Asterisk - The Open Source Telephony Project GIT-master-d856a3e
res_chan_stats.c
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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/*!
20 * \brief Statsd channel stats. Exmaple of how to subscribe to Stasis events.
21 *
22 * This module subscribes to the channel caching topic and issues statsd stats
23 * based on the received messages.
24 *
25 * \author David M. Lee, II <dlee@digium.com>
26 * \since 12
27 */
28
29/*** MODULEINFO
30 <depend>res_statsd</depend>
31 <defaultenabled>no</defaultenabled>
32 <support_level>extended</support_level>
33 ***/
34
35#include "asterisk.h"
36
37#include "asterisk/module.h"
40#include "asterisk/statsd.h"
41#include "asterisk/time.h"
42
43/*! Regular Stasis subscription */
44static struct stasis_subscription *sub;
45/*! Stasis message router */
47
48/*!
49 * \brief Subscription callback for all channel messages.
50 * \param data Data pointer given when creating the subscription.
51 * \param sub This subscription.
52 * \param message The message itself.
53 */
54static void statsmaker(void *data, struct stasis_subscription *sub,
55 struct stasis_message *message)
56{
57 RAII_VAR(struct ast_str *, metric, NULL, ast_free);
58
60 /* Normally, data points to an object that must be cleaned up.
61 * The final message is an unsubscribe notification that's
62 * guaranteed to be the last message this subscription receives.
63 * This would be a safe place to kick off any needed cleanup.
64 */
65 return;
66 }
67
68 /* For no good reason, count message types */
69 metric = ast_str_create(80);
70 if (metric) {
71 ast_str_set(&metric, 0, "stasis.message.%s",
74 }
75}
76
77/*!
78 * \brief Router callback for \ref ast_channel_snapshot_update messages.
79 * \param data Data pointer given when added to router.
80 * \param sub This subscription.
81 * \param message The message itself.
82 */
83static void updates(void *data, struct stasis_subscription *sub,
84 struct stasis_message *message)
85{
86 /* Since this came from a message router, we know the type of the
87 * message. We can cast the data without checking its type.
88 */
90
91 /* There are three types of channel snapshot updates.
92 * !old && new -> Initial channel creation
93 * old && new -> Updated channel snapshot
94 * old && dead -> Final channel snapshot
95 */
96
97 if (!update->old_snapshot && update->new_snapshot) {
98 /* Initial channel snapshot; count a channel creation */
99 ast_statsd_log_string("channels.count", AST_STATSD_GAUGE, "+1", 1.0);
100 } else if (update->old_snapshot && ast_test_flag(&update->new_snapshot->flags, AST_FLAG_DEAD)) {
101 /* Channel is gone. Compute the age of the channel and post
102 * that, as well as decrementing the channel count.
103 */
104 int64_t age;
105
107 update->new_snapshot->base->creationtime);
108 ast_statsd_log("channels.calltime", AST_STATSD_TIMER, age);
109
110 /* And decrement the channel count */
111 ast_statsd_log_string("channels.count", AST_STATSD_GAUGE, "-1", 1.0);
112 }
113}
114
115/*!
116 * \brief Router callback for any message that doesn't otherwise have a route.
117 * \param data Data pointer given when added to router.
118 * \param sub This subscription.
119 * \param message The message itself.
120 */
121static void default_route(void *data, struct stasis_subscription *sub,
122 struct stasis_message *message)
123{
125 /* Much like with the regular subscription, you may need to
126 * perform some cleanup when done with a message router. You
127 * can look for the final message in the default route.
128 */
129 return;
130 }
131}
132
133static int unload_module(void)
134{
136 sub = NULL;
138 router = NULL;
139 return 0;
140}
141
142static int load_module(void)
143{
144 /* You can create a message router to route messages by type */
147 if (!router) {
149 }
151 updates, NULL);
153
154 /* Or a subscription to receive all of the messages from a topic */
156 if (!sub) {
159 }
161}
162
163AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "Example of how to use Stasis",
164 .support_level = AST_MODULE_SUPPORT_EXTENDED,
165 .load = load_module,
166 .unload = unload_module,
167 .requires = "res_statsd"
Asterisk main include file. File version handling, generic pbx functions.
#define ast_free(a)
Definition: astmm.h:180
@ AST_FLAG_DEAD
Definition: channel.h:1065
static void update(int code_size, int y, int wi, int fi, int dq, int sr, int dqsez, struct g726_state *state_ptr)
Definition: codec_g726.c:367
struct stasis_topic * ast_channel_topic_all(void)
A topic which publishes the events for all channels.
struct stasis_message_type * ast_channel_snapshot_type(void)
Message type for ast_channel_snapshot_update.
Asterisk module definitions.
@ AST_MODFLAG_DEFAULT
Definition: module.h:329
#define AST_MODULE_INFO(keystr, flags_to_set, desc, fields...)
Definition: module.h:557
@ AST_MODULE_SUPPORT_EXTENDED
Definition: module.h:122
#define ASTERISK_GPL_KEY
The text the key() function should return.
Definition: module.h:46
@ AST_MODULE_LOAD_SUCCESS
Definition: module.h:70
@ AST_MODULE_LOAD_DECLINE
Module has failed to load, may be in an inconsistent state.
Definition: module.h:78
static struct stasis_subscription * sub
Statsd channel stats. Exmaple of how to subscribe to Stasis events.
static void default_route(void *data, struct stasis_subscription *sub, struct stasis_message *message)
Router callback for any message that doesn't otherwise have a route.
static struct stasis_message_router * router
static void statsmaker(void *data, struct stasis_subscription *sub, struct stasis_message *message)
Subscription callback for all channel messages.
static void updates(void *data, struct stasis_subscription *sub, struct stasis_message *message)
Router callback for ast_channel_snapshot_update messages.
static int load_module(void)
static int unload_module(void)
#define NULL
Definition: resample.c:96
struct stasis_message_type * stasis_message_type(const struct stasis_message *msg)
Get the message type for a stasis_message.
void * stasis_message_data(const struct stasis_message *msg)
Get the data contained in a message.
int stasis_subscription_final_message(struct stasis_subscription *sub, struct stasis_message *msg)
Determine whether a message is the final message to be received on a subscription.
Definition: stasis.c:1175
struct stasis_subscription * stasis_unsubscribe_and_join(struct stasis_subscription *subscription)
Cancel a subscription, blocking until the last message is processed.
Definition: stasis.c:1135
const char * stasis_message_type_name(const struct stasis_message_type *type)
Gets the name of a given message type.
#define stasis_subscribe(topic, callback, data)
Definition: stasis.h:649
const struct timeval * stasis_message_timestamp(const struct stasis_message *msg)
Get the time when a message was created.
#define stasis_message_router_create(topic)
Create a new message router object.
int stasis_message_router_add(struct stasis_message_router *router, struct stasis_message_type *message_type, stasis_subscription_cb callback, void *data)
Add a route to a message router.
void stasis_message_router_unsubscribe_and_join(struct stasis_message_router *router)
Unsubscribe the router from the upstream topic, blocking until the final message has been processed.
int stasis_message_router_set_default(struct stasis_message_router *router, stasis_subscription_cb callback, void *data)
Sets the default route of a router.
#define AST_STATSD_METER
Definition: statsd.h:48
#define AST_STATSD_TIMER
Definition: statsd.h:41
#define AST_STATSD_GAUGE
Support for publishing to a statsd server.
Definition: statsd.h:32
void ast_statsd_log_string(const char *metric_name, const char *metric_type, const char *value, double sample_rate)
Send a stat to the configured statsd server.
Definition: res_statsd.c:117
void ast_statsd_log(const char *metric_name, const char *metric_type, intmax_t value)
Send a stat to the configured statsd server.
Definition: res_statsd.c:232
char * ast_str_buffer(const struct ast_str *buf)
Returns the string buffer within the ast_str buf.
Definition: strings.h:761
#define ast_str_create(init_len)
Create a malloc'ed dynamic length string.
Definition: strings.h:659
int ast_str_set(struct ast_str **buf, ssize_t max_len, const char *fmt,...)
Set a dynamic string using variable arguments.
Definition: strings.h:1113
Structure representing a change of snapshot of channel state.
Support for dynamic strings.
Definition: strings.h:623
Time-related functions and macros.
int64_t ast_tvdiff_ms(struct timeval end, struct timeval start)
Computes the difference (in milliseconds) between two struct timeval instances.
Definition: time.h:107
#define ast_test_flag(p, flag)
Definition: utils.h:63
#define RAII_VAR(vartype, varname, initval, dtor)
Declare a variable that will call a destructor function when it goes out of scope.
Definition: utils.h:941