asterisk/main/manager_endpoints.c
David M. Lee e1b959ccbb 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
2013-08-01 13:49:34 +00:00

95 lines
2.3 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2013, Digium, Inc.
*
* Joshua Colp <jcolp@digium.com>
* 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 The Asterisk Management Interface - AMI (endpoint handling)
*
* \author Joshua Colp <jcolp@digium.com>
* \author David M. Lee, II <dlee@digium.com>
*
*/
#include "asterisk.h"
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
#include "asterisk/callerid.h"
#include "asterisk/channel.h"
#include "asterisk/manager.h"
#include "asterisk/stasis_message_router.h"
#include "asterisk/pbx.h"
#include "asterisk/stasis_endpoints.h"
static struct stasis_message_router *endpoint_router;
static void manager_endpoints_shutdown(void)
{
stasis_message_router_unsubscribe_and_join(endpoint_router);
endpoint_router = NULL;
}
static void endpoint_state_cb(void *data, struct stasis_subscription *sub,
struct stasis_topic *topic,
struct stasis_message *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)
{
struct stasis_topic *endpoint_topic;
int ret = 0;
if (endpoint_router) {
/* Already initialized */
return 0;
}
ast_register_atexit(manager_endpoints_shutdown);
endpoint_topic = ast_endpoint_topic_all_cached();
if (!endpoint_topic) {
return -1;
}
endpoint_router = stasis_message_router_create(endpoint_topic);
if (!endpoint_router) {
return -1;
}
ret |= stasis_message_router_add(endpoint_router, ast_endpoint_state_type(), endpoint_state_cb, NULL);
/* If somehow we failed to add any routes, just shut down the whole
* thing and fail it.
*/
if (ret) {
manager_endpoints_shutdown();
return -1;
}
return 0;
}