asterisk/res/res_ari_events.c
Ashley Sanders fe804b09b3 ARI: Channels added to Stasis application during WebSocket creation ...
Prior to ASTERISK-24988, the WebSocket handshake was resolved before Stasis
applications were registered. This was done such that the WebSocket would be
ready when an application is registered. However, by creating the WebSocket
first, the client had the ability to make requests for the Stasis application
it thought had been created with the initial handshake request. The inevitable
conclusion of this scenario was the cart being put before the horse.

ASTERISK-24988 resolved half of the problem by ensuring that the applications
were created and registered with Stasis prior to completing the handshake
with the client. While this meant that Stasis was ready when the client
received the green-light from Asterisk, it also meant that the WebSocket was
not yet ready for Stasis to dispatch messages.

This patch introduces a message queuing mechanism for delaying messages from
Stasis applications while the WebSocket is being constructed. When the ARI
event processor receives the message from the WebSocket that it is being
created, the event processor instantiates an event session which contains a
message queue. It then tries to create and register the requested applications
with Stasis. Messages that are dispatched from Stasis between this point and
the point at which the event processor is notified the WebSocket is ready, are
stashed in the queue. Once the WebSocket has been built, the queue's messages
are dispatched in the order in which they were originally received and the
queue is concurrently cleared.

ASTERISK-25181 #close
Reported By: Matt Jordan

Change-Id: Iafef7b85a2e0bf78c114db4c87ffc3d16d671a17
2015-07-31 11:28:10 -05:00

475 lines
12 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2012 - 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.
*/
/*
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* !!!!! DO NOT EDIT !!!!!
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* This file is generated by a mustache template. Please see the original
* template in rest-api-templates/res_ari_resource.c.mustache
*/
/*! \file
*
* \brief WebSocket resource
*
* \author David M. Lee, II <dlee@digium.com>
*/
/*** MODULEINFO
<depend type="module">res_ari</depend>
<depend type="module">res_ari_model</depend>
<depend type="module">res_stasis</depend>
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_REGISTER_FILE()
#include "asterisk/app.h"
#include "asterisk/module.h"
#include "asterisk/stasis_app.h"
#include "ari/resource_events.h"
#if defined(AST_DEVMODE)
#include "ari/ari_model_validators.h"
#endif
#include "asterisk/http_websocket.h"
#define MAX_VALS 128
static int ast_ari_events_event_websocket_ws_attempted_cb(struct ast_tcptls_session_instance *ser,
struct ast_variable *get_params, struct ast_variable *headers, const char *session_id)
{
struct ast_ari_events_event_websocket_args args = {};
int res = 0;
RAII_VAR(struct ast_ari_response *, response, NULL, ast_free);
struct ast_variable *i;
response = ast_calloc(1, sizeof(*response));
if (!response) {
ast_log(LOG_ERROR, "Failed to create response.\n");
goto fin;
}
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "app") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.app_parse = ast_strdup(i->value);
if (!args.app_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.app_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.app_count = 1;
vals[0] = args.app_parse;
} else {
args.app_count = ast_app_separate_args(
args.app_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.app_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.app_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for app");
goto fin;
}
args.app = ast_malloc(sizeof(*args.app) * args.app_count);
if (!args.app) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.app_count; ++j) {
args.app[j] = (vals[j]);
}
} else
{}
}
res = ast_ari_websocket_events_event_websocket_attempted(ser, headers, &args, session_id);
fin: __attribute__((unused))
if (!response) {
ast_http_error(ser, 500, "Server Error", "Memory allocation error");
res = -1;
} else if (response->response_code != 0) {
/* Param parsing failure */
RAII_VAR(char *, msg, NULL, ast_json_free);
if (response->message) {
msg = ast_json_dump_string(response->message);
} else {
ast_log(LOG_ERROR, "Missing response message\n");
}
if (msg) {
ast_http_error(ser, response->response_code, response->response_text, msg);
}
res = -1;
}
ast_free(args.app_parse);
ast_free(args.app);
return res;
}
static void ast_ari_events_event_websocket_ws_established_cb(struct ast_websocket *ws_session,
struct ast_variable *get_params, struct ast_variable *headers)
{
struct ast_ari_events_event_websocket_args args = {};
RAII_VAR(struct ast_ari_response *, response, NULL, ast_free);
struct ast_variable *i;
RAII_VAR(struct ast_websocket *, s, ws_session, ast_websocket_unref);
RAII_VAR(struct ast_ari_websocket_session *, session, NULL, ao2_cleanup);
response = ast_calloc(1, sizeof(*response));
if (!response) {
ast_log(LOG_ERROR, "Failed to create response.\n");
goto fin;
}
#if defined(AST_DEVMODE)
session = ast_ari_websocket_session_create(ws_session,
ast_ari_validate_message_fn());
#else
session = ast_ari_websocket_session_create(ws_session, NULL);
#endif
if (!session) {
ast_log(LOG_ERROR, "Failed to create ARI session\n");
goto fin;
}
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "app") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.app_parse = ast_strdup(i->value);
if (!args.app_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.app_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.app_count = 1;
vals[0] = args.app_parse;
} else {
args.app_count = ast_app_separate_args(
args.app_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.app_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.app_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for app");
goto fin;
}
args.app = ast_malloc(sizeof(*args.app) * args.app_count);
if (!args.app) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.app_count; ++j) {
args.app[j] = (vals[j]);
}
} else
{}
}
ast_ari_websocket_events_event_websocket_established(session, headers, &args);
fin: __attribute__((unused))
if (response && response->response_code != 0) {
/* Param parsing failure */
RAII_VAR(char *, msg, NULL, ast_json_free);
if (response->message) {
msg = ast_json_dump_string(response->message);
} else {
ast_log(LOG_ERROR, "Missing response message\n");
}
if (msg) {
ast_websocket_write(ws_session,
AST_WEBSOCKET_OPCODE_TEXT, msg, strlen(msg));
}
}
ast_free(args.app_parse);
ast_free(args.app);
}
int ast_ari_events_user_event_parse_body(
struct ast_json *body,
struct ast_ari_events_user_event_args *args)
{
struct ast_json *field;
/* Parse query parameters out of it */
field = ast_json_object_get(body, "application");
if (field) {
args->application = ast_json_string_get(field);
}
field = ast_json_object_get(body, "source");
if (field) {
/* If they were silly enough to both pass in a query param and a
* JSON body, free up the query value.
*/
ast_free(args->source);
if (ast_json_typeof(field) == AST_JSON_ARRAY) {
/* Multiple param passed as array */
size_t i;
args->source_count = ast_json_array_size(field);
args->source = ast_malloc(sizeof(*args->source) * args->source_count);
if (!args->source) {
return -1;
}
for (i = 0; i < args->source_count; ++i) {
args->source[i] = ast_json_string_get(ast_json_array_get(field, i));
}
} else {
/* Multiple param passed as single value */
args->source_count = 1;
args->source = ast_malloc(sizeof(*args->source) * args->source_count);
if (!args->source) {
return -1;
}
args->source[0] = ast_json_string_get(field);
}
}
return 0;
}
/*!
* \brief Parameter parsing callback for /events/user/{eventName}.
* \param get_params GET parameters in the HTTP request.
* \param path_vars Path variables extracted from the request.
* \param headers HTTP headers.
* \param[out] response Response to the HTTP request.
*/
static void ast_ari_events_user_event_cb(
struct ast_tcptls_session_instance *ser,
struct ast_variable *get_params, struct ast_variable *path_vars,
struct ast_variable *headers, struct ast_ari_response *response)
{
struct ast_ari_events_user_event_args args = {};
struct ast_variable *i;
RAII_VAR(struct ast_json *, body, NULL, ast_json_unref);
#if defined(AST_DEVMODE)
int is_valid;
int code;
#endif /* AST_DEVMODE */
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "application") == 0) {
args.application = (i->value);
} else
if (strcmp(i->name, "source") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.source_parse = ast_strdup(i->value);
if (!args.source_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.source_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.source_count = 1;
vals[0] = args.source_parse;
} else {
args.source_count = ast_app_separate_args(
args.source_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.source_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.source_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for source");
goto fin;
}
args.source = ast_malloc(sizeof(*args.source) * args.source_count);
if (!args.source) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.source_count; ++j) {
args.source[j] = (vals[j]);
}
} else
{}
}
for (i = path_vars; i; i = i->next) {
if (strcmp(i->name, "eventName") == 0) {
args.event_name = (i->value);
} else
{}
}
/* Look for a JSON request entity */
body = ast_http_get_json(ser, headers);
if (!body) {
switch (errno) {
case EFBIG:
ast_ari_response_error(response, 413, "Request Entity Too Large", "Request body too large");
goto fin;
case ENOMEM:
ast_ari_response_error(response, 500, "Internal Server Error", "Error processing request");
goto fin;
case EIO:
ast_ari_response_error(response, 400, "Bad Request", "Error parsing request body");
goto fin;
}
}
args.variables = body;
ast_ari_events_user_event(headers, &args, response);
#if defined(AST_DEVMODE)
code = response->response_code;
switch (code) {
case 0: /* Implementation is still a stub, or the code wasn't set */
is_valid = response->message == NULL;
break;
case 500: /* Internal Server Error */
case 501: /* Not Implemented */
case 404: /* Application does not exist. */
case 422: /* Event source not found. */
case 400: /* Invalid even tsource URI or userevent data. */
is_valid = 1;
break;
default:
if (200 <= code && code <= 299) {
is_valid = ast_ari_validate_void(
response->message);
} else {
ast_log(LOG_ERROR, "Invalid error response %d for /events/user/{eventName}\n", code);
is_valid = 0;
}
}
if (!is_valid) {
ast_log(LOG_ERROR, "Response validation failed for /events/user/{eventName}\n");
ast_ari_response_error(response, 500,
"Internal Server Error", "Response validation failed");
}
#endif /* AST_DEVMODE */
fin: __attribute__((unused))
ast_free(args.source_parse);
ast_free(args.source);
return;
}
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events_user_eventName = {
.path_segment = "eventName",
.is_wildcard = 1,
.callbacks = {
[AST_HTTP_POST] = ast_ari_events_user_event_cb,
},
.num_children = 0,
.children = { }
};
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events_user = {
.path_segment = "user",
.callbacks = {
},
.num_children = 1,
.children = { &events_user_eventName, }
};
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events = {
.path_segment = "events",
.callbacks = {
},
.num_children = 1,
.children = { &events_user, }
};
static int load_module(void)
{
int res = 0;
struct ast_websocket_protocol *protocol;
if (ast_ari_websocket_events_event_websocket_init() == -1) {
return AST_MODULE_LOAD_FAILURE;
}
events.ws_server = ast_websocket_server_create();
if (!events.ws_server) {
return AST_MODULE_LOAD_FAILURE;
}
protocol = ast_websocket_sub_protocol_alloc("ari");
if (!protocol) {
ao2_ref(events.ws_server, -1);
events.ws_server = NULL;
return AST_MODULE_LOAD_FAILURE;
}
protocol->session_attempted = ast_ari_events_event_websocket_ws_attempted_cb;
protocol->session_established = ast_ari_events_event_websocket_ws_established_cb;
res |= ast_websocket_server_add_protocol2(events.ws_server, protocol);
stasis_app_ref();
res |= ast_ari_add_handler(&events);
return res;
}
static int unload_module(void)
{
ast_ari_remove_handler(&events);
ao2_cleanup(events.ws_server);
events.ws_server = NULL;
stasis_app_unref();
return 0;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "RESTful API module - WebSocket resource",
.support_level = AST_MODULE_SUPPORT_CORE,
.load = load_module,
.unload = unload_module,
.nonoptreq = "res_ari,res_stasis",
);