main/stasis_endpoints.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2013, Digium, Inc.
   5  *
   6  * David M. Lee, II <dlee@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*! \file
  20  *
  21  * \brief Stasis endpoint API.
  22  *
  23  * \author David M. Lee, II <dlee@digium.com>
  24  */
  25
  26 /*** MODULEINFO
  27         <support_level>core</support_level>
  28  ***/
  29
  30 #include "asterisk.h"
  31
  32 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  33
  34 #include "asterisk/astobj2.h"
  35 #include "asterisk/stasis.h"
  36 #include "asterisk/stasis_endpoints.h"
  37
  38 STASIS_MESSAGE_TYPE_DEFN(ast_endpoint_snapshot_type);
  39
  40 static struct stasis_topic *endpoint_topic_all;
  41
  42 static struct stasis_caching_topic *endpoint_topic_all_cached;
  43
  44 struct stasis_topic *ast_endpoint_topic_all(void)
  45 {
  46         return endpoint_topic_all;
  47 }
  48
  49 struct stasis_caching_topic *ast_endpoint_topic_all_cached(void)
  50 {
  51         return endpoint_topic_all_cached;
  52 }
  53
  54 struct ast_endpoint_snapshot *ast_endpoint_latest_snapshot(const char *tech,
  55         const char *name, unsigned int guaranteed)
  56 {
  57         RAII_VAR(char *, id, NULL, ast_free);
  58         RAII_VAR(struct stasis_message *, msg, NULL, ao2_cleanup);
  59         struct ast_endpoint_snapshot *snapshot;
  60
  61         ast_asprintf(&id, "%s/%s", tech, name);
  62         if (!id) {
  63                 return NULL;
  64         }
  65
  66         msg = stasis_cache_get_extended(ast_endpoint_topic_all_cached(),
  67                 ast_endpoint_snapshot_type(), id, guaranteed);
  68         if (!msg) {
  69                 return NULL;
  70         }
  71
  72         snapshot = stasis_message_data(msg);
  73         ast_assert(snapshot != NULL);
  74
  75         ao2_ref(snapshot, +1);
  76         return snapshot;
  77 }
  78
  79 /*!
  80  * \brief Callback extract a unique identity from a snapshot message.
  81  *
  82  * This identity is unique to the underlying object of the snapshot, such as the
  83  * UniqueId field of a channel.
  84  *
  85  * \param message Message to extract id from.
  86  * \return String representing the snapshot's id.
  87  * \return \c NULL if the message_type of the message isn't a handled snapshot.
  88  * \since 12
  89  */
  90 static const char *endpoint_snapshot_get_id(struct stasis_message *message)
  91 {
  92         struct ast_endpoint_snapshot *snapshot;
  93
  94         if (ast_endpoint_snapshot_type() != stasis_message_type(message)) {
  95                 return NULL;
  96         }
  97
  98         snapshot = stasis_message_data(message);
  99
 100         return snapshot->id;
 101 }
 102
 103
 104 struct ast_json *ast_endpoint_snapshot_to_json(
 105         const struct ast_endpoint_snapshot *snapshot)
 106 {
 107         RAII_VAR(struct ast_json *, json, NULL, ast_json_unref);
 108         struct ast_json *channel_array;
 109         int i;
 110
 111         json = ast_json_pack("{s: s, s: s, s: s, s: []}",
 112                 "technology", snapshot->tech,
 113                 "resource", snapshot->resource,
 114                 "state", ast_endpoint_state_to_string(snapshot->state),
 115                 "channels");
 116
 117         if (json == NULL) {
 118                 return NULL;
 119         }
 120
 121         if (snapshot->max_channels != -1) {
 122                 int res = ast_json_object_set(json, "max_channels",
 123                         ast_json_integer_create(snapshot->max_channels));
 124                 if (res != 0) {
 125                         return NULL;
 126                 }
 127         }
 128
 129         channel_array = ast_json_object_get(json, "channels");
 130         ast_assert(channel_array != NULL);
 131         for (i = 0; i < snapshot->num_channels; ++i) {
 132                 int res = ast_json_array_append(channel_array,
 133                         ast_json_stringf("channel:%s",
 134                                 snapshot->channel_ids[i]));
 135                 if (res != 0) {
 136                         return NULL;
 137                 }
 138         }
 139
 140         return ast_json_ref(json);
 141 }
 142
 143 static void endpoints_stasis_shutdown(void)
 144 {
 145         stasis_caching_unsubscribe_and_join(endpoint_topic_all_cached);
 146         endpoint_topic_all_cached = NULL;
 147
 148         ao2_cleanup(endpoint_topic_all);
 149         endpoint_topic_all = NULL;
 150 }
 151
 152 int ast_endpoint_stasis_init(void)
 153 {
 154         ast_register_atexit(endpoints_stasis_shutdown);
 155
 156         if (STASIS_MESSAGE_TYPE_INIT(ast_endpoint_snapshot_type) != 0) {
 157                 return -1;
 158         }
 159
 160         if (!endpoint_topic_all) {
 161                 endpoint_topic_all = stasis_topic_create("endpoint_topic_all");
 162         }
 163
 164         if (!endpoint_topic_all) {
 165                 return -1;
 166         }
 167
 168         if (!endpoint_topic_all_cached) {
 169                 endpoint_topic_all_cached =
 170                         stasis_caching_topic_create(
 171                                 endpoint_topic_all, endpoint_snapshot_get_id);
 172         }
 173
 174         if (!endpoint_topic_all_cached) {
 175                 return -1;
 176         }
 177
 178         return 0;
 179 }