))) {
 		ast_cli(a->fd, "Channel '%s' not found\n", a->argv[e->args]);
 		return CLI_FAILURE;
 	}

main/presencestate.c

@@ -55,6 +55,7 @@ static const struct {
 
 STASIS_MESSAGE_TYPE_DEFN(ast_presence_state_message_type);
 struct stasis_topic *presence_state_topic_all;
+struct stasis_cache *presence_state_cache;
 struct stasis_caching_topic *presence_state_topic_cached;
 
 /*! \brief  A presence state provider */
@@ -95,7 +96,7 @@ static enum ast_presence_state presence_state_cached(const char *presence_provid
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 	struct ast_presence_state_message *presence_state;
 
-	msg = stasis_cache_get(ast_presence_state_topic_cached(), ast_presence_state_message_type(), presence_provider);
+	msg = stasis_cache_get(ast_presence_state_cache(), ast_presence_state_message_type(), presence_provider);
 
 	if (!msg) {
 		return res;
@@ -294,9 +295,14 @@ struct stasis_topic *ast_presence_state_topic_all(void)
 	return presence_state_topic_all;
 }
 
-struct stasis_caching_topic *ast_presence_state_topic_cached(void)
+struct stasis_cache *ast_presence_state_cache(void)
 {
-	return presence_state_topic_cached;
+	return presence_state_cache;
+}
+
+struct stasis_topic *ast_presence_state_topic_cached(void)
+{
+	return stasis_caching_get_topic(presence_state_topic_cached);
 }
 
 static const char *presence_state_get_id(struct stasis_message *msg)
@@ -314,6 +320,8 @@ static void presence_state_engine_cleanup(void)
 {
 	ao2_cleanup(presence_state_topic_all);
 	presence_state_topic_all = NULL;
+	ao2_cleanup(presence_state_cache);
+	presence_state_cache = NULL;
 	presence_state_topic_cached = stasis_caching_unsubscribe_and_join(presence_state_topic_cached);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_presence_state_message_type);
 }
@@ -331,7 +339,12 @@ int ast_presence_state_engine_init(void)
 		return -1;
 	}
 
-	presence_state_topic_cached = stasis_caching_topic_create(presence_state_topic_all, presence_state_get_id);
+	presence_state_cache = stasis_cache_create(presence_state_get_id);
+	if (!presence_state_cache) {
+		return -1;
+	}
+
+	presence_state_topic_cached = stasis_caching_topic_create(presence_state_topic_all, presence_state_cache);
 	if (!presence_state_topic_cached) {
 		return -1;
 	}

main/stasis.c

@@ -653,6 +653,11 @@ int stasis_init(void)
 		return -1;
 	}
 
+	if (stasis_wait_init() != 0) {
+		ast_log(LOG_ERROR, "Stasis initialization failed\n");
+		return -1;
+	}
+
 	if (pool) {
 		ast_log(LOG_ERROR, "Stasis double-initialized\n");
 		return -1;

main/stasis_bridges.c

@@ -33,6 +33,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 
 #include "asterisk/astobj2.h"
 #include "asterisk/stasis.h"
+#include "asterisk/stasis_cache_pattern.h"
 #include "asterisk/channel.h"
 #include "asterisk/stasis_bridges.h"
 #include "asterisk/stasis_channels.h"
@@ -361,6 +362,8 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 static struct ast_manager_event_blob *attended_transfer_to_ami(struct stasis_message *message);
 static struct ast_manager_event_blob *blind_transfer_to_ami(struct stasis_message *message);
 
+static struct stasis_cp_all *bridge_cache_all;
+
 /*!
  * @{ \brief Define bridge message types.
  */
@@ -372,14 +375,52 @@ STASIS_MESSAGE_TYPE_DEFN(ast_blind_transfer_type, .to_ami = blind_transfer_to_am
 STASIS_MESSAGE_TYPE_DEFN(ast_attended_transfer_type, .to_ami = attended_transfer_to_ami);
 /*! @} */
 
-/*! \brief Aggregate topic for bridge messages */
+struct stasis_cache *ast_bridge_cache(void)
-static struct stasis_topic *bridge_topic_all;
+{
+	return stasis_cp_all_cache(bridge_cache_all);
+}
 
-/*! \brief Caching aggregate topic for bridge snapshots */
+struct stasis_topic *ast_bridge_topic_all(void)
-static struct stasis_caching_topic *bridge_topic_all_cached;
+{
+	return stasis_cp_all_topic(bridge_cache_all);
+}
 
-/*! \brief Topic pool for individual bridge topics */
+struct stasis_topic *ast_bridge_topic_all_cached(void)
-static struct stasis_topic_pool *bridge_topic_pool;
+{
+	return stasis_cp_all_topic_cached(bridge_cache_all);
+}
+
+int bridge_topics_init(struct ast_bridge *bridge)
+{
+	if (ast_strlen_zero(bridge->uniqueid)) {
+		ast_log(LOG_ERROR, "Bridge id initialization required\n");
+		return -1;
+	}
+	bridge->topics = stasis_cp_single_create(bridge_cache_all,
+		bridge->uniqueid);
+	if (!bridge->topics) {
+		return -1;
+	}
+	return 0;
+}
+
+struct stasis_topic *ast_bridge_topic(struct ast_bridge *bridge)
+{
+	if (!bridge) {
+		return ast_bridge_topic_all();
+	}
+
+	return stasis_cp_single_topic(bridge->topics);
+}
+
+struct stasis_topic *ast_bridge_topic_cached(struct ast_bridge *bridge)
+{
+	if (!bridge) {
+		return ast_bridge_topic_all_cached();
+	}
+
+	return stasis_cp_single_topic_cached(bridge->topics);
+}
 
 /*! \brief Destructor for bridge snapshots */
 static void bridge_snapshot_dtor(void *obj)
@@ -425,25 +466,6 @@ struct ast_bridge_snapshot *ast_bridge_snapshot_create(struct ast_bridge *bridge
 	return snapshot;
 }
 
-struct stasis_topic *ast_bridge_topic(struct ast_bridge *bridge)
-{
-	struct stasis_topic *bridge_topic = stasis_topic_pool_get_topic(bridge_topic_pool, bridge->uniqueid);
-	if (!bridge_topic) {
-		return ast_bridge_topic_all();
-	}
-	return bridge_topic;
-}
-
-struct stasis_topic *ast_bridge_topic_all(void)
-{
-	return bridge_topic_all;
-}
-
-struct stasis_caching_topic *ast_bridge_topic_all_cached(void)
-{
-	return bridge_topic_all_cached;
-}
-
 void ast_bridge_publish_state(struct ast_bridge *bridge)
 {
 	RAII_VAR(struct ast_bridge_snapshot *, snapshot, NULL, ao2_cleanup);
@@ -464,7 +486,8 @@ void ast_bridge_publish_state(struct ast_bridge *bridge)
 	stasis_publish(ast_bridge_topic(bridge), msg);
 }
 
-static void bridge_publish_state_from_blob(struct ast_bridge_blob *obj)
+static void bridge_publish_state_from_blob(struct ast_bridge *bridge,
+	struct ast_bridge_blob *obj)
 {
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 
@@ -475,7 +498,7 @@ static void bridge_publish_state_from_blob(struct ast_bridge_blob *obj)
 		return;
 	}
 
-	stasis_publish(stasis_topic_pool_get_topic(bridge_topic_pool, obj->bridge->uniqueid), msg);
+	stasis_publish(ast_bridge_topic(bridge), msg);
 }
 
 /*! \brief Destructor for bridge merge messages */
@@ -597,7 +620,7 @@ void ast_bridge_publish_enter(struct ast_bridge *bridge, struct ast_channel *cha
 
 	/* enter blob first, then state */
 	stasis_publish(ast_bridge_topic(bridge), msg);
-	bridge_publish_state_from_blob(stasis_message_data(msg));
+	bridge_publish_state_from_blob(bridge, stasis_message_data(msg));
 }
 
 void ast_bridge_publish_leave(struct ast_bridge *bridge, struct ast_channel *chan)
@@ -610,7 +633,7 @@ void ast_bridge_publish_leave(struct ast_bridge *bridge, struct ast_channel *cha
 	}
 
 	/* state first, then leave blob (opposite of enter, preserves nesting of events) */
-	bridge_publish_state_from_blob(stasis_message_data(msg));
+	bridge_publish_state_from_blob(bridge, stasis_message_data(msg));
 	stasis_publish(ast_bridge_topic(bridge), msg);
 }
 
@@ -1043,7 +1066,7 @@ struct ast_bridge_snapshot *ast_bridge_snapshot_get_latest(const char *uniqueid)
 
 	ast_assert(!ast_strlen_zero(uniqueid));
 
-	message = stasis_cache_get(ast_bridge_topic_all_cached(),
+	message = stasis_cache_get(ast_bridge_cache(),
 			ast_bridge_snapshot_type(),
 			uniqueid);
 	if (!message) {
@@ -1058,23 +1081,6 @@ struct ast_bridge_snapshot *ast_bridge_snapshot_get_latest(const char *uniqueid)
 	return snapshot;
 }
 
-static void stasis_bridging_cleanup(void)
-{
-	ao2_cleanup(bridge_topic_all);
-	bridge_topic_all = NULL;
-	bridge_topic_all_cached = stasis_caching_unsubscribe_and_join(
-		bridge_topic_all_cached);
-	ao2_cleanup(bridge_topic_pool);
-	bridge_topic_pool = NULL;
-
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_bridge_snapshot_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_bridge_merge_message_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_entered_bridge_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_left_bridge_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_blind_transfer_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(ast_attended_transfer_type);
-}
-
 /*! \brief snapshot ID getter for caching topic */
 static const char *bridge_snapshot_get_id(struct stasis_message *msg)
 {
@@ -1086,21 +1092,38 @@ static const char *bridge_snapshot_get_id(struct stasis_message *msg)
 	return snapshot->uniqueid;
 }
 
+static void stasis_bridging_cleanup(void)
+{
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_bridge_snapshot_type);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_bridge_merge_message_type);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_entered_bridge_type);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_left_bridge_type);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_blind_transfer_type);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_attended_transfer_type);
+
+	ao2_cleanup(bridge_cache_all);
+	bridge_cache_all = NULL;
+}
+
 int ast_stasis_bridging_init(void)
 {
+	int res = 0;
+
 	ast_register_cleanup(stasis_bridging_cleanup);
 
-	STASIS_MESSAGE_TYPE_INIT(ast_bridge_snapshot_type);
+	bridge_cache_all = stasis_cp_all_create("ast_bridge_topic_all",
-	STASIS_MESSAGE_TYPE_INIT(ast_bridge_merge_message_type);
+		bridge_snapshot_get_id);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_entered_bridge_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_left_bridge_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_blind_transfer_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_attended_transfer_type);
-	bridge_topic_all = stasis_topic_create("ast_bridge_topic_all");
-	bridge_topic_all_cached = stasis_caching_topic_create(bridge_topic_all, bridge_snapshot_get_id);
-	bridge_topic_pool = stasis_topic_pool_create(bridge_topic_all);
 
-	return !bridge_topic_all
+	if (!bridge_cache_all) {
-		|| !bridge_topic_all_cached
+		return -1;
-		|| !bridge_topic_pool ? -1 : 0;
+	}
+
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_bridge_snapshot_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_bridge_merge_message_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_entered_bridge_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_left_bridge_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_blind_transfer_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_attended_transfer_type);
+
+	return res;
 }

main/stasis_cache.c

@@ -44,15 +44,18 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #endif
 
 /*! \internal */
-struct stasis_caching_topic {
+struct stasis_cache {
-	struct ao2_container *cache;
+	struct ao2_container *entries;
-	struct stasis_topic *topic;
-	struct stasis_topic *original_topic;
-	struct stasis_subscription *sub;
 	snapshot_get_id id_fn;
 };
 
-static struct stasis_message_type *cache_guarantee_type(void);
+/*! \internal */
+struct stasis_caching_topic {
+	struct stasis_cache *cache;
+	struct stasis_topic *topic;
+	struct stasis_topic *original_topic;
+	struct stasis_subscription *sub;
+};
 
 static void stasis_caching_topic_dtor(void *obj) {
 	struct stasis_caching_topic *caching_topic = obj;
@@ -136,7 +139,8 @@ static struct cache_entry *cache_entry_create(struct stasis_message_type *type,
 	ast_assert(type != NULL);
 	ast_assert(id != NULL);
 
-	entry = ao2_alloc(sizeof(*entry), cache_entry_dtor);
+	entry = ao2_alloc_options(sizeof(*entry), cache_entry_dtor,
+		AO2_ALLOC_OPT_LOCK_NOLOCK);
 	if (!entry) {
 		return NULL;
 	}
@@ -183,28 +187,62 @@ static int cache_entry_cmp(void *obj, void *arg, int flags)
 	return 0;
 }
 
-static struct stasis_message *cache_put(struct stasis_caching_topic *caching_topic, struct stasis_message_type *type, const char *id, struct stasis_message *new_snapshot)
+static void cache_dtor(void *obj)
+{
+        struct stasis_cache *cache = obj;
+
+        ao2_cleanup(cache->entries);
+        cache->entries = NULL;
+}
+
+struct stasis_cache *stasis_cache_create(snapshot_get_id id_fn)
+{
+        RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
+
+        cache = ao2_alloc_options(sizeof(*cache), cache_dtor,
+		AO2_ALLOC_OPT_LOCK_NOLOCK);
+        if (!cache) {
+                return NULL;
+        }
+
+        cache->entries = ao2_container_alloc(NUM_CACHE_BUCKETS, cache_entry_hash,
+                cache_entry_cmp);
+        if (!cache->entries) {
+                return NULL;
+        }
+
+        cache->id_fn = id_fn;
+
+        ao2_ref(cache, +1);
+        return cache;
+}
+
+static struct stasis_message *cache_put(struct stasis_cache *cache,
+	struct stasis_message_type *type, const char *id,
+	struct stasis_message *new_snapshot)
 {
 	RAII_VAR(struct cache_entry *, new_entry, NULL, ao2_cleanup);
 	RAII_VAR(struct cache_entry *, cached_entry, NULL, ao2_cleanup);
 	struct stasis_message *old_snapshot = NULL;
 
-	ast_assert(caching_topic->cache != NULL);
+	ast_assert(cache->entries != NULL);
+	ast_assert(new_snapshot == NULL ||
+		type == stasis_message_type(new_snapshot));
 
 	new_entry = cache_entry_create(type, id, new_snapshot);
 
 	if (new_snapshot == NULL) {
 		/* Remove entry from cache */
-		cached_entry = ao2_find(caching_topic->cache, new_entry, OBJ_POINTER | OBJ_UNLINK);
+		cached_entry = ao2_find(cache->entries, new_entry, OBJ_POINTER | OBJ_UNLINK);
 		if (cached_entry) {
 			old_snapshot = cached_entry->snapshot;
 			cached_entry->snapshot = NULL;
 		}
 	} else {
 		/* Insert/update cache */
-		SCOPED_AO2LOCK(lock, caching_topic->cache);
+		SCOPED_AO2LOCK(lock, cache->entries);
 
-		cached_entry = ao2_find(caching_topic->cache, new_entry, OBJ_POINTER | OBJ_NOLOCK);
+		cached_entry = ao2_find(cache->entries, new_entry, OBJ_POINTER | OBJ_NOLOCK);
 		if (cached_entry) {
 			/* Update cache. Because objects are moving, no need to update refcounts. */
 			old_snapshot = cached_entry->snapshot;
@@ -212,7 +250,7 @@ static struct stasis_message *cache_put(struct stasis_caching_topic *caching_top
 			new_entry->snapshot = NULL;
 		} else {
 			/* Insert into the cache */
-			ao2_link_flags(caching_topic->cache, new_entry, OBJ_NOLOCK);
+			ao2_link_flags(cache->entries, new_entry, OBJ_NOLOCK);
 		}
 
 	}
@@ -220,68 +258,19 @@ static struct stasis_message *cache_put(struct stasis_caching_topic *caching_top
 	return old_snapshot;
 }
 
-/*! \internal */
+struct stasis_message *stasis_cache_get(struct stasis_cache *cache, struct stasis_message_type *type, const char *id)
-struct caching_guarantee {
-	ast_mutex_t lock;
-	ast_cond_t cond;
-	unsigned int done:1;
-};
-
-static void caching_guarantee_dtor(void *obj)
-{
-	struct caching_guarantee *guarantee = obj;
-
-	ast_assert(guarantee->done == 1);
-
-	ast_mutex_destroy(&guarantee->lock);
-	ast_cond_destroy(&guarantee->cond);
-}
-
-static struct stasis_message *caching_guarantee_create(void)
-{
-	RAII_VAR(struct caching_guarantee *, guarantee, NULL, ao2_cleanup);
-	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
-
-	if (!(guarantee = ao2_alloc(sizeof(*guarantee), caching_guarantee_dtor))) {
-		return NULL;
-	}
-
-	ast_mutex_init(&guarantee->lock);
-	ast_cond_init(&guarantee->cond, NULL);
-
-	if (!(msg = stasis_message_create(cache_guarantee_type(), guarantee))) {
-		return NULL;
-	}
-
-	ao2_ref(msg, +1);
-	return msg;
-}
-
-struct stasis_message *stasis_cache_get_extended(struct stasis_caching_topic *caching_topic, struct stasis_message_type *type, const char *id, unsigned int guaranteed)
 {
 	RAII_VAR(struct cache_entry *, search_entry, NULL, ao2_cleanup);
 	RAII_VAR(struct cache_entry *, cached_entry, NULL, ao2_cleanup);
 
-	ast_assert(caching_topic->cache != NULL);
+	ast_assert(cache->entries != NULL);
-
-	if (guaranteed) {
-		RAII_VAR(struct stasis_message *, msg, caching_guarantee_create(), ao2_cleanup);
-		struct caching_guarantee *guarantee = stasis_message_data(msg);
-
-		ast_mutex_lock(&guarantee->lock);
-		stasis_publish(caching_topic->original_topic, msg);
-		while (!guarantee->done) {
-			ast_cond_wait(&guarantee->cond, &guarantee->lock);
-		}
-		ast_mutex_unlock(&guarantee->lock);
-	}
 
 	search_entry = cache_entry_create(type, id, NULL);
 	if (search_entry == NULL) {
 		return NULL;
 	}
 
-	cached_entry = ao2_find(caching_topic->cache, search_entry, OBJ_POINTER);
+	cached_entry = ao2_find(cache->entries, search_entry, OBJ_POINTER);
 	if (cached_entry == NULL) {
 		return NULL;
 	}
@@ -308,25 +297,25 @@ static int cache_dump_cb(void *obj, void *arg, int flags)
 	return 0;
 }
 
-struct ao2_container *stasis_cache_dump(struct stasis_caching_topic *caching_topic, struct stasis_message_type *type)
+struct ao2_container *stasis_cache_dump(struct stasis_cache *cache, struct stasis_message_type *type)
 {
 	struct cache_dump_data cache_dump;
 
-	ast_assert(caching_topic->cache != NULL);
+	ast_assert(cache->entries != NULL);
 
 	cache_dump.type = type;
-	cache_dump.cached = ao2_container_alloc(1, NULL, NULL);
+	cache_dump.cached = ao2_container_alloc_options(
+		AO2_ALLOC_OPT_LOCK_NOLOCK, 1, NULL, NULL);
 	if (!cache_dump.cached) {
 		return NULL;
 	}
 
-	ao2_callback(caching_topic->cache, OBJ_MULTIPLE | OBJ_NODATA, cache_dump_cb, &cache_dump);
+	ao2_callback(cache->entries, OBJ_MULTIPLE | OBJ_NODATA, cache_dump_cb, &cache_dump);
 	return cache_dump.cached;
 }
 
 STASIS_MESSAGE_TYPE_DEFN(stasis_cache_clear_type);
 STASIS_MESSAGE_TYPE_DEFN(stasis_cache_update_type);
-STASIS_MESSAGE_TYPE_DEFN(cache_guarantee_type);
 
 struct stasis_message *stasis_cache_clear_create(struct stasis_message *id_message)
 {
@@ -362,7 +351,8 @@ static struct stasis_message *update_create(struct stasis_topic *topic, struct s
 	ast_assert(topic != NULL);
 	ast_assert(old_snapshot != NULL || new_snapshot != NULL);
 
-	update = ao2_alloc(sizeof(*update), stasis_cache_update_dtor);
+	update = ao2_alloc_options(sizeof(*update), stasis_cache_update_dtor,
+		AO2_ALLOC_OPT_LOCK_NOLOCK);
 	if (!update) {
 		return NULL;
 	}
@@ -393,7 +383,8 @@ static struct stasis_message *update_create(struct stasis_topic *topic, struct s
 	return msg;
 }
 
-static void caching_topic_exec(void *data, struct stasis_subscription *sub, struct stasis_topic *topic, struct stasis_message *message)
+static void caching_topic_exec(void *data, struct stasis_subscription *sub,
+	struct stasis_topic *topic, struct stasis_message *message)
 {
 	RAII_VAR(struct stasis_caching_topic *, caching_topic_needs_unref, NULL, ao2_cleanup);
 	struct stasis_caching_topic *caching_topic = data;
@@ -401,36 +392,25 @@ static void caching_topic_exec(void *data, struct stasis_subscription *sub, stru
 
 	ast_assert(caching_topic != NULL);
 	ast_assert(caching_topic->topic != NULL);
-	ast_assert(caching_topic->id_fn != NULL);
+	ast_assert(caching_topic->cache != NULL);
+	ast_assert(caching_topic->cache->id_fn != NULL);
 
 	if (stasis_subscription_final_message(sub, message)) {
 		caching_topic_needs_unref = caching_topic;
 	}
 
-	/* Handle cache guarantee event */
-	if (cache_guarantee_type() == stasis_message_type(message)) {
-		struct caching_guarantee *guarantee = stasis_message_data(message);
-
-		ast_mutex_lock(&guarantee->lock);
-		guarantee->done = 1;
-		ast_cond_signal(&guarantee->cond);
-		ast_mutex_unlock(&guarantee->lock);
-
-		return;
-	}
-
 	/* Handle cache clear event */
 	if (stasis_cache_clear_type() == stasis_message_type(message)) {
 		RAII_VAR(struct stasis_message *, old_snapshot, NULL, ao2_cleanup);
 		RAII_VAR(struct stasis_message *, update, NULL, ao2_cleanup);
 		struct stasis_message *clear_msg = stasis_message_data(message);
-		const char *clear_id = caching_topic->id_fn(clear_msg);
+		const char *clear_id = caching_topic->cache->id_fn(clear_msg);
 		struct stasis_message_type *clear_type = stasis_message_type(clear_msg);
 
 		ast_assert(clear_type != NULL);
 
 		if (clear_id) {
-			old_snapshot = cache_put(caching_topic, clear_type, clear_id, NULL);
+			old_snapshot = cache_put(caching_topic->cache, clear_type, clear_id, NULL);
 			if (old_snapshot) {
 				update = update_create(topic, old_snapshot, NULL);
 				stasis_publish(caching_topic->topic, update);
@@ -444,7 +424,7 @@ static void caching_topic_exec(void *data, struct stasis_subscription *sub, stru
 		}
 	}
 
-	id = caching_topic->id_fn(message);
+	id = caching_topic->cache->id_fn(message);
 	if (id == NULL) {
 		/* Object isn't cached; forward */
 		stasis_forward_message(caching_topic->topic, topic, message);
@@ -453,7 +433,7 @@ static void caching_topic_exec(void *data, struct stasis_subscription *sub, stru
 		RAII_VAR(struct stasis_message *, old_snapshot, NULL, ao2_cleanup);
 		RAII_VAR(struct stasis_message *, update, NULL, ao2_cleanup);
 
-		old_snapshot = cache_put(caching_topic, stasis_message_type(message), id, message);
+		old_snapshot = cache_put(caching_topic->cache, stasis_message_type(message), id, message);
 
 		update = update_create(topic, old_snapshot, message);
 		if (update == NULL) {
@@ -464,7 +444,7 @@ static void caching_topic_exec(void *data, struct stasis_subscription *sub, stru
 	}
 }
 
-struct stasis_caching_topic *stasis_caching_topic_create(struct stasis_topic *original_topic, snapshot_get_id id_fn)
+struct stasis_caching_topic *stasis_caching_topic_create(struct stasis_topic *original_topic, struct stasis_cache *cache)
 {
 	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
 	struct stasis_subscription *sub;
@@ -476,23 +456,19 @@ struct stasis_caching_topic *stasis_caching_topic_create(struct stasis_topic *or
 		return NULL;
 	}
 
-	caching_topic = ao2_alloc(sizeof(*caching_topic), stasis_caching_topic_dtor);
+	caching_topic = ao2_alloc_options(sizeof(*caching_topic),
+		stasis_caching_topic_dtor, AO2_ALLOC_OPT_LOCK_NOLOCK);
 	if (caching_topic == NULL) {
 		return NULL;
 	}
 
-	caching_topic->cache = ao2_container_alloc(NUM_CACHE_BUCKETS, cache_entry_hash, cache_entry_cmp);
-	if (!caching_topic->cache) {
-		ast_log(LOG_ERROR, "Stasis cache allocation failed\n");
-		return NULL;
-	}
-
 	caching_topic->topic = stasis_topic_create(new_name);
 	if (caching_topic->topic == NULL) {
 		return NULL;
 	}
 
-	caching_topic->id_fn = id_fn;
+	ao2_ref(cache, +1);
+	caching_topic->cache = cache;
 
 	sub = internal_stasis_subscribe(original_topic, caching_topic_exec, caching_topic, 0);
 	if (sub == NULL) {
@@ -514,7 +490,6 @@ static void stasis_cache_cleanup(void)
 {
 	STASIS_MESSAGE_TYPE_CLEANUP(stasis_cache_clear_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(stasis_cache_update_type);
-	STASIS_MESSAGE_TYPE_CLEANUP(cache_guarantee_type);
 }
 
 int stasis_cache_init(void)
@@ -529,10 +504,6 @@ int stasis_cache_init(void)
 		return -1;
 	}
 
-	if (STASIS_MESSAGE_TYPE_INIT(cache_guarantee_type) != 0) {
-		return -1;
-	}
-
 	return 0;
 }
 

main/stasis_cache_pattern.c

@@ -0,0 +1,189 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * David M. Lee, II <dlee@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief Typical cache pattern for Stasis topics.
+ *
+ * \author David M. Lee, II <dlee@digium.com>
+ */
+
+/*** MODULEINFO
+	<support_level>core</support_level>
+ ***/
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
+
+#include "asterisk/astobj2.h"
+#include "asterisk/stasis_cache_pattern.h"
+
+struct stasis_cp_all {
+	struct stasis_topic *topic;
+	struct stasis_topic *topic_cached;
+	struct stasis_cache *cache;
+};
+
+struct stasis_cp_single {
+	struct stasis_topic *topic;
+	struct stasis_caching_topic *topic_cached;
+
+	struct stasis_subscription *forward;
+	struct stasis_subscription *forward_cached;
+};
+
+static void all_dtor(void *obj)
+{
+	struct stasis_cp_all *all = obj;
+
+	ao2_cleanup(all->topic);
+	ao2_cleanup(all->topic_cached);
+	ao2_cleanup(all->cache);
+}
+
+struct stasis_cp_all *stasis_cp_all_create(const char *name,
+	snapshot_get_id id_fn)
+{
+	RAII_VAR(char *, cached_name, NULL, ast_free);
+	RAII_VAR(struct stasis_cp_all *, all, NULL, ao2_cleanup);
+
+	all = ao2_alloc(sizeof(*all), all_dtor);
+	if (!all) {
+		return NULL;
+	}
+
+	ast_asprintf(&cached_name, "%s-cached", name);
+	if (!cached_name) {
+		return NULL;
+	}
+
+	all->topic = stasis_topic_create(name);
+	all->topic_cached = stasis_topic_create(cached_name);
+	all->cache = stasis_cache_create(id_fn);
+
+	if (!all->topic || !all->topic_cached || !all->cache) {
+		return NULL;
+	}
+
+	ao2_ref(all, +1);
+	return all;
+}
+
+struct stasis_topic *stasis_cp_all_topic(struct stasis_cp_all *all)
+{
+	if (!all) {
+		return NULL;
+	}
+	return all->topic;
+}
+
+struct stasis_topic *stasis_cp_all_topic_cached(
+	struct stasis_cp_all *all)
+{
+	if (!all) {
+		return NULL;
+	}
+	return all->topic_cached;
+}
+
+struct stasis_cache *stasis_cp_all_cache(struct stasis_cp_all *all)
+{
+	if (!all) {
+		return NULL;
+	}
+	return all->cache;
+}
+
+static void one_dtor(void *obj)
+{
+	struct stasis_cp_single *one = obj;
+
+	/* Should already be unsubscribed */
+	ast_assert(one->topic_cached == NULL);
+	ast_assert(one->forward == NULL);
+	ast_assert(one->forward_cached == NULL);
+
+	ao2_cleanup(one->topic);
+	one->topic = NULL;
+}
+
+struct stasis_cp_single *stasis_cp_single_create(struct stasis_cp_all *all,
+	const char *name)
+{
+	RAII_VAR(struct stasis_cp_single *, one, NULL, ao2_cleanup);
+
+	one = ao2_alloc(sizeof(*one), one_dtor);
+	if (!one) {
+		return NULL;
+	}
+
+	one->topic = stasis_topic_create(name);
+	if (!one->topic) {
+		return NULL;
+	}
+	one->topic_cached = stasis_caching_topic_create(one->topic, all->cache);
+	if (!one->topic_cached) {
+		return NULL;
+	}
+
+	one->forward = stasis_forward_all(one->topic, all->topic);
+	if (!one->forward) {
+		return NULL;
+	}
+	one->forward_cached = stasis_forward_all(
+		stasis_caching_get_topic(one->topic_cached), all->topic_cached);
+	if (!one->forward_cached) {
+		return NULL;
+	}
+
+	ao2_ref(one, +1);
+	return one;
+}
+
+void stasis_cp_single_unsubscribe(struct stasis_cp_single *one)
+{
+	if (!one) {
+		return;
+	}
+
+	stasis_caching_unsubscribe(one->topic_cached);
+	one->topic_cached = NULL;
+	stasis_unsubscribe(one->forward);
+	one->forward = NULL;
+	stasis_unsubscribe(one->forward_cached);
+	one->forward_cached = NULL;
+}
+
+struct stasis_topic *stasis_cp_single_topic(struct stasis_cp_single *one)
+{
+	if (!one) {
+		return NULL;
+	}
+	return one->topic;
+}
+
+struct stasis_topic *stasis_cp_single_topic_cached(
+	struct stasis_cp_single *one)
+{
+	if (!one) {
+		return NULL;
+	}
+	return stasis_caching_get_topic(one->topic_cached);
+}
+

main/stasis_channels.c

@@ -38,6 +38,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/bridge.h"
 #include "asterisk/translate.h"
 #include "asterisk/stasis.h"
+#include "asterisk/stasis_cache_pattern.h"
 #include "asterisk/stasis_channels.h"
 
 /*** DOCUMENTATION
@@ -88,23 +89,33 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 
 #define NUM_MULTI_CHANNEL_BLOB_BUCKETS 7
 
-/*! \brief Topic for all channels */
+static struct stasis_cp_all *channel_cache_all;
-struct stasis_topic *channel_topic_all;
+static struct stasis_cache *channel_cache_by_name;
+static struct stasis_caching_topic *channel_by_name_topic;
 
-/*! \brief Caching topic for all channels */
+struct stasis_cp_all *ast_channel_cache_all(void)
-struct stasis_caching_topic *channel_topic_all_cached;
+{
+	return channel_cache_all;
+}
 
-/*! \brief Caching topic for all channels indexed by name */
+struct stasis_cache *ast_channel_cache(void)
-struct stasis_caching_topic *channel_topic_all_cached_by_name;
+{
+	return stasis_cp_all_cache(channel_cache_all);
+}
 
 struct stasis_topic *ast_channel_topic_all(void)
 {
-	return channel_topic_all;
+	return stasis_cp_all_topic(channel_cache_all);
 }
 
-struct stasis_caching_topic *ast_channel_topic_all_cached(void)
+struct stasis_topic *ast_channel_topic_all_cached(void)
 {
-	return channel_topic_all_cached;
+	return stasis_cp_all_topic_cached(channel_cache_all);
+}
+
+struct stasis_cache *ast_channel_cache_by_name(void)
+{
+	return channel_cache_by_name;
 }
 
 static const char *channel_snapshot_get_id(struct stasis_message *message)
@@ -117,11 +128,6 @@ static const char *channel_snapshot_get_id(struct stasis_message *message)
 	return snapshot->uniqueid;
 }
 
-struct stasis_caching_topic *ast_channel_topic_all_cached_by_name(void)
-{
-	return channel_topic_all_cached_by_name;
-}
-
 static const char *channel_snapshot_get_name(struct stasis_message *message)
 {
 	struct ast_channel_snapshot *snapshot;
@@ -461,7 +467,7 @@ struct ast_channel_snapshot *ast_channel_snapshot_get_latest(const char *uniquei
 
 	ast_assert(!ast_strlen_zero(uniqueid));
 
-	message = stasis_cache_get(ast_channel_topic_all_cached(),
+	message = stasis_cache_get(ast_channel_cache(),
 			ast_channel_snapshot_type(),
 			uniqueid);
 	if (!message) {
@@ -483,7 +489,7 @@ struct ast_channel_snapshot *ast_channel_snapshot_get_latest_by_name(const char
 
 	ast_assert(!ast_strlen_zero(name));
 
-	message = stasis_cache_get(ast_channel_topic_all_cached_by_name(),
+	message = stasis_cache_get(ast_channel_cache_by_name(),
 			ast_channel_snapshot_type(),
 			name);
 	if (!message) {
@@ -906,10 +912,6 @@ STASIS_MESSAGE_TYPE_DEFN(ast_channel_agent_logoff_type,
 
 static void stasis_channels_cleanup(void)
 {
-	channel_topic_all_cached = stasis_caching_unsubscribe_and_join(channel_topic_all_cached);
-	channel_topic_all_cached_by_name = stasis_caching_unsubscribe_and_join(channel_topic_all_cached_by_name);
-	ao2_cleanup(channel_topic_all);
-	channel_topic_all = NULL;
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_snapshot_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_dial_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_varset_type);
@@ -929,33 +931,58 @@ static void stasis_channels_cleanup(void)
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_monitor_stop_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_agent_login_type);
 	STASIS_MESSAGE_TYPE_CLEANUP(ast_channel_agent_logoff_type);
+
+	stasis_caching_unsubscribe_and_join(channel_by_name_topic);
+	channel_by_name_topic = NULL;
+	ao2_cleanup(channel_cache_by_name);
+	channel_cache_by_name = NULL;
+	ao2_cleanup(channel_cache_all);
+	channel_cache_all = NULL;
 }
 
-void ast_stasis_channels_init(void)
+int ast_stasis_channels_init(void)
 {
+	int res = 0;
+
 	ast_register_cleanup(stasis_channels_cleanup);
 
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_snapshot_type);
+	channel_cache_all = stasis_cp_all_create("ast_channel_topic_all",
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_dial_type);
+		channel_snapshot_get_id);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_varset_type);
+	if (!channel_cache_all) {
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_user_event_type);
+		return -1;
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_hangup_request_type);
+	}
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_dtmf_begin_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_dtmf_end_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_hold_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_unhold_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_chanspy_start_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_chanspy_stop_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_fax_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_hangup_handler_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_moh_start_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_moh_stop_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_monitor_start_type);
-	STASIS_MESSAGE_TYPE_INIT(ast_channel_monitor_stop_type);
 	STASIS_MESSAGE_TYPE_INIT(ast_channel_agent_login_type);
 	STASIS_MESSAGE_TYPE_INIT(ast_channel_agent_logoff_type);
 
-	channel_topic_all = stasis_topic_create("ast_channel_topic_all");
+	channel_cache_by_name = stasis_cache_create(channel_snapshot_get_name);
-	channel_topic_all_cached = stasis_caching_topic_create(channel_topic_all, channel_snapshot_get_id);
+	if (!channel_cache_by_name) {
-	channel_topic_all_cached_by_name = stasis_caching_topic_create(channel_topic_all, channel_snapshot_get_name);
+		return -1;
+	}
+
+	channel_by_name_topic = stasis_caching_topic_create(
+		stasis_cp_all_topic(channel_cache_all),
+		channel_cache_by_name);
+	if (!channel_by_name_topic) {
+		return -1;
+	}
+
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_snapshot_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_dial_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_varset_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_user_event_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_hangup_request_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_dtmf_begin_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_dtmf_end_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_hold_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_unhold_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_chanspy_start_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_chanspy_stop_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_fax_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_hangup_handler_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_moh_start_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_moh_stop_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_monitor_start_type);
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_channel_monitor_stop_type);
+
+	return res;
 }

main/stasis_endpoints.c

@@ -73,6 +73,28 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 	</managerEvent>
 ***/
 
+static struct stasis_cp_all *endpoint_cache_all;
+
+struct stasis_cp_all *ast_endpoint_cache_all(void)
+{
+	return endpoint_cache_all;
+}
+
+struct stasis_cache *ast_endpoint_cache(void)
+{
+	return stasis_cp_all_cache(endpoint_cache_all);
+}
+
+struct stasis_topic *ast_endpoint_topic_all(void)
+{
+	return stasis_cp_all_topic(endpoint_cache_all);
+}
+
+struct stasis_topic *ast_endpoint_topic_all_cached(void)
+{
+	return stasis_cp_all_topic_cached(endpoint_cache_all);
+}
+
 static struct ast_manager_event_blob *peerstatus_to_ami(struct stasis_message *msg);
 
 STASIS_MESSAGE_TYPE_DEFN(ast_endpoint_snapshot_type);
@@ -80,10 +102,6 @@ STASIS_MESSAGE_TYPE_DEFN(ast_endpoint_state_type,
 	.to_ami = peerstatus_to_ami,
 );
 
-static struct stasis_topic *endpoint_topic_all;
-
-static struct stasis_caching_topic *endpoint_topic_all_cached;
-
 static struct ast_manager_event_blob *peerstatus_to_ami(struct stasis_message *msg)
 {
 	struct ast_endpoint_blob *obj = stasis_message_data(msg);
@@ -168,16 +186,6 @@ void ast_endpoint_blob_publish(struct ast_endpoint *endpoint, struct stasis_mess
 	}
 }
 
-struct stasis_topic *ast_endpoint_topic_all(void)
-{
-	return endpoint_topic_all;
-}
-
-struct stasis_caching_topic *ast_endpoint_topic_all_cached(void)
-{
-	return endpoint_topic_all_cached;
-}
-
 struct ast_endpoint_snapshot *ast_endpoint_latest_snapshot(const char *tech,
 	const char *name, unsigned int guaranteed)
 {
@@ -190,8 +198,12 @@ struct ast_endpoint_snapshot *ast_endpoint_latest_snapshot(const char *tech,
 		return NULL;
 	}
 
-	msg = stasis_cache_get_extended(ast_endpoint_topic_all_cached(),
+	if (guaranteed) {
-		ast_endpoint_snapshot_type(), id, guaranteed);
+		stasis_topic_wait(ast_endpoint_topic_all_cached());
+	}
+
+	msg = stasis_cache_get(ast_endpoint_cache(),
+		ast_endpoint_snapshot_type(), id);
 	if (!msg) {
 		return NULL;
 	}
@@ -267,44 +279,28 @@ struct ast_json *ast_endpoint_snapshot_to_json(
 	return ast_json_ref(json);
 }
 
-static void endpoints_stasis_shutdown(void)
+static void endpoints_stasis_cleanup(void)
 {
-	stasis_caching_unsubscribe_and_join(endpoint_topic_all_cached);
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_endpoint_snapshot_type);
-	endpoint_topic_all_cached = NULL;
+	STASIS_MESSAGE_TYPE_CLEANUP(ast_endpoint_state_type);
 
-	ao2_cleanup(endpoint_topic_all);
+	ao2_cleanup(endpoint_cache_all);
-	endpoint_topic_all = NULL;
+	endpoint_cache_all = NULL;
 }
 
 int ast_endpoint_stasis_init(void)
 {
-	ast_register_atexit(endpoints_stasis_shutdown);
+	int res = 0;
+	ast_register_cleanup(endpoints_stasis_cleanup);
 
-	if (STASIS_MESSAGE_TYPE_INIT(ast_endpoint_snapshot_type) != 0) {
+	endpoint_cache_all = stasis_cp_all_create("endpoint_topic_all",
+		endpoint_snapshot_get_id);
+	if (!endpoint_cache_all) {
 		return -1;
 	}
 
-	if (!endpoint_topic_all) {
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_endpoint_snapshot_type);
-		endpoint_topic_all = stasis_topic_create("endpoint_topic_all");
+	res |= STASIS_MESSAGE_TYPE_INIT(ast_endpoint_state_type);
-	}
 
-	if (!endpoint_topic_all) {
+	return res;
-		return -1;
-	}
-
-	if (!endpoint_topic_all_cached) {
-		endpoint_topic_all_cached =
-			stasis_caching_topic_create(
-				endpoint_topic_all, endpoint_snapshot_get_id);
-	}
-
-	if (!endpoint_topic_all_cached) {
-		return -1;
-	}
-
-	if (STASIS_MESSAGE_TYPE_INIT(ast_endpoint_state_type) != 0) {
-		return -1;
-	}
-
-	return 0;
 }

main/stasis_wait.c

@@ -0,0 +1,133 @@
+/*
+ * Asterisk -- An open source telephony toolkit.
+ *
+ * Copyright (C) 2013, Digium, Inc.
+ *
+ * Joshua Colp <jcolp@digium.com>
+ *
+ * See http://www.asterisk.org for more information about
+ * the Asterisk project. Please do not directly contact
+ * any of the maintainers of this project for assistance;
+ * the project provides a web site, mailing lists and IRC
+ * channels for your use.
+ *
+ * This program is free software, distributed under the terms of
+ * the GNU General Public License Version 2. See the LICENSE file
+ * at the top of the source tree.
+ */
+
+/*! \file
+ *
+ * \brief Wait support for Stasis topics.
+ *
+ * \author Joshua Colp <jcolp@digium.com>
+ */
+
+/*** MODULEINFO
+	<support_level>core</support_level>
+ ***/
+
+#include "asterisk.h"
+
+ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
+
+#include "asterisk/astobj2.h"
+#include "asterisk/stasis.h"
+
+static struct stasis_message_type *cache_guarantee_type(void);
+STASIS_MESSAGE_TYPE_DEFN(cache_guarantee_type);
+
+/*! \internal */
+struct caching_guarantee {
+	ast_mutex_t lock;
+	ast_cond_t cond;
+	unsigned int done:1;
+};
+
+static void caching_guarantee_dtor(void *obj)
+{
+	struct caching_guarantee *guarantee = obj;
+
+	ast_assert(guarantee->done == 1);
+
+	ast_mutex_destroy(&guarantee->lock);
+	ast_cond_destroy(&guarantee->cond);
+}
+
+static void guarantee_handler(void *data, struct stasis_subscription *sub,
+	struct stasis_topic *topic, struct stasis_message *message)
+{
+	/* Wait for our particular message */
+	if (data == message) {
+		struct caching_guarantee *guarantee;
+		ast_assert(cache_guarantee_type() == stasis_message_type(message));
+		guarantee = stasis_message_data(message);
+
+		ast_mutex_lock(&guarantee->lock);
+		guarantee->done = 1;
+		ast_cond_signal(&guarantee->cond);
+		ast_mutex_unlock(&guarantee->lock);
+	}
+}
+
+static struct stasis_message *caching_guarantee_create(void)
+{
+	RAII_VAR(struct caching_guarantee *, guarantee, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+
+	if (!(guarantee = ao2_alloc(sizeof(*guarantee), caching_guarantee_dtor))) {
+		return NULL;
+	}
+
+	ast_mutex_init(&guarantee->lock);
+	ast_cond_init(&guarantee->cond, NULL);
+
+	if (!(msg = stasis_message_create(cache_guarantee_type(), guarantee))) {
+		return NULL;
+	}
+
+	ao2_ref(msg, +1);
+	return msg;
+}
+
+int stasis_topic_wait(struct stasis_topic *topic)
+{
+	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_subscription *, sub, NULL, stasis_unsubscribe);
+	struct caching_guarantee *guarantee;
+
+	msg = caching_guarantee_create();
+	if (!msg) {
+		return -1;
+	}
+
+	sub = stasis_subscribe(topic, guarantee_handler, msg);
+	if (!sub) {
+		return -1;
+	}
+
+	guarantee = stasis_message_data(msg);
+
+	ast_mutex_lock(&guarantee->lock);
+	stasis_publish(topic, msg);
+	while (!guarantee->done) {
+		ast_cond_wait(&guarantee->cond, &guarantee->lock);
+	}
+	ast_mutex_unlock(&guarantee->lock);
+	return 0;
+}
+
+static void wait_cleanup(void)
+{
+	STASIS_MESSAGE_TYPE_CLEANUP(cache_guarantee_type);
+}
+
+int stasis_wait_init(void)
+{
+	ast_register_cleanup(wait_cleanup);
+
+	if (STASIS_MESSAGE_TYPE_INIT(cache_guarantee_type) != 0) {
+		return -1;
+	}
+	return 0;
+}

res/ari/resource_bridges.c

@@ -448,22 +448,22 @@ void ast_ari_delete_bridge(struct ast_variable *headers, struct ast_delete_bridg
 
 void ast_ari_get_bridges(struct ast_variable *headers, struct ast_get_bridges_args *args, struct ast_ari_response *response)
 {
-	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct ao2_container *, snapshots, NULL, ao2_cleanup);
 	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
 	struct ao2_iterator i;
 	void *obj;
 
-	caching_topic = ast_bridge_topic_all_cached();
+	cache = ast_bridge_cache();
-	if (!caching_topic) {
+	if (!cache) {
 		ast_ari_response_error(
 			response, 500, "Internal Server Error",
 			"Message bus not initialized");
 		return;
 	}
-	ao2_ref(caching_topic, +1);
+	ao2_ref(cache, +1);
 
-	snapshots = stasis_cache_dump(caching_topic, ast_bridge_snapshot_type());
+	snapshots = stasis_cache_dump(cache, ast_bridge_snapshot_type());
 	if (!snapshots) {
 		ast_ari_response_alloc_failed(response);
 		return;

res/ari/resource_channels.c

@@ -466,18 +466,18 @@ void ast_ari_get_channel(struct ast_variable *headers,
 			     struct ast_ari_response *response)
 {
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
-	struct stasis_caching_topic *caching_topic;
+	struct stasis_cache *cache;
 	struct ast_channel_snapshot *snapshot;
 
-	caching_topic = ast_channel_topic_all_cached();
+	cache = ast_channel_cache();
-	if (!caching_topic) {
+	if (!cache) {
 		ast_ari_response_error(
 			response, 500, "Internal Server Error",
 			"Message bus not initialized");
 		return;
 	}
 
-	msg = stasis_cache_get(caching_topic, ast_channel_snapshot_type(),
+	msg = stasis_cache_get(cache, ast_channel_snapshot_type(),
 			       args->channel_id);
 	if (!msg) {
 		ast_ari_response_error(
@@ -516,22 +516,22 @@ void ast_ari_get_channels(struct ast_variable *headers,
 			      struct ast_get_channels_args *args,
 			      struct ast_ari_response *response)
 {
-	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct ao2_container *, snapshots, NULL, ao2_cleanup);
 	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
 	struct ao2_iterator i;
 	void *obj;
 
-	caching_topic = ast_channel_topic_all_cached();
+	cache = ast_channel_cache();
-	if (!caching_topic) {
+	if (!cache) {
 		ast_ari_response_error(
 			response, 500, "Internal Server Error",
 			"Message bus not initialized");
 		return;
 	}
-	ao2_ref(caching_topic, +1);
+	ao2_ref(cache, +1);
 
-	snapshots = stasis_cache_dump(caching_topic, ast_channel_snapshot_type());
+	snapshots = stasis_cache_dump(cache, ast_channel_snapshot_type());
 	if (!snapshots) {
 		ast_ari_response_alloc_failed(response);
 		return;

res/ari/resource_endpoints.c

@@ -37,22 +37,22 @@ void ast_ari_get_endpoints(struct ast_variable *headers,
 	struct ast_get_endpoints_args *args,
 	struct ast_ari_response *response)
 {
-	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct ao2_container *, snapshots, NULL, ao2_cleanup);
 	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
 	struct ao2_iterator i;
 	void *obj;
 
-	caching_topic = ast_endpoint_topic_all_cached();
+	cache = ast_endpoint_cache();
-	if (!caching_topic) {
+	if (!cache) {
 		ast_ari_response_error(
 			response, 500, "Internal Server Error",
 			"Message bus not initialized");
 		return;
 	}
-	ao2_ref(caching_topic, +1);
+	ao2_ref(cache, +1);
 
-	snapshots = stasis_cache_dump(caching_topic, ast_endpoint_snapshot_type());
+	snapshots = stasis_cache_dump(cache, ast_endpoint_snapshot_type());
 	if (!snapshots) {
 		ast_ari_response_alloc_failed(response);
 		return;
@@ -83,7 +83,7 @@ void ast_ari_get_endpoints_by_tech(struct ast_variable *headers,
 	struct ast_get_endpoints_by_tech_args *args,
 	struct ast_ari_response *response)
 {
-	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct ao2_container *, snapshots, NULL, ao2_cleanup);
 	RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
 	struct ao2_iterator i;
@@ -91,16 +91,16 @@ void ast_ari_get_endpoints_by_tech(struct ast_variable *headers,
 
 	/* TODO - if tech isn't a recognized type of endpoint, it should 404 */
 
-	caching_topic = ast_endpoint_topic_all_cached();
+	cache = ast_endpoint_cache();
-	if (!caching_topic) {
+	if (!cache) {
 		ast_ari_response_error(
 			response, 500, "Internal Server Error",
 			"Message bus not initialized");
 		return;
 	}
-	ao2_ref(caching_topic, +1);
+	ao2_ref(cache, +1);
 
-	snapshots = stasis_cache_dump(caching_topic, ast_endpoint_snapshot_type());
+	snapshots = stasis_cache_dump(cache, ast_endpoint_snapshot_type());
 	if (!snapshots) {
 		ast_ari_response_alloc_failed(response);
 		return;

res/res_agi.c

@@ -2771,7 +2771,7 @@ static int handle_channelstatus(struct ast_channel *chan, AGI *agi, int argc, co
 		RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
 
 		/* one argument: look for info on the specified channel */
-		if ((msg = stasis_cache_get(ast_channel_topic_all_cached_by_name(), ast_channel_snapshot_type(), argv[2]))) {
+		if ((msg = stasis_cache_get(ast_channel_cache_by_name(), ast_channel_snapshot_type(), argv[2]))) {
 			struct ast_channel_snapshot *snapshot = stasis_message_data(msg);
 
 			ast_agi_send(agi->fd, chan, "200 result=%d\n", snapshot->state);

res/res_chan_stats.c

@@ -154,7 +154,7 @@ static int load_module(void)
 {
 	/* You can create a message router to route messages by type */
 	router = stasis_message_router_create(
-		stasis_caching_get_topic(ast_channel_topic_all_cached()));
+		ast_channel_topic_all_cached());
 	if (!router) {
 		return AST_MODULE_LOAD_FAILURE;
 	}

res/res_jabber.c

@@ -3310,7 +3310,7 @@ static void aji_init_event_distribution(struct aji_client *client)
 		RAII_VAR(struct ao2_container *, cached, NULL, ao2_cleanup);
 		device_state_sub = stasis_subscribe(ast_device_state_topic_all(),
 			aji_devstate_cb, client);
-		cached = stasis_cache_dump(ast_device_state_topic_cached(), NULL);
+		cached = stasis_cache_dump(ast_device_state_cache(), NULL);
 		ao2_callback(cached, OBJ_NODATA, cached_devstate_cb, client);
 	}
 

res/res_stasis.c

@@ -993,7 +993,7 @@ static int load_module(void)
 		return AST_MODULE_LOAD_FAILURE;
 	}
 
-	channel_router = stasis_message_router_create(stasis_caching_get_topic(ast_channel_topic_all_cached()));
+	channel_router = stasis_message_router_create(ast_channel_topic_all_cached());
 	if (!channel_router) {
 		return AST_MODULE_LOAD_FAILURE;
 	}
@@ -1013,7 +1013,7 @@ static int load_module(void)
 		return AST_MODULE_LOAD_FAILURE;
 	}
 
-	bridge_router = stasis_message_router_create(stasis_caching_get_topic(ast_bridge_topic_all_cached()));
+	bridge_router = stasis_message_router_create(ast_bridge_topic_all_cached());
 	if (!bridge_router) {
 		return AST_MODULE_LOAD_FAILURE;
 	}

res/res_xmpp.c

@@ -1605,7 +1605,7 @@ static void xmpp_init_event_distribution(struct ast_xmpp_client *client)
 		return;
 	}
 
-	cached = stasis_cache_dump(ast_device_state_topic_cached(), NULL);
+	cached = stasis_cache_dump(ast_device_state_cache(), NULL);
 	ao2_callback(cached, OBJ_NODATA, cached_devstate_cb, client);
 
 	xmpp_pubsub_subscribe(client, "device_state");

res/stasis/control.c

@@ -364,13 +364,9 @@ struct ast_channel_snapshot *stasis_app_control_get_snapshot(
 	const struct stasis_app_control *control)
 {
 	RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
-	struct stasis_caching_topic *caching_topic;
 	struct ast_channel_snapshot *snapshot;
 
-	caching_topic = ast_channel_topic_all_cached();
+	msg = stasis_cache_get(ast_channel_cache(), ast_channel_snapshot_type(),
-	ast_assert(caching_topic != NULL);
-
-	msg = stasis_cache_get(caching_topic, ast_channel_snapshot_type(),
 		stasis_app_control_get_channel_id(control));
 	if (!msg) {
 		return NULL;

tests/test_cel.c

@@ -224,8 +224,9 @@ static void do_sleep(void)
 	ast_hangup((channel)); \
 	HANGUP_EVENT(channel, cause, dialstatus); \
 	APPEND_EVENT(channel, AST_CEL_CHANNEL_END, NULL, NULL, NULL); \
-	ao2_cleanup(stasis_cache_get_extended(ast_channel_topic_all_cached(), \
+	stasis_topic_wait(ast_channel_topic_all_cached()); \
-		ast_channel_snapshot_type(), ast_channel_uniqueid(channel), 1)); \
+	ao2_cleanup(stasis_cache_get(ast_channel_cache(), \
+		ast_channel_snapshot_type(), ast_channel_uniqueid(channel))); \
 	ao2_cleanup(channel); \
 	channel = NULL; \
 	} while (0)

tests/test_devicestate.c

@@ -394,7 +394,7 @@ static void cache_cleanup(int unused)
 {
 	RAII_VAR(struct ao2_container *, cache_dump, NULL, ao2_cleanup);
 	/* remove all device states created during this test */
-	cache_dump = stasis_cache_dump(ast_device_state_topic_cached(), NULL);
+	cache_dump = stasis_cache_dump(ast_device_state_cache(), NULL);
 	if (!cache_dump) {
 		return;
 	}
@@ -434,7 +434,7 @@ AST_TEST_DEFINE(device_state_aggregation_test)
 	consumer = consumer_create();
 	ast_test_validate(test, NULL != consumer);
 
-	device_msg_router = stasis_message_router_create(stasis_caching_get_topic(ast_device_state_topic_cached()));
+	device_msg_router = stasis_message_router_create(ast_device_state_topic_cached());
 	ast_test_validate(test, NULL != device_msg_router);
 
 	ao2_ref(consumer, +1);
@@ -451,7 +451,7 @@ AST_TEST_DEFINE(device_state_aggregation_test)
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == consumer->state);
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == consumer->aggregate_state);
 
-	msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
+	msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
 	device_state = stasis_message_data(msg);
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == device_state->state);
 	ao2_cleanup(msg);
@@ -466,7 +466,7 @@ AST_TEST_DEFINE(device_state_aggregation_test)
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == consumer->state);
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == consumer->aggregate_state);
 
-	msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
+	msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
 	device_state = stasis_message_data(msg);
 	ast_test_validate(test, AST_DEVICE_NOT_INUSE == device_state->state);
 	ao2_cleanup(msg);
@@ -479,7 +479,7 @@ AST_TEST_DEFINE(device_state_aggregation_test)
 	ast_test_validate(test, AST_DEVICE_INUSE == consumer->state);
 	ast_test_validate(test, AST_DEVICE_INUSE == consumer->aggregate_state);
 
-	msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
+	msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
 	device_state = stasis_message_data(msg);
 	ast_test_validate(test, AST_DEVICE_INUSE == device_state->state);
 	ao2_cleanup(msg);
@@ -492,7 +492,7 @@ AST_TEST_DEFINE(device_state_aggregation_test)
 	ast_test_validate(test, AST_DEVICE_RINGING == consumer->state);
 	ast_test_validate(test, AST_DEVICE_RINGINUSE == consumer->aggregate_state);
 
-	msg = stasis_cache_get(ast_device_state_topic_cached(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
+	msg = stasis_cache_get(ast_device_state_cache(), ast_device_state_message_type(), UNIT_TEST_DEVICE_IDENTIFIER);
 	device_state = stasis_message_data(msg);
 	ast_test_validate(test, AST_DEVICE_RINGINUSE == device_state->state);
 	ao2_cleanup(msg);

tests/test_stasis.c

@@ -614,6 +614,7 @@ AST_TEST_DEFINE(cache_passthrough)
 {
 	RAII_VAR(struct stasis_message_type *, non_cache_type, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_topic *, topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, stasis_caching_unsubscribe);
 	RAII_VAR(struct consumer *, consumer, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_subscription *, sub, NULL, stasis_unsubscribe);
@@ -636,7 +637,9 @@ AST_TEST_DEFINE(cache_passthrough)
 	ast_test_validate(test, NULL != non_cache_type);
 	topic = stasis_topic_create("SomeTopic");
 	ast_test_validate(test, NULL != topic);
-	caching_topic = stasis_caching_topic_create(topic, cache_test_data_id);
+	cache = stasis_cache_create(cache_test_data_id);
+	ast_test_validate(test, NULL != cache);
+	caching_topic = stasis_caching_topic_create(topic, cache);
 	ast_test_validate(test, NULL != caching_topic);
 	consumer = consumer_create(1);
 	ast_test_validate(test, NULL != consumer);
@@ -664,6 +667,7 @@ AST_TEST_DEFINE(cache)
 {
 	RAII_VAR(struct stasis_message_type *, cache_type, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_topic *, topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, stasis_caching_unsubscribe);
 	RAII_VAR(struct consumer *, consumer, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_subscription *, sub, NULL, stasis_unsubscribe);
@@ -689,7 +693,9 @@ AST_TEST_DEFINE(cache)
 	ast_test_validate(test, NULL != cache_type);
 	topic = stasis_topic_create("SomeTopic");
 	ast_test_validate(test, NULL != topic);
-	caching_topic = stasis_caching_topic_create(topic, cache_test_data_id);
+	cache = stasis_cache_create(cache_test_data_id);
+	ast_test_validate(test, NULL != cache);
+	caching_topic = stasis_caching_topic_create(topic, cache);
 	ast_test_validate(test, NULL != caching_topic);
 	consumer = consumer_create(1);
 	ast_test_validate(test, NULL != consumer);
@@ -714,7 +720,7 @@ AST_TEST_DEFINE(cache)
 	ast_test_validate(test, topic == actual_update->topic);
 	ast_test_validate(test, NULL == actual_update->old_snapshot);
 	ast_test_validate(test, test_message1_1 == actual_update->new_snapshot);
-	ast_test_validate(test, test_message1_1 == stasis_cache_get(caching_topic, cache_type, "1"));
+	ast_test_validate(test, test_message1_1 == stasis_cache_get(cache, cache_type, "1"));
 	/* stasis_cache_get returned a ref, so unref test_message1_1 */
 	ao2_ref(test_message1_1, -1);
 
@@ -723,7 +729,7 @@ AST_TEST_DEFINE(cache)
 	ast_test_validate(test, topic == actual_update->topic);
 	ast_test_validate(test, NULL == actual_update->old_snapshot);
 	ast_test_validate(test, test_message2_1 == actual_update->new_snapshot);
-	ast_test_validate(test, test_message2_1 == stasis_cache_get(caching_topic, cache_type, "2"));
+	ast_test_validate(test, test_message2_1 == stasis_cache_get(cache, cache_type, "2"));
 	/* stasis_cache_get returned a ref, so unref test_message2_1 */
 	ao2_ref(test_message2_1, -1);
 
@@ -739,7 +745,7 @@ AST_TEST_DEFINE(cache)
 	ast_test_validate(test, topic == actual_update->topic);
 	ast_test_validate(test, test_message2_1 == actual_update->old_snapshot);
 	ast_test_validate(test, test_message2_2 == actual_update->new_snapshot);
-	ast_test_validate(test, test_message2_2 == stasis_cache_get(caching_topic, cache_type, "2"));
+	ast_test_validate(test, test_message2_2 == stasis_cache_get(cache, cache_type, "2"));
 	/* stasis_cache_get returned a ref, so unref test_message2_2 */
 	ao2_ref(test_message2_2, -1);
 
@@ -755,7 +761,7 @@ AST_TEST_DEFINE(cache)
 	ast_test_validate(test, topic == actual_update->topic);
 	ast_test_validate(test, test_message1_1 == actual_update->old_snapshot);
 	ast_test_validate(test, NULL == actual_update->new_snapshot);
-	ast_test_validate(test, NULL == stasis_cache_get(caching_topic, cache_type, "1"));
+	ast_test_validate(test, NULL == stasis_cache_get(cache, cache_type, "1"));
 
 	return AST_TEST_PASS;
 }
@@ -764,6 +770,7 @@ AST_TEST_DEFINE(cache_dump)
 {
 	RAII_VAR(struct stasis_message_type *, cache_type, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_topic *, topic, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, stasis_caching_unsubscribe);
 	RAII_VAR(struct consumer *, consumer, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_subscription *, sub, NULL, stasis_unsubscribe);
@@ -791,7 +798,9 @@ AST_TEST_DEFINE(cache_dump)
 	ast_test_validate(test, NULL != cache_type);
 	topic = stasis_topic_create("SomeTopic");
 	ast_test_validate(test, NULL != topic);
-	caching_topic = stasis_caching_topic_create(topic, cache_test_data_id);
+	cache = stasis_cache_create(cache_test_data_id);
+	ast_test_validate(test, NULL != cache);
+	caching_topic = stasis_caching_topic_create(topic, cache);
 	ast_test_validate(test, NULL != caching_topic);
 	consumer = consumer_create(1);
 	ast_test_validate(test, NULL != consumer);
@@ -811,7 +820,7 @@ AST_TEST_DEFINE(cache_dump)
 	ast_test_validate(test, 2 == actual_len);
 
 	/* Check the cache */
-	cache_dump = stasis_cache_dump(caching_topic, NULL);
+	cache_dump = stasis_cache_dump(cache, NULL);
 	ast_test_validate(test, NULL != cache_dump);
 	ast_test_validate(test, 2 == ao2_container_count(cache_dump));
 	i = ao2_iterator_init(cache_dump, 0);
@@ -829,7 +838,7 @@ AST_TEST_DEFINE(cache_dump)
 	ast_test_validate(test, 3 == actual_len);
 
 	/* Check the cache */
-	cache_dump = stasis_cache_dump(caching_topic, NULL);
+	cache_dump = stasis_cache_dump(cache, NULL);
 	ast_test_validate(test, NULL != cache_dump);
 	ast_test_validate(test, 2 == ao2_container_count(cache_dump));
 	i = ao2_iterator_init(cache_dump, 0);
@@ -847,7 +856,7 @@ AST_TEST_DEFINE(cache_dump)
 	ast_test_validate(test, 4 == actual_len);
 
 	/* Check the cache */
-	cache_dump = stasis_cache_dump(caching_topic, NULL);
+	cache_dump = stasis_cache_dump(cache, NULL);
 	ast_test_validate(test, NULL != cache_dump);
 	ast_test_validate(test, 1 == ao2_container_count(cache_dump));
 	i = ao2_iterator_init(cache_dump, 0);
@@ -858,7 +867,7 @@ AST_TEST_DEFINE(cache_dump)
 
 	/* Dump the cache to ensure that it has no subscription change items in it since those aren't cached */
 	ao2_cleanup(cache_dump);
-	cache_dump = stasis_cache_dump(caching_topic, stasis_subscription_change_type());
+	cache_dump = stasis_cache_dump(cache, stasis_subscription_change_type());
 	ast_test_validate(test, 0 == ao2_container_count(cache_dump));
 
 	return AST_TEST_PASS;
@@ -1019,7 +1028,8 @@ static const char *cache_simple(struct stasis_message *message) {
 AST_TEST_DEFINE(router_cache_updates)
 {
 	RAII_VAR(struct stasis_topic *, topic, NULL, ao2_cleanup);
-	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, stasis_caching_unsubscribe);
+	RAII_VAR(struct stasis_cache *, cache, NULL, ao2_cleanup);
+	RAII_VAR(struct stasis_caching_topic *, caching_topic, NULL, stasis_caching_unsubscribe_and_join);
 	RAII_VAR(struct stasis_message_type *, test_message_type1, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_message_type *, test_message_type2, NULL, ao2_cleanup);
 	RAII_VAR(struct stasis_message_type *, test_message_type3, NULL, ao2_cleanup);
@@ -1051,7 +1061,9 @@ AST_TEST_DEFINE(router_cache_updates)
 	topic = stasis_topic_create("TestTopic");
 	ast_test_validate(test, NULL != topic);
 
-	caching_topic = stasis_caching_topic_create(topic, cache_simple);
+	cache = stasis_cache_create(cache_simple);
+	ast_test_validate(test, NULL != cache);
+	caching_topic = stasis_caching_topic_create(topic, cache);
 	ast_test_validate(test, NULL != caching_topic);
 
 	consumer1 = consumer_create(1);

tests/test_stasis_endpoints.c

@@ -152,7 +152,7 @@ AST_TEST_DEFINE(cache_clear)
 	ast_test_validate(test, NULL != sink);
 
 	sub = stasis_subscribe(
-		stasis_caching_get_topic(ast_endpoint_topic_all_cached()),
+		ast_endpoint_topic_all_cached(),
 		stasis_message_sink_cb(), sink);
 	ast_test_validate(test, NULL != sub);