ari_websockets.c File Reference

WebSocket support for RESTful API's. More...

#include "asterisk.h"
#include "asterisk/ari.h"
#include "asterisk/astobj2.h"
#include "asterisk/http_websocket.h"
#include "asterisk/stasis_app.h"
#include "internal.h"

Include dependency graph for ari_websockets.c:

Go to the source code of this file.

Data Structures
struct	ast_ari_websocket_session

Macros
#define	VALIDATION_FAILED

Functions
void	ari_handle_websocket (struct ast_websocket_server *ws_server, struct ast_tcptls_session_instance *ser, const char *uri, enum ast_http_method method, struct ast_variable *get_params, struct ast_variable *headers)
	Wrapper for invoking the websocket code for an incoming connection. More...
struct ast_ari_websocket_session *	ast_ari_websocket_session_create (struct ast_websocket *ws_session, int(*validator)(struct ast_json *))
	Create an ARI WebSocket session. More...
struct ast_sockaddr *	ast_ari_websocket_session_get_remote_addr (struct ast_ari_websocket_session *session)
	Get the remote address from an ARI WebSocket. More...
const char *	ast_ari_websocket_session_id (const struct ast_ari_websocket_session *session)
	Get the Session ID for an ARI WebSocket. More...
struct ast_json *	ast_ari_websocket_session_read (struct ast_ari_websocket_session *session)
	Read a message from an ARI WebSocket. More...
int	ast_ari_websocket_session_write (struct ast_ari_websocket_session *session, struct ast_json *message)
	Send a message to an ARI WebSocket. More...
static int	null_validator (struct ast_json *json)
	Validator that always succeeds. More...
static void	websocket_session_dtor (void *obj)

Detailed Description

WebSocket support for RESTful API's.

Author

David M. Lee, II dlee@.nosp@m.digi.nosp@m.um.co.nosp@m.m

Definition in file ari_websockets.c.

Macro Definition Documentation

VALIDATION_FAILED

#define VALIDATION_FAILED

Value:

"{"                  \
   "  \"error\": \"InvalidMessage\","     \
   "  \"message\": \"Message validation failed\""  \
   "}"

Definition at line 152 of file ari_websockets.c.

Referenced by ast_ari_websocket_session_write().

Function Documentation

ari_handle_websocket()

void ari_handle_websocket	(	struct ast_websocket_server *	ws_server,
		struct ast_tcptls_session_instance *	ser,
		const char *	uri,
		enum ast_http_method	method,
		struct ast_variable *	get_params,
		struct ast_variable *	headers
	)

Wrapper for invoking the websocket code for an incoming connection.

Parameters

ws_server	WebSocket server to invoke.
ser	HTTP session.
uri	Requested URI.
method	Requested HTTP method.
get_params	Parsed query parameters.
headers	Parsed HTTP headers.

Definition at line 191 of file ari_websockets.c.

References ast_websocket_uri_cb(), and ast_http_uri::data.

Referenced by ast_ari_invoke().

{
   struct ast_http_uri fake_urih = {
      .data = ws_server,
   };
   ast_websocket_uri_cb(ser, &fake_urih, uri, method, get_params,
      headers);
}

ast_ari_websocket_session_create()

struct ast_ari_websocket_session* ast_ari_websocket_session_create	(	struct ast_websocket *	ws_session,
		int(*)(struct ast_json *)	validator
	)

Create an ARI WebSocket session.

If NULL is given for the validator function, no validation will be performed.

Parameters

ws_session	Underlying WebSocket session.
validator	Function to validate outgoing messages.

Returns

New ARI WebSocket session.

NULL on error.

Definition at line 54 of file ari_websockets.c.

References ao2_alloc, ao2_cleanup, ao2_ref, ast_ari_config_get(), ast_log, ast_websocket_set_nonblock(), ast_websocket_set_timeout(), config, errno, LOG_ERROR, LOG_WARNING, NULL, null_validator(), RAII_VAR, session, ast_ari_websocket_session::validator, websocket_session_dtor(), and ast_ari_websocket_session::ws_session.

Referenced by ast_ari_events_event_websocket_ws_established_cb().

{
   RAII_VAR(struct ast_ari_websocket_session *, session, NULL, ao2_cleanup);
   RAII_VAR(struct ast_ari_conf *, config, ast_ari_config_get(), ao2_cleanup);

   if (ws_session == NULL) {
      return NULL;
   }

   if (config == NULL || config->general == NULL) {
      return NULL;
   }

   if (validator == NULL) {
      validator = null_validator;
   }

   if (ast_websocket_set_nonblock(ws_session) != 0) {
      ast_log(LOG_ERROR,
         "ARI web socket failed to set nonblock; closing: %s\n",
         strerror(errno));
      return NULL;
   }

   if (ast_websocket_set_timeout(ws_session, config->general->write_timeout)) {
      ast_log(LOG_WARNING, "Failed to set write timeout %d on ARI web socket\n",
         config->general->write_timeout);
   }

   session = ao2_alloc(sizeof(*session), websocket_session_dtor);
   if (!session) {
      return NULL;
   }

   ao2_ref(ws_session, +1);
   session->ws_session = ws_session;
   session->validator = validator;

   ao2_ref(session, +1);
   return session;
}

ast_ari_websocket_session_get_remote_addr()

struct ast_sockaddr* ast_ari_websocket_session_get_remote_addr

(

struct ast_ari_websocket_session *

session

)

Get the remote address from an ARI WebSocket.

Parameters

session

Session to write to.

Returns

ast_sockaddr (does not have to be freed)

Definition at line 185 of file ari_websockets.c.

References ast_websocket_remote_address(), and ast_ari_websocket_session::ws_session.

Referenced by ast_ari_websocket_session_write(), and stasis_app_message_handler().

{
   return ast_websocket_remote_address(session->ws_session);
}

ast_ari_websocket_session_id()

const char* ast_ari_websocket_session_id

(

const struct ast_ari_websocket_session *

session

)

Get the Session ID for an ARI WebSocket.

Parameters

session

Session to query.

Returns

Session ID.

NULL on error.

Definition at line 203 of file ari_websockets.c.

References ast_websocket_session_id(), and ast_ari_websocket_session::ws_session.

Referenced by ast_ari_websocket_events_event_websocket_established().

{
   return ast_websocket_session_id(session->ws_session);
}

ast_ari_websocket_session_read()

struct ast_json* ast_ari_websocket_session_read

(

struct ast_ari_websocket_session *

session

)

Read a message from an ARI WebSocket.

Parameters

session

Session to read from.

Returns

Message received.

NULL if WebSocket could not be read.

Definition at line 97 of file ari_websockets.c.

References ast_debug, ast_json_load_buf(), ast_json_ref(), ast_json_unref(), ast_log, ast_wait_for_input(), ast_websocket_fd(), AST_WEBSOCKET_OPCODE_CLOSE, AST_WEBSOCKET_OPCODE_TEXT, ast_websocket_read(), errno, LOG_WARNING, NULL, RAII_VAR, and ast_ari_websocket_session::ws_session.

Referenced by ast_ari_websocket_events_event_websocket_established().

{
   RAII_VAR(struct ast_json *, message, NULL, ast_json_unref);

   if (ast_websocket_fd(session->ws_session) < 0) {
      return NULL;
   }

   while (!message) {
      int res;
      char *payload;
      uint64_t payload_len;
      enum ast_websocket_opcode opcode;
      int fragmented;

      res = ast_wait_for_input(
         ast_websocket_fd(session->ws_session), -1);

      if (res <= 0) {
         ast_log(LOG_WARNING, "WebSocket poll error: %s\n",
            strerror(errno));
         return NULL;
      }

      res = ast_websocket_read(session->ws_session, &payload,
         &payload_len, &opcode, &fragmented);

      if (res != 0) {
         ast_log(LOG_WARNING, "WebSocket read error: %s\n",
            strerror(errno));
         return NULL;
      }

      switch (opcode) {
      case AST_WEBSOCKET_OPCODE_CLOSE:
         ast_debug(1, "WebSocket closed\n");
         return NULL;
      case AST_WEBSOCKET_OPCODE_TEXT:
         message = ast_json_load_buf(payload, payload_len, NULL);
         if (message == NULL) {
            ast_log(LOG_WARNING,
               "WebSocket input failed to parse\n");
         }

         break;
      default:
         /* Ignore all other message types */
         break;
      }
   }

   return ast_json_ref(message);
}

ast_ari_websocket_session_write()

int ast_ari_websocket_session_write	(	struct ast_ari_websocket_session *	session,
		struct ast_json *	message
	)

Send a message to an ARI WebSocket.

Parameters

session	Session to write to.
message	Message to send.

Returns

0 on success.

Non-zero on error.

Definition at line 158 of file ari_websockets.c.

References ast_ari_json_format(), ast_ari_websocket_session_get_remote_addr(), ast_json_dump_string_format(), ast_json_free(), ast_log, ast_sockaddr_stringify(), ast_websocket_write_string(), LOG_ERROR, LOG_NOTICE, NULL, RAII_VAR, str, VALIDATION_FAILED, ast_ari_websocket_session::validator, and ast_ari_websocket_session::ws_session.

Referenced by event_session_update_websocket(), and stasis_app_message_handler().

{
   RAII_VAR(char *, str, NULL, ast_json_free);

#ifdef AST_DEVMODE
   if (!session->validator(message)) {
      ast_log(LOG_ERROR, "Outgoing message failed validation\n");
      return ast_websocket_write_string(session->ws_session, VALIDATION_FAILED);
   }
#endif

   str = ast_json_dump_string_format(message, ast_ari_json_format());

   if (str == NULL) {
      ast_log(LOG_ERROR, "Failed to encode JSON object\n");
      return -1;
   }

   if (ast_websocket_write_string(session->ws_session, str)) {
      ast_log(LOG_NOTICE, "Problem occurred during websocket write to %s, websocket closed\n",
         ast_sockaddr_stringify(ast_ari_websocket_session_get_remote_addr(session)));
      return -1;
   }
   return 0;
}

null_validator()

static int null_validator ( struct ast_json *  json )

static

Validator that always succeeds.

Definition at line 49 of file ari_websockets.c.

Referenced by ast_ari_websocket_session_create().

{
   return 1;
}

websocket_session_dtor()

static void websocket_session_dtor ( void *  obj )

static

Definition at line 38 of file ari_websockets.c.

References ast_websocket_unref(), NULL, session, and ast_ari_websocket_session::ws_session.

Referenced by ast_ari_websocket_session_create().

{
   struct ast_ari_websocket_session *session = obj;

   ast_websocket_unref(session->ws_session);
   session->ws_session = NULL;
}