2 Copyright 2002 Kevin O'Donnell
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * Include the core server components.
23 #include "http_config.h"
24 #include "http_core.h"
25 #include "http_protocol.h"
26 #include "apr_compat.h"
27 #include "apr_strings.h"
32 #include "opensrf/transport_client.h"
33 #include "opensrf/generic_utils.h"
34 #include "opensrf/osrf_message.h"
35 #include "opensrf/osrf_app_session.h"
36 #include "opensrf/string_array.h"
40 * This function is registered as a handler for HTTP methods and will
41 * therefore be invoked for all GET requests (and others). Regardless
42 * of the request type, this function simply sends a message to
43 * STDERR (which httpd redirects to logs/error_log). A real module
44 * would do *alot* more at this point.
46 #define MODULE_NAME "ils_gateway_module"
48 struct session_list_struct {
50 osrf_app_session* session;
51 struct session_list_struct* next;
54 typedef struct session_list_struct session_list;
56 /* the global session cache */
57 static session_list* the_list = NULL;
59 static void del_session( char* service ) {
60 if(!service || ! the_list)
63 debug_handler("In del_sesion for %s", service );
64 session_list* prev = the_list;
65 session_list* item = prev->next;
67 if(!strcmp(prev->session->remote_service, service)) {
68 info_handler("Removing gateway session for %s", service );
70 osrf_app_session_destroy(prev->session);
76 if( !strcmp(item->session->remote_service, service)) {
77 info_handler("Removing gateway session for %s", service );
78 prev->next = item->next;
79 osrf_app_session_destroy(item->session);
87 warning_handler("Attempt to remove gateway session "
88 "that does not exist: %s", service );
92 /* find a session in the list */
93 /* if(update) we add 1 to the serve_count */
94 static osrf_app_session* find_session( char* service, int update ) {
96 session_list* item = the_list;
99 if(!strcmp(item->session->remote_service,service)) {
101 if( item->serve_count++ > 20 ) {
102 debug_handler("Disconnected session on 20 requests => %s", service);
103 osrf_app_session_disconnect(item->session);
104 del_session(service);
106 //item->serve_count = 0;
109 debug_handler("Found session for %s in gateway cache", service);
110 return item->session;
118 /* add a session to the list */
119 static void add_session( char* service, osrf_app_session* session ) {
123 if(find_session(service,0))
126 debug_handler("Add session for %s to the cache", service );
128 session_list* new_item = (session_list*) safe_malloc(sizeof(session_list));
129 new_item->session = session;
130 //new_item->service = service;
131 new_item->serve_count = 0;
134 session_list* second = the_list->next;
136 new_item->next = second;
142 static void mod_ils_gateway_child_init(apr_pool_t *p, server_rec *s) {
143 if( ! osrf_system_bootstrap_client(
144 "/pines/cvs/ILS/OpenSRF/src/gateway/gateway.xml") ) { /* config option */
147 /* we don't want to waste time parsing json that we're not going to look at*/
148 osrf_message_set_json_parse_result(0);
149 osrf_message_set_json_parse_params(0);
150 fprintf(stderr, "Bootstrapping %d\n", getpid() );
154 static int mod_ils_gateway_method_handler (request_rec *r) {
157 /* make sure we're needed first thing*/
158 if (strcmp(r->handler, MODULE_NAME ))
162 apr_pool_t *p = r->pool; /* memory pool */
163 char* arg = r->args; /* url query string */
165 char* service = NULL; /* service to connect to */
166 char* method = NULL; /* method to perform */
168 json* exception = NULL; /* returned in error conditions */
169 string_array* sarray = init_string_array(12); /* method parameters */
171 growing_buffer* buffer = NULL; /* POST data */
172 growing_buffer* tmp_buf = NULL; /* temp buffer */
174 char* key = NULL; /* query item name */
175 char* val = NULL; /* query item value */
179 /* verify we are connected */
180 if(!osrf_system_get_transport_client()) {
181 fatal_handler("Bootstrap Failed, no transport client");
182 return HTTP_INTERNAL_SERVER_ERROR;
185 /* set content type to text/plain for passing around JSON objects */
186 ap_set_content_type(r, "text/plain");
190 /* gather the post args and append them to the url query string */
191 if( !strcmp(r->method,"POST") ) {
193 ap_setup_client_block(r,REQUEST_CHUNKED_DECHUNK);
195 if(! ap_should_client_block(r)) {
196 warning_handler("No Post Body");
201 buffer = buffer_init(1024);
203 while(ap_get_client_block(r, body, 1024)) {
204 buffer_add( buffer, body );
209 tmp_buf = buffer_init(1024);
210 buffer_add(tmp_buf,arg);
211 buffer_add(tmp_buf,buffer->buf);
212 arg = (char*) apr_pstrdup(p, tmp_buf->buf);
213 // arg = buffer_data(tmp_buf);;
214 buffer_free(tmp_buf);
216 arg = (char*) apr_pstrdup(p, buffer->buf);
217 // arg = buffer_data(buffer);
223 debug_handler("params args are %s", arg);
226 if( ! arg || !arg[0] ) { /* we received no request */
227 warning_handler("No Args");
231 r->allowed |= (AP_METHOD_BIT << M_GET);
232 r->allowed |= (AP_METHOD_BIT << M_POST);
235 char* argcopy = (char*) apr_pstrdup(p, arg);
237 while( argcopy && (val = ap_getword(p, (const char**) &argcopy, '&'))) {
239 //const char* val2 = val;
241 key = ap_getword(r->pool, (const char**) &val, '=');
245 ap_unescape_url((char*)key);
246 ap_unescape_url((char*)val);
248 if(!strcmp(key,"service"))
251 if(!strcmp(key,"method"))
254 if(!strcmp(key,"__param"))
255 string_array_add(sarray, val);
259 info_handler("Performing(%d): service %s | method %s | \n",
260 getpid(), service, method );
263 for( k = 0; k!= sarray->size; k++ ) {
264 info_handler( "param %s", string_array_get_string(sarray,k));
267 osrf_app_session* session = find_session(service,1);
270 debug_handler("building new session for %s", service );
271 session = osrf_app_client_session_init(service);
272 add_session(service, session);
275 debug_handler("MOD session service: %s", session->remote_service );
278 /* connect to the remote service */
279 if(!osrf_app_session_connect(session)) {
280 exception = json_object_new_object();
281 json_object_object_add( exception, "is_err", json_object_new_int(1));
282 json_object_object_add( exception,
283 "err_msg", json_object_new_string("Unable to connect to remote service"));
285 ap_rputs(json_object_to_json_string(exception), r );
286 json_object_put(exception);
290 int req_id = osrf_app_session_make_request( session, NULL, method, 1, sarray );
291 string_array_destroy(sarray);
293 osrf_message* omsg = NULL;
295 growing_buffer* result_data = buffer_init(256);
296 buffer_add(result_data, "[");
298 /* gather result data */
299 while((omsg = osrf_app_session_request_recv( session, req_id, 30 ))) {
301 if( omsg->result_string ) {
302 buffer_add(result_data, omsg->result_string);
303 buffer_add( result_data, ",");
308 /* build the exception information */
309 growing_buffer* exc_buffer = buffer_init(256);
310 buffer_add( exc_buffer, "\nReceived Exception:\nName: " );
311 buffer_add( exc_buffer, omsg->status_name );
312 buffer_add( exc_buffer, "\nStatus: " );
313 buffer_add( exc_buffer, omsg->status_text );
314 buffer_add( exc_buffer, "\nStatus: " );
317 sprintf( code, "%d", omsg->status_code );
318 buffer_add( exc_buffer, code );
320 /* build the exception object */
321 exception = json_object_new_object();
322 json_object_object_add( exception, "is_err", json_object_new_int(1));
323 json_object_object_add( exception,
324 "err_msg", json_object_new_string(exc_buffer->buf));
326 warning_handler("*** Looks like we got a "
327 "server exception\n%s", exc_buffer->buf );
329 buffer_free(exc_buffer);
330 osrf_message_free(omsg);
334 osrf_message_free(omsg);
338 /* remove trailing comma */
339 if( result_data->buf[strlen(result_data->buf)-1] == ',') {
340 result_data->buf[strlen(result_data->buf)-1] = '\0';
341 result_data->n_used--;
344 buffer_add(result_data,"]");
346 char* content = NULL;
348 /* round up our data */
350 content = strdup(json_object_to_json_string(exception));
351 json_object_put(exception);
353 content = buffer_data(result_data);
356 buffer_free(result_data);
363 osrf_app_session_request_finish( session, req_id );
364 debug_handler("gateway process message successfully");
371 * This function is a callback and it declares what other functions
372 * should be called for request processing and configuration requests.
373 * This callback function declares the Handlers for other events. */
374 static void mod_ils_gateway_register_hooks (apr_pool_t *p) {
375 // I think this is the call to make to register a handler for method calls (GET PUT et. al.).
376 // We will ask to be last so that the comment has a higher tendency to
378 ap_hook_handler(mod_ils_gateway_method_handler, NULL, NULL, APR_HOOK_MIDDLE);
379 ap_hook_child_init(mod_ils_gateway_child_init,NULL,NULL,APR_HOOK_MIDDLE);
383 * Declare and populate the module's data structure. The
384 * name of this structure ('tut1_module') is important - it
385 * must match the name of the module. This structure is the
386 * only "glue" between the httpd core and the module.
389 module AP_MODULE_DECLARE_DATA ils_gateway_module =
391 STANDARD20_MODULE_STUFF,
397 mod_ils_gateway_register_hooks,