2 @file osrf_app_session.c
3 @brief Implementation of osrfAppSession.
7 #include "opensrf/osrf_app_session.h"
8 #include "opensrf/osrf_stack.h"
10 struct osrf_app_request_struct {
11 /** The controlling session. */
12 struct osrf_app_session_struct* session;
14 /** Request id. It is the same as the thread_trace of the REQUEST message
15 for which it was created.
18 /** True if we have received a 'request complete' message from our request. */
20 /** The original REQUEST message payload. */
22 /** Linked list of responses to the request. */
25 /** Boolean; if true, then a call that is waiting on a response will reset the
26 timeout and set this variable back to false. */
28 /** Linkage pointers for a linked list. We maintain a hash table of pending requests,
29 and each slot of the hash table is a doubly linked list. */
34 static inline unsigned int request_id_hash( int req_id );
35 static osrfAppRequest* find_app_request( const osrfAppSession* session, int req_id );
36 static void add_app_request( osrfAppSession* session, osrfAppRequest* req );
38 /* Send the given message */
39 static int _osrf_app_session_send( osrfAppSession*, osrfMessage* msg );
41 static int osrfAppSessionMakeLocaleRequest(
42 osrfAppSession* session, const jsonObject* params, const char* method_name,
43 int protocol, osrfStringArray* param_strings, char* locale );
45 /** @brief The global session cache.
47 Key: session_id. Data: osrfAppSession.
49 static osrfHash* osrfAppSessionCache = NULL;
51 // --------------------------------------------------------------------------
53 // --------------------------------------------------------------------------
56 @brief Create a new osrfAppRequest.
57 @param session Pointer to the osrfAppSession that will own the new osrfAppRequest.
58 @param msg Pointer to the osrfMessage representing the request.
59 @return Pointer to the new osrfAppRequest.
61 The calling code is responsible for freeing the osrfAppRequest by calling
62 _osrf_app_request_free().
64 static osrfAppRequest* _osrf_app_request_init(
65 osrfAppSession* session, osrfMessage* msg ) {
67 osrfAppRequest* req = safe_malloc(sizeof(osrfAppRequest));
69 req->session = session;
70 req->request_id = msg->thread_trace;
74 req->reset_timeout = 0;
83 @brief Free an osrfAppRequest and everything it owns.
84 @param req Pointer to an osrfAppRequest.
86 static void _osrf_app_request_free( osrfAppRequest * req ) {
89 osrfMessageFree( req->payload );
91 /* Free the messages in the result queue */
92 osrfMessage* next_msg;
93 while( req->result ) {
94 next_msg = req->result->next;
95 osrfMessageFree( req->result );
96 req->result = next_msg;
104 @brief Append a new message to the list of responses to a request.
105 @param req Pointer to the osrfAppRequest for the original REQUEST message.
106 @param result Pointer to an osrfMessage received in response to the request.
108 For each osrfAppRequest we maintain a linked list of response messages, and traverse
111 static void _osrf_app_request_push_queue( osrfAppRequest* req, osrfMessage* result ){
112 if(req == NULL || result == NULL)
115 osrfLogDebug( OSRF_LOG_MARK, "App Session pushing request [%d] onto request queue",
116 result->thread_trace );
117 if(req->result == NULL) {
118 req->result = result; // Add the first node
122 // Find the last node in the list, and append the new node to it
123 osrfMessage* ptr = req->result;
124 osrfMessage* ptr2 = req->result->next;
134 @brief Remove an osrfAppRequest (identified by request_id) from an osrfAppSession.
135 @param session Pointer to the osrfAppSession that owns the osrfAppRequest.
136 @param req_id request_id of the osrfAppRequest to be removed.
138 void osrf_app_session_request_finish( osrfAppSession* session, int req_id ) {
141 // Search the hash table for the request in question
142 unsigned int index = request_id_hash( req_id );
143 osrfAppRequest* old_req = session->request_hash[ index ];
145 if( old_req->request_id == req_id )
148 old_req = old_req->next;
152 // Remove the request from the doubly linked list
154 old_req->prev->next = old_req->next;
156 session->request_hash[ index ] = old_req->next;
159 old_req->next->prev = old_req->prev;
161 _osrf_app_request_free( old_req );
167 @brief Derive a hash key from a request id.
168 @param req_id The request id.
169 @return The corresponding hash key; an index into request_hash[].
171 If OSRF_REQUEST_HASH_SIZE is a power of two, then this calculation should
172 reduce to a binary AND.
174 static inline unsigned int request_id_hash( int req_id ) {
175 return ((unsigned int) req_id ) % OSRF_REQUEST_HASH_SIZE;
179 @brief Search for an osrfAppRequest in the hash table, given a request id.
180 @param session Pointer to the relevant osrfAppSession.
181 @param req_id The request_id of the osrfAppRequest being sought.
182 @return A pointer to the osrfAppRequest if found, or NULL if not.
184 static osrfAppRequest* find_app_request( const osrfAppSession* session, int req_id ) {
186 osrfAppRequest* req = session->request_hash[ request_id_hash( req_id) ];
188 if( req->request_id == req_id )
198 @brief Add an osrfAppRequest to the hash table of a given osrfAppSession.
199 @param session Pointer to the session to which the request belongs.
200 @param req Pointer to the osrfAppRequest to be stored.
202 Find the right spot in the hash table; then add the request to the linked list at that
203 spot. We just add it to the head of the list, without trying to maintain any particular
206 static void add_app_request( osrfAppSession* session, osrfAppRequest* req ) {
207 if( session && req ) {
208 unsigned int index = request_id_hash( req->request_id );
209 req->next = session->request_hash[ index ];
211 session->request_hash[ index ] = req;
216 @brief Request a reset of the timeout period for a request.
217 @param session Pointer to the relevant osrfAppSession.
218 @param req_id Request ID of the request whose timeout is to be reset.
220 This happens when a client receives a STATUS message with a status code
221 OSRF_STATUS_CONTINUE; in effect the server is asking for more time.
223 The request to be reset is identified by the combination of session and request id.
225 void osrf_app_session_request_reset_timeout( osrfAppSession* session, int req_id ) {
228 osrfLogDebug( OSRF_LOG_MARK, "Resetting request timeout %d", req_id );
229 osrfAppRequest* req = find_app_request( session, req_id );
231 req->reset_timeout = 1;
235 @brief Fetch the next response message to a given previous request, subject to a timeout.
236 @param req Pointer to the osrfAppRequest representing the request.
237 @param timeout Maxmimum time to wait, in seconds.
239 @return Pointer to the next osrfMessage for this request, if one is available, or if it
240 becomes available before the end of the timeout; otherwise NULL;
242 If there is already a message available in the input queue for this request, dequeue and
243 return it immediately. Otherwise wait up to timeout seconds until you either get an
244 input message for the specified request, run out of time, or encounter an error.
246 If the only message we receive for this request is a STATUS message with a status code
247 OSRF_STATUS_COMPLETE, then return NULL. That means that the server has nothing further
248 to send in response to this request.
250 You may also receive other messages for other requests, and other sessions. These other
251 messages will be wholly or partially processed behind the scenes while you wait for the
254 static osrfMessage* _osrf_app_request_recv( osrfAppRequest* req, int timeout ) {
256 if(req == NULL) return NULL;
258 if( req->result != NULL ) {
259 /* Dequeue the next message in the list */
260 osrfMessage* tmp_msg = req->result;
261 req->result = req->result->next;
265 time_t start = time(NULL);
266 time_t remaining = (time_t) timeout;
268 // Wait repeatedly for input messages until you either receive one for the request
269 // you're interested in, run out of time, or encounter an error.
270 // Wait repeatedly because you may also receive messages for other requests, or for
271 // other sessions, and process them behind the scenes. These are not the messages
272 // you're looking for.
273 while( remaining >= 0 ) {
274 /* tell the session to wait for stuff */
275 osrfLogDebug( OSRF_LOG_MARK, "In app_request receive with remaining time [%d]",
279 osrf_app_session_queue_wait( req->session, 0, NULL );
280 if(req->session->transport_error) {
281 osrfLogError(OSRF_LOG_MARK, "Transport error in recv()");
285 if( req->result != NULL ) { /* if we received any results for this request */
286 /* dequeue the first message in the list */
287 osrfLogDebug( OSRF_LOG_MARK, "app_request_recv received a message, returning it" );
288 osrfMessage* ret_msg = req->result;
289 req->result = ret_msg->next;
290 if (ret_msg->sender_locale)
291 osrf_app_session_set_locale(req->session, ret_msg->sender_locale);
299 osrf_app_session_queue_wait( req->session, (int) remaining, NULL );
301 if(req->session->transport_error) {
302 osrfLogError(OSRF_LOG_MARK, "Transport error in recv()");
306 if( req->result != NULL ) { /* if we received any results for this request */
307 /* dequeue the first message in the list */
308 osrfLogDebug( OSRF_LOG_MARK, "app_request_recv received a message, returning it");
309 osrfMessage* ret_msg = req->result;
310 req->result = ret_msg->next;
311 if (ret_msg->sender_locale)
312 osrf_app_session_set_locale(req->session, ret_msg->sender_locale);
320 // Determine how much time is left
321 if(req->reset_timeout) {
322 // We got a reprieve. This happens when a client receives a STATUS message
323 // with a status code OSRF_STATUS_CONTINUE. We restart the timer from the
324 // beginning -- but only once. We reset reset_timeout to zero. so that a
325 // second attempted reprieve will allow, at most, only one more second.
326 remaining = (time_t) timeout;
327 req->reset_timeout = 0;
328 osrfLogDebug( OSRF_LOG_MARK, "Received a timeout reset");
330 remaining -= (int) (time(NULL) - start);
334 // Timeout exhausted; no messages for the request in question
335 char* paramString = jsonObjectToJSON(req->payload->_params);
336 osrfLogInfo( OSRF_LOG_MARK, "Returning NULL from app_request_recv after timeout: %s %s",
337 req->payload->method_name, paramString);
343 // --------------------------------------------------------------------------
345 // --------------------------------------------------------------------------
348 @brief Install a copy of a locale string in a specified session.
349 @param session Pointer to the osrfAppSession in which the locale is to be installed.
350 @param locale The locale string to be copied and installed.
351 @return A pointer to the installed copy of the locale string.
353 char* osrf_app_session_set_locale( osrfAppSession* session, const char* locale ) {
354 if (!session || !locale)
357 if(session->session_locale) {
358 if( strlen(session->session_locale) >= strlen(locale) ) {
359 /* There's room available; just copy */
360 strcpy(session->session_locale, locale);
362 free(session->session_locale);
363 session->session_locale = strdup( locale );
366 session->session_locale = strdup( locale );
369 return session->session_locale;
373 @brief Find the osrfAppSession for a given session id.
374 @param session_id The session id to look for.
375 @return Pointer to the corresponding osrfAppSession if found, or NULL if not.
377 Search the global session cache for the specified session id.
379 osrfAppSession* osrf_app_session_find_session( const char* session_id ) {
381 return osrfHashGet( osrfAppSessionCache, session_id );
387 @brief Add a session to the global session cache, keyed by session id.
388 @param session Pointer to the osrfAppSession to be added.
390 If a cache doesn't exist yet, create one. It's an osrfHash using session ids for the
391 key and osrfAppSessions for the data.
393 static void _osrf_app_session_push_session( osrfAppSession* session ) {
395 if( osrfAppSessionCache == NULL )
396 osrfAppSessionCache = osrfNewHash();
397 if( osrfHashGet( osrfAppSessionCache, session->session_id ) )
398 return; // A session with this id is already in the cache. Shouldn't happen.
399 osrfHashSet( osrfAppSessionCache, session, session->session_id );
404 @brief Create an osrfAppSession for a client.
405 @param remote_service Name of the service to which to connect
406 @return Pointer to the new osrfAppSession if successful, or NULL upon error.
408 Allocate memory for an osrfAppSession, and initialize it as follows:
410 - For talking with Jabber, grab an existing transport_client. It must have been
411 already set up by a prior call to osrfSystemBootstrapClientResc().
412 - Build a Jabber ID for addressing the service.
413 - Build a session ID based on a fine-grained timestamp and a process ID. This ID is
414 intended to be unique across the system, but uniqueness is not strictly guaranteed.
415 - Initialize various other bits and scraps.
416 - Add the session to the global session cache.
418 Do @em not connect to the service at this point.
420 osrfAppSession* osrfAppSessionClientInit( const char* remote_service ) {
422 if (!remote_service) {
423 osrfLogWarning( OSRF_LOG_MARK, "No remote service specified in osrfAppSessionClientInit");
427 osrfAppSession* session = safe_malloc(sizeof(osrfAppSession));
429 // Grab an existing transport_client for talking with Jabber
430 session->transport_handle = osrfSystemGetTransportClient();
431 if( session->transport_handle == NULL ) {
432 osrfLogWarning( OSRF_LOG_MARK, "No transport client for service 'client'");
437 // Get a list of domain names from the config settings;
438 // ignore all but the first one in the list.
439 osrfStringArray* arr = osrfNewStringArray(8);
440 osrfConfigGetValueList(NULL, arr, "/domain");
441 const char* domain = osrfStringArrayGetString(arr, 0);
443 osrfLogWarning( OSRF_LOG_MARK, "No domains specified in the OpenSRF config file");
445 osrfStringArrayFree(arr);
449 // Get a router name from the config settings.
450 char* router_name = osrfConfigGetValue(NULL, "/router_name");
452 osrfLogWarning( OSRF_LOG_MARK, "No router name specified in the OpenSRF config file");
454 osrfStringArrayFree(arr);
458 char target_buf[512];
459 target_buf[ 0 ] = '\0';
461 // Using the router name, domain, and service name,
462 // build a Jabber ID for addressing the service.
463 int len = snprintf( target_buf, sizeof(target_buf), "%s@%s/%s",
464 router_name ? router_name : "(null)",
465 domain ? domain : "(null)",
466 remote_service ? remote_service : "(null)" );
467 osrfStringArrayFree(arr);
470 if( len >= sizeof( target_buf ) ) {
471 osrfLogWarning( OSRF_LOG_MARK, "Buffer overflow for remote_id");
476 session->remote_id = strdup(target_buf);
477 session->orig_remote_id = strdup(session->remote_id);
478 session->remote_service = strdup(remote_service);
479 session->session_locale = NULL;
480 session->transport_error = 0;
483 #ifdef ASSUME_STATELESS
484 session->stateless = 1;
485 osrfLogDebug( OSRF_LOG_MARK, "%s session is stateless", remote_service );
487 session->stateless = 0;
488 osrfLogDebug( OSRF_LOG_MARK, "%s session is NOT stateless", remote_service );
491 /* build a chunky, random session id */
494 snprintf(id, sizeof(id), "%f.%d%ld", get_timestamp_millis(), (int)time(NULL), (long) getpid());
495 session->session_id = strdup(id);
496 osrfLogDebug( OSRF_LOG_MARK, "Building a new client session with id [%s] [%s]",
497 session->remote_service, session->session_id );
499 session->thread_trace = 0;
500 session->state = OSRF_SESSION_DISCONNECTED;
501 session->type = OSRF_SESSION_CLIENT;
503 session->userData = NULL;
504 session->userDataFree = NULL;
506 // Initialize the hash table
508 for( i = 0; i < OSRF_REQUEST_HASH_SIZE; ++i )
509 session->request_hash[ i ] = NULL;
511 _osrf_app_session_push_session( session );
516 @brief Create an osrfAppSession for a server.
517 @param session_id The session ID. In practice this comes from the thread member of
518 the transport message from the client.
519 @param our_app The name of the service being provided.
520 @param remote_id Jabber ID of the client.
521 @return Pointer to the newly created osrfAppSession if successful, or NULL upon failure.
523 If there is already a session with the specified id, report an error. Otherwise:
525 - Allocate memory for an osrfAppSession.
526 - For talking with Jabber, grab an existing transport_client. It should have been
527 already set up by a prior call to osrfSystemBootstrapClientResc().
528 - Install a copy of the @a our_app string as remote_service.
529 - Install copies of the @a remote_id string as remote_id and orig_remote_id.
530 - Initialize various other bits and scraps.
531 - Add the session to the global session cache.
533 Do @em not respond to the client at this point.
535 osrfAppSession* osrf_app_server_session_init(
536 const char* session_id, const char* our_app, const char* remote_id ) {
538 osrfLogDebug( OSRF_LOG_MARK, "Initing server session with session id %s, service %s,"
539 " and remote_id %s", session_id, our_app, remote_id );
541 osrfAppSession* session = osrf_app_session_find_session( session_id );
543 osrfLogWarning( OSRF_LOG_MARK, "App session already exists for session id %s",
548 session = safe_malloc(sizeof(osrfAppSession));
550 // Grab an existing transport_client for talking with Jabber
551 session->transport_handle = osrfSystemGetTransportClient();
552 if( session->transport_handle == NULL ) {
553 osrfLogWarning( OSRF_LOG_MARK, "No transport client for service '%s'", our_app );
558 // Decide from a config setting whether the session is stateless or not. However
559 // this determination is pointless because it will immediately be overruled according
560 // to the compile-time macro ASSUME_STATELESS.
562 char* statel = osrf_settings_host_value("/apps/%s/stateless", our_app );
563 if(statel) stateless = atoi(statel);
566 session->remote_id = strdup(remote_id);
567 session->orig_remote_id = strdup(remote_id);
568 session->session_id = strdup(session_id);
569 session->remote_service = strdup(our_app);
570 session->stateless = stateless;
572 #ifdef ASSUME_STATELESS
573 session->stateless = 1;
575 session->stateless = 0;
578 session->thread_trace = 0;
579 session->state = OSRF_SESSION_DISCONNECTED;
580 session->type = OSRF_SESSION_SERVER;
581 session->session_locale = NULL;
583 session->userData = NULL;
584 session->userDataFree = NULL;
586 // Initialize the hash table
588 for( i = 0; i < OSRF_REQUEST_HASH_SIZE; ++i )
589 session->request_hash[ i ] = NULL;
591 _osrf_app_session_push_session( session );
596 @brief Create a REQUEST message, send it, and save it for future reference.
597 @param session Pointer to the current session, which has the addressing information.
598 @param params One way of specifying the parameters for the method.
599 @param method_name The name of the method to be called.
600 @param protocol Protocol.
601 @param param_strings Another way of specifying the parameters for the method.
602 @return The request ID of the resulting REQUEST message, or -1 upon error.
604 DEPRECATED. Use osrfAppSessionSendRequest() instead. It is identical except that it
605 doesn't use the param_strings argument, which is redundant, confusing, and unused.
607 If @a params is non-NULL, use it to specify the parameters to the method. Otherwise
608 use @a param_strings.
610 If @a params points to a JSON_ARRAY, then pass each element of the array as a separate
611 parameter. If @a params points to any other kind of jsonObject, pass it as a single
614 If @a params is NULL, and @a param_strings is not NULL, then each pointer in the
615 osrfStringArray must point to a JSON string encoding a parameter. Pass them.
617 At this writing, all calls to this function use @a params to pass parameters, rather than
620 This function is a thin wrapper for osrfAppSessionMakeLocaleRequest().
622 int osrfAppSessionMakeRequest(
623 osrfAppSession* session, const jsonObject* params,
624 const char* method_name, int protocol, osrfStringArray* param_strings ) {
626 osrfLogWarning( OSRF_LOG_MARK, "Function osrfAppSessionMakeRequest() is deprecasted; "
627 "call osrfAppSessionSendRequest() instead" );
628 return osrfAppSessionMakeLocaleRequest( session, params,
629 method_name, protocol, param_strings, NULL );
633 @brief Create a REQUEST message, send it, and save it for future reference.
634 @param session Pointer to the current session, which has the addressing information.
635 @param params One way of specifying the parameters for the method.
636 @param method_name The name of the method to be called.
637 @param protocol Protocol.
638 @return The request ID of the resulting REQUEST message, or -1 upon error.
640 If @a params points to a JSON_ARRAY, then pass each element of the array as a separate
641 parameter. If @a params points to any other kind of jsonObject, pass it as a single
644 This function is a thin wrapper for osrfAppSessionMakeLocaleRequest().
646 int osrfAppSessionSendRequest( osrfAppSession* session, const jsonObject* params,
647 const char* method_name, int protocol ) {
649 return osrfAppSessionMakeLocaleRequest( session, params,
650 method_name, protocol, NULL, NULL );
654 @brief Create a REQUEST message, send it, and save it for future reference.
655 @param session Pointer to the current session, which has the addressing information.
656 @param params One way of specifying the parameters for the method.
657 @param method_name The name of the method to be called.
658 @param protocol Protocol.
659 @param param_strings Another way of specifying the parameters for the method.
660 @param locale Pointer to a locale string.
661 @return The request ID of the resulting REQUEST message, or -1 upon error.
663 See the discussion of osrfAppSessionSendRequest(), which at this writing is the only
664 place that calls this function, except for the similar but deprecated function
665 osrfAppSessionMakeRequest().
667 At this writing, the @a param_strings and @a locale parameters are always NULL.
669 static int osrfAppSessionMakeLocaleRequest(
670 osrfAppSession* session, const jsonObject* params, const char* method_name,
671 int protocol, osrfStringArray* param_strings, char* locale ) {
673 if(session == NULL) return -1;
677 osrfMessage* req_msg = osrf_message_init( REQUEST, ++(session->thread_trace), protocol );
678 osrf_message_set_method(req_msg, method_name);
681 osrf_message_set_locale(req_msg, locale);
682 } else if (session->session_locale) {
683 osrf_message_set_locale(req_msg, session->session_locale);
687 osrf_message_set_params(req_msg, params);
693 for(i = 0; i!= param_strings->size ; i++ ) {
694 osrf_message_add_param(req_msg,
695 osrfStringArrayGetString(param_strings,i));
700 osrfAppRequest* req = _osrf_app_request_init( session, req_msg );
701 if(_osrf_app_session_send( session, req_msg ) ) {
702 osrfLogWarning( OSRF_LOG_MARK, "Error sending request message [%d]",
703 session->thread_trace );
704 _osrf_app_request_free(req);
708 osrfLogDebug( OSRF_LOG_MARK, "Pushing [%d] onto request queue for session [%s] [%s]",
709 req->request_id, session->remote_service, session->session_id );
710 add_app_request( session, req );
711 return req->request_id;
715 @brief Mark an osrfAppRequest (identified by session and ID) as complete.
716 @param session Pointer to the osrfAppSession that owns the request.
717 @param request_id Request ID of the osrfAppRequest.
719 void osrf_app_session_set_complete( osrfAppSession* session, int request_id ) {
723 osrfAppRequest* req = find_app_request( session, request_id );
729 @brief Determine whether a osrfAppRequest, identified by session and ID, is complete.
730 @param session Pointer to the osrfAppSession that owns the request.
731 @param request_id Request ID of the osrfAppRequest.
732 @return Non-zero if the request is complete; zero if it isn't, or if it can't be found.
734 int osrf_app_session_request_complete( const osrfAppSession* session, int request_id ) {
738 osrfAppRequest* req = find_app_request( session, request_id );
740 return req->complete;
746 @brief Reset the remote ID of a session to its original remote ID.
747 @param session Pointer to the osrfAppSession to be reset.
749 void osrf_app_session_reset_remote( osrfAppSession* session ){
753 osrfLogDebug( OSRF_LOG_MARK, "App Session [%s] [%s] resetting remote id to %s",
754 session->remote_service, session->session_id, session->orig_remote_id );
756 osrf_app_session_set_remote( session, session->orig_remote_id );
760 @brief Set a session's remote ID to a specified value.
761 @param session Pointer to the osrfAppSession whose remote ID is to be set.
762 @param remote_id Pointer to the new remote id.
764 void osrf_app_session_set_remote( osrfAppSession* session, const char* remote_id ) {
765 if( session == NULL || remote_id == NULL )
768 if( session->remote_id ) {
769 if( strlen(session->remote_id) >= strlen(remote_id) ) {
770 // There's enough room; just copy it
771 strcpy(session->remote_id, remote_id);
773 free(session->remote_id );
774 session->remote_id = strdup( remote_id );
777 session->remote_id = strdup( remote_id );
781 @brief Append an osrfMessage to the list of responses to an osrfAppRequest.
782 @param session Pointer to the osrfAppSession that owns the request.
783 @param msg Pointer to the osrfMessage to be added.
785 The thread_trace member of the osrfMessage is the request_id of the osrfAppRequest.
786 Find the corresponding request in the session and append the osrfMessage to its list.
788 void osrf_app_session_push_queue( osrfAppSession* session, osrfMessage* msg ) {
789 if( session && msg ) {
790 osrfAppRequest* req = find_app_request( session, msg->thread_trace );
792 _osrf_app_request_push_queue( req, msg );
797 @brief Connect to the remote service.
798 @param session Pointer to the osrfAppSession for the service.
799 @return 1 if successful, or 0 if not.
801 If already connected, exit immediately, reporting success. Otherwise, build a CONNECT
802 message and send it to the service. Wait for up to five seconds for an acknowledgement.
804 The timeout value is currently hard-coded. Perhaps it should be configurable.
806 int osrfAppSessionConnect( osrfAppSession* session ) {
811 if(session->state == OSRF_SESSION_CONNECTED) {
815 int timeout = 5; /* XXX CONFIG VALUE */
817 osrfLogDebug( OSRF_LOG_MARK, "AppSession connecting to %s", session->remote_id );
819 /* defaulting to protocol 1 for now */
820 osrfMessage* con_msg = osrf_message_init( CONNECT, session->thread_trace, 1 );
822 // Address this message to the router
823 osrf_app_session_reset_remote( session );
824 session->state = OSRF_SESSION_CONNECTING;
825 int ret = _osrf_app_session_send( session, con_msg );
826 osrfMessageFree(con_msg);
830 time_t start = time(NULL);
831 time_t remaining = (time_t) timeout;
833 // Wait for the acknowledgement. We look for it repeatedly because, under the covers,
834 // we may receive and process messages other than the one we're looking for.
835 while( session->state != OSRF_SESSION_CONNECTED && remaining >= 0 ) {
836 osrf_app_session_queue_wait( session, remaining, NULL );
837 if(session->transport_error) {
838 osrfLogError(OSRF_LOG_MARK, "cannot communicate with %s", session->remote_service);
841 remaining -= (int) (time(NULL) - start);
844 if(session->state == OSRF_SESSION_CONNECTED)
845 osrfLogDebug( OSRF_LOG_MARK, " * Connected Successfully to %s", session->remote_service );
847 if(session->state != OSRF_SESSION_CONNECTED)
854 @brief Disconnect from the remote service. No response is expected.
855 @param session Pointer to the osrfAppSession to be disconnected.
856 @return 1 in all cases.
858 If we're already disconnected, return immediately without doing anything. Likewise if
859 we have a stateless session and we're in the process of connecting. Otherwise, send a
860 DISCONNECT message to the service.
862 int osrf_app_session_disconnect( osrfAppSession* session){
866 if(session->state == OSRF_SESSION_DISCONNECTED)
869 if(session->stateless && session->state != OSRF_SESSION_CONNECTED) {
870 osrfLogDebug( OSRF_LOG_MARK,
871 "Exiting disconnect on stateless session %s",
872 session->session_id);
876 osrfLogDebug(OSRF_LOG_MARK, "AppSession disconnecting from %s", session->remote_id );
878 osrfMessage* dis_msg = osrf_message_init( DISCONNECT, session->thread_trace, 1 );
879 _osrf_app_session_send( session, dis_msg );
880 session->state = OSRF_SESSION_DISCONNECTED;
882 osrfMessageFree( dis_msg );
883 osrf_app_session_reset_remote( session );
888 @brief Resend a request message, as specified by session and request id.
889 @param session Pointer to the osrfAppSession.
890 @param req_id Request ID for the request to be resent.
891 @return Zero if successful, or if the specified request cannot be found; 1 if the
892 request is already complete, or if the attempt to resend the message fails.
894 The choice of return codes may seem seem capricious, but at this writing nothing
895 pays any attention to the return code anyway.
897 int osrf_app_session_request_resend( osrfAppSession* session, int req_id ) {
898 osrfAppRequest* req = find_app_request( session, req_id );
903 } else if(!req->complete) {
904 osrfLogDebug( OSRF_LOG_MARK, "Resending request [%d]", req->request_id );
905 rc = _osrf_app_session_send( req->session, req->payload );
914 @brief Send one or more osrfMessages to the remote service or client.
915 @param session Pointer to the osrfAppSession responsible for sending the message(s).
916 @param msgs Pointer to an array of pointers to osrfMessages.
917 @param size How many messages to send.
918 @return 0 upon success, or -1 upon failure.
920 static int osrfAppSessionSendBatch( osrfAppSession* session, osrfMessage* msgs[], int size ) {
922 if( !(session && msgs && size > 0) ) return -1;
925 osrfMessage* msg = msgs[0];
929 // First grab and process any input messages, for any app session. This gives us
930 // a chance to see any CONNECT or DISCONNECT messages that may have arrived. We
931 // may also see some unrelated messages, but we have to process those sooner or
932 // later anyway, so we might as well do it now.
933 osrf_app_session_queue_wait( session, 0, NULL );
935 if(session->state != OSRF_SESSION_CONNECTED) {
937 if(session->stateless) { /* stateless session always send to the root listener */
938 osrf_app_session_reset_remote(session);
942 /* do an auto-connect if necessary */
943 if( ! session->stateless &&
944 (msg->m_type != CONNECT) &&
945 (msg->m_type != DISCONNECT) &&
946 (session->state != OSRF_SESSION_CONNECTED) ) {
948 if(!osrfAppSessionConnect( session ))
955 // Bundle all the osrfMessages into a single transport_message, then send it.
956 char* string = osrfMessageSerializeBatch(msgs, size);
960 transport_message* t_msg = message_init(
961 string, "", session->session_id, session->remote_id, NULL );
962 message_set_osrf_xid( t_msg, osrfLogGetXid() );
964 retval = client_send_message( session->transport_handle, t_msg );
966 osrfLogError(OSRF_LOG_MARK, "client_send_message failed");
968 osrfLogInfo(OSRF_LOG_MARK, "[%s] sent %d bytes of data to %s",
969 session->remote_service, strlen(string), t_msg->recipient );
971 osrfLogDebug(OSRF_LOG_MARK, "Sent: %s", string );
974 message_free( t_msg );
981 @brief Send a single osrfMessage to the remote service or client.
982 @param session Pointer to the osrfAppSession.
983 @param msg Pointer to the osrfMessage to be sent.
984 @return zero upon success, or 1 upon failure.
986 A thin wrapper. Create an array of one element, and pass it to osrfAppSessionSendBatch().
988 static int _osrf_app_session_send( osrfAppSession* session, osrfMessage* msg ){
989 if( !(session && msg) )
993 return - osrfAppSessionSendBatch( session, a, 1 );
998 @brief Wait for any input messages to arrive, and process them as needed.
999 @param session Pointer to the osrfAppSession whose transport_session we will use.
1000 @param timeout How many seconds to wait for the first input message.
1001 @param recvd Pointer to an boolean int. If you receive at least one message, set the boolean
1002 to true; otherwise set it to false.
1003 @return 0 upon success (even if a timeout occurs), or -1 upon failure.
1005 A thin wrapper for osrf_stack_process(). The timeout applies only to the first
1006 message; process subsequent messages if they are available, but don't wait for them.
1008 The first parameter identifies an osrfApp session, but all we really use it for is to
1009 get a pointer to the transport_session. Typically, a given process opens only a single
1010 transport_session (to talk to the Jabber server), and all app sessions in that process
1011 use the same transport_session.
1013 Hence this function indiscriminately waits for input messages for all osrfAppSessions
1014 tied to the same Jabber session, not just the one specified.
1016 Dispatch each message to the appropriate processing routine, depending on its type
1017 and contents, and on whether we're acting as a client or as a server for that message.
1018 For example, a response to a request may be appended to the input queue of the
1019 relevant request. A server session receiving a REQUEST message may execute the
1020 requested method. And so forth.
1022 int osrf_app_session_queue_wait( osrfAppSession* session, int timeout, int* recvd ){
1023 if(session == NULL) return 0;
1024 osrfLogDebug(OSRF_LOG_MARK, "AppSession in queue_wait with timeout %d", timeout );
1025 return osrf_stack_process(session->transport_handle, timeout, recvd);
1029 @brief Shut down and destroy an osrfAppSession.
1030 @param session Pointer to the osrfAppSession to be destroyed.
1032 If this is a client session, send a DISCONNECT message.
1034 Remove the session from the global session cache.
1036 Free all associated resources, including any pending osrfAppRequests.
1038 void osrfAppSessionFree( osrfAppSession* session ){
1039 if(session == NULL) return;
1043 osrfLogDebug(OSRF_LOG_MARK, "AppSession [%s] [%s] destroying self and deleting requests",
1044 session->remote_service, session->session_id );
1045 /* disconnect if we're a client */
1046 if(session->type == OSRF_SESSION_CLIENT
1047 && session->state != OSRF_SESSION_DISCONNECTED ) {
1048 osrfMessage* dis_msg = osrf_message_init( DISCONNECT, session->thread_trace, 1 );
1049 _osrf_app_session_send( session, dis_msg );
1050 osrfMessageFree(dis_msg);
1053 /* Remove self from the global session cache */
1055 osrfHashRemove( osrfAppSessionCache, session->session_id );
1057 /* Free the memory */
1059 if( session->userDataFree && session->userData )
1060 session->userDataFree(session->userData);
1062 if(session->session_locale)
1063 free(session->session_locale);
1065 free(session->remote_id);
1066 free(session->orig_remote_id);
1067 free(session->session_id);
1068 free(session->remote_service);
1070 // Free the request hash
1072 for( i = 0; i < OSRF_REQUEST_HASH_SIZE; ++i ) {
1073 osrfAppRequest* app = session->request_hash[ i ];
1075 osrfAppRequest* next = app->next;
1076 _osrf_app_request_free( app );
1084 @brief Wait for a response to a given request, subject to a timeout.
1085 @param session Pointer to the osrfAppSession that owns the request.
1086 @param req_id Request ID for the request.
1087 @param timeout How many seconds to wait.
1088 @return A pointer to the received osrfMessage if one arrives; otherwise NULL.
1090 A thin wrapper. Given a session and a request ID, look up the corresponding request
1091 and pass it to _osrf_app_request_recv().
1093 osrfMessage* osrfAppSessionRequestRecv(
1094 osrfAppSession* session, int req_id, int timeout ) {
1095 if(req_id < 0 || session == NULL)
1097 osrfAppRequest* req = find_app_request( session, req_id );
1098 return _osrf_app_request_recv( req, timeout );
1102 @brief In response to a specified request, send a payload of data to a client.
1103 @param ses Pointer to the osrfAppSession that owns the request.
1104 @param requestId Request ID of the osrfAppRequest.
1105 @param data Pointer to a jsonObject containing the data payload.
1106 @return 0 upon success, or -1 upon failure.
1108 Translate the jsonObject to a JSON string, and send it wrapped in a RESULT message.
1110 The only failure detected is if either of the two pointer parameters is NULL.
1112 int osrfAppRequestRespond( osrfAppSession* ses, int requestId, const jsonObject* data ) {
1113 if( !ses || ! data )
1116 osrfMessage* msg = osrf_message_init( RESULT, requestId, 1 );
1117 osrf_message_set_status_info( msg, NULL, "OK", OSRF_STATUS_OK );
1118 char* json = jsonObjectToJSON( data );
1120 osrf_message_set_result_content( msg, json );
1121 _osrf_app_session_send( ses, msg );
1124 osrfMessageFree( msg );
1131 @brief Send one or two messages to a client in response to a specified request.
1132 @param ses Pointer to the osrfAppSession that owns the request.
1133 @param requestId Request ID of the osrfAppRequest.
1134 @param data Pointer to a jsonObject containing the data payload.
1135 @return Zero in all cases.
1137 If the @a data parameter is not NULL, translate the jsonObject into a JSON string, and
1138 incorporate that string into a RESULT message as as the payload . Also build a STATUS
1139 message indicating that the response is complete. Send both messages bundled together
1140 in the same transport_message.
1142 If the @a data parameter is NULL, send only a STATUS message indicating that the response
1145 int osrfAppRequestRespondComplete(
1146 osrfAppSession* ses, int requestId, const jsonObject* data ) {
1148 osrfMessage* status = osrf_message_init( STATUS, requestId, 1);
1149 osrf_message_set_status_info( status, "osrfConnectStatus", "Request Complete",
1150 OSRF_STATUS_COMPLETE );
1153 osrfMessage* payload = osrf_message_init( RESULT, requestId, 1 );
1154 osrf_message_set_status_info( payload, NULL, "OK", OSRF_STATUS_OK );
1156 char* json = jsonObjectToJSON( data );
1157 osrf_message_set_result_content( payload, json );
1164 osrfAppSessionSendBatch( ses, ms, 2 );
1166 osrfMessageFree( payload );
1168 osrfAppSessionSendBatch( ses, &status, 1 );
1171 osrfMessageFree( status );
1177 @brief Send a STATUS message, for a specified request, back to the client.
1178 @param ses Pointer to the osrfAppSession connected to the client.
1179 @param type A numeric code denoting the status.
1180 @param name A string naming the status.
1181 @param reqId The request ID of the request.
1182 @param message A brief message describing the status.
1183 @return 0 upon success, or -1 upon failure.
1185 The only detected failure is when the @a ses parameter is NULL.
1187 int osrfAppSessionStatus( osrfAppSession* ses, int type,
1188 const char* name, int reqId, const char* message ) {
1191 osrfMessage* msg = osrf_message_init( STATUS, reqId, 1);
1192 osrf_message_set_status_info( msg, name, message, type );
1193 _osrf_app_session_send( ses, msg );
1194 osrfMessageFree( msg );
1201 @brief Free the global session cache.
1203 Note that the osrfHash that implements the global session cache does @em not have a
1204 callback function installed for freeing its cargo. As a result, any remaining
1205 osrfAppSessions are leaked, along with all the osrfAppRequests and osrfMessages they
1208 void osrfAppSessionCleanup( void ) {
1209 osrfHashFree(osrfAppSessionCache);
1210 osrfAppSessionCache = NULL;
1214 @brief Arrange for immediate termination of the process.
1215 @param ses Pointer to the current osrfAppSession.
1217 Typical use case: a server drone loses its database connection, thereby becoming useless.
1218 It terminates so that it will not receive further requests, being unable to service them.
1220 void osrfAppSessionPanic( osrfAppSession* ses ) {