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/osrf_message.h"
34 #include "opensrf/osrf_app_session.h"
35 #include "opensrf/string_array.h"
37 #include "objson/object.h"
38 #include "objson/json_parser.h"
44 * This function is registered as a handler for HTTP methods and will
45 * therefore be invoked for all GET requests (and others). Regardless
46 * of the request type, this function simply sends a message to
47 * STDERR (which httpd redirects to logs/error_log). A real module
48 * would do *alot* more at this point.
50 #define MODULE_NAME "ils_rest_gateway_module"
52 #define MODULE_NAME "ils_gateway_module"
56 struct session_list_struct {
57 osrf_app_session* session;
58 struct session_list_struct* next;
61 typedef struct session_list_struct session_list;
63 static session_list* the_list = NULL;
65 static void del_session( char* service ) {
66 if(!service || ! the_list)
69 debug_handler("In del_sesion for %s", service );
70 session_list* prev = the_list;
71 session_list* item = prev->next;
73 if(!strcmp(prev->session->remote_service, service)) {
74 info_handler("Removing gateway session for %s", service );
76 osrf_app_session_destroy(prev->session);
82 if( !strcmp(item->session->remote_service, service)) {
83 info_handler("Removing gateway session for %s", service );
84 prev->next = item->next;
85 osrf_app_session_destroy(item->session);
93 warning_handler("Attempt to remove gateway session "
94 "that does not exist: %s", service );
98 // if(update) we add 1 to the serve_count
99 static osrf_app_session* find_session( char* service, int update ) {
101 session_list* item = the_list;
104 if(!strcmp(item->session->remote_service,service)) {
106 if( item->serve_count++ > 20 ) {
107 debug_handler("Disconnected session on 20 requests => %s", service);
108 osrf_app_session_disconnect(item->session);
109 del_session(service);
111 //item->serve_count = 0;
114 debug_handler("Found session for %s in gateway cache", service);
115 return item->session;
123 static void add_session( char* service, osrf_app_session* session ) {
127 if(find_session(service,0))
130 debug_handler("Add session for %s to the cache", service );
132 session_list* new_item = (session_list*) safe_malloc(sizeof(session_list));
133 new_item->session = session;
134 //new_item->service = service;
135 new_item->serve_count = 0;
138 session_list* second = the_list->next;
140 new_item->next = second;
147 static void mod_ils_gateway_child_init(apr_pool_t *p, server_rec *s) {
148 if( ! osrf_system_bootstrap_client( "/openils/conf/gateway.xml") ) {
149 fatal_handler("Unable to load gateway config file...");
152 /* we don't want to waste time parsing json that we're not going to look at*/
153 osrf_message_set_json_parse_result(0);
154 osrf_message_set_json_parse_params(0);
155 fprintf(stderr, "Bootstrapping %d\n", getpid() );
159 static int mod_ils_gateway_method_handler (request_rec *r) {
162 /* make sure we're needed first thing*/
163 if (strcmp(r->handler, MODULE_NAME ))
167 apr_pool_t *p = r->pool; /* memory pool */
168 char* arg = r->args; /* url query string */
170 char* service = NULL; /* service to connect to */
171 char* method = NULL; /* method to perform */
173 //json* exception = NULL; /* returned in error conditions */
174 object* exception = NULL; /* returned in error conditions */
175 string_array* sarray = init_string_array(12); /* method parameters */
177 growing_buffer* buffer = NULL; /* POST data */
178 growing_buffer* tmp_buf = NULL; /* temp buffer */
180 char* key = NULL; /* query item name */
181 char* val = NULL; /* query item value */
185 /* verify we are connected */
186 if(!osrf_system_get_transport_client()) {
187 fatal_handler("Bootstrap Failed, no transport client");
188 return HTTP_INTERNAL_SERVER_ERROR;
193 /* gather the post args and append them to the url query string */
194 if( !strcmp(r->method,"POST") ) {
196 ap_setup_client_block(r,REQUEST_CHUNKED_DECHUNK);
198 if(! ap_should_client_block(r)) {
199 warning_handler("No Post Body");
204 buffer = buffer_init(1025);
206 while(ap_get_client_block(r, body, 1024)) {
207 debug_handler("Apache read POST block data: %s\n", body);
208 buffer_add( buffer, body );
213 tmp_buf = buffer_init(1024);
214 buffer_add(tmp_buf,arg);
215 buffer_add(tmp_buf,buffer->buf);
216 arg = (char*) apr_pstrdup(p, tmp_buf->buf);
217 buffer_free(tmp_buf);
219 arg = (char*) apr_pstrdup(p, buffer->buf);
225 debug_handler("params args are %s", arg);
228 if( ! arg || !arg[0] ) { /* we received no request */
229 warning_handler("No Args");
233 r->allowed |= (AP_METHOD_BIT << M_GET);
234 r->allowed |= (AP_METHOD_BIT << M_POST);
237 //char* argcopy = (char*) apr_pstrdup(p, arg);
239 //while( argcopy && (val = ap_getword(p, (const char**) &argcopy, '&'))) {
240 while( arg && (val = ap_getword(p, (const char**) &arg, '&'))) {
242 //const char* val2 = val;
244 key = ap_getword(r->pool, (const char**) &val, '=');
248 ap_unescape_url((char*)key);
249 ap_unescape_url((char*)val);
251 if(!strcmp(key,"service"))
254 if(!strcmp(key,"method"))
257 if(!strcmp(key,"param"))
258 string_array_add(sarray, val);
262 info_handler("Performing(%d): service %s | method %s | \n",
263 getpid(), service, method );
266 for( k = 0; k!= sarray->size; k++ ) {
267 info_handler( "param %s", string_array_get_string(sarray,k));
271 osrf_app_session* session = find_session(service,1);
274 debug_handler("building new session for %s", service );
275 session = osrf_app_client_session_init(service);
276 add_session(service, session);
280 osrf_app_session* session = osrf_app_client_session_init(service);
282 debug_handler("MOD session service: %s", session->remote_service );
285 /* connect to the remote service */
287 if(!osrf_app_session_connect(session)) {
288 exception = json_object_new_object();
289 json_object_object_add( exception, "is_err", json_object_new_int(1));
290 json_object_object_add( exception,
291 "err_msg", json_object_new_string("Unable to connect to remote service"));
293 ap_rputs(json_object_to_json_string(exception), r );
294 json_object_put(exception);
299 int req_id = osrf_app_session_make_req( session, NULL, method, 1, sarray );
300 string_array_destroy(sarray);
302 osrf_message* omsg = NULL;
304 growing_buffer* result_data = buffer_init(256);
305 buffer_add(result_data, "[");
307 /* gather result data */
308 while((omsg = osrf_app_session_request_recv( session, req_id, 60 ))) {
310 if( omsg->result_string ) {
311 buffer_add(result_data, omsg->result_string);
312 buffer_add( result_data, ",");
317 /* build the exception information */
318 growing_buffer* exc_buffer = buffer_init(256);
319 buffer_add( exc_buffer, "\nReceived Exception:\nName: " );
320 buffer_add( exc_buffer, omsg->status_name );
321 buffer_add( exc_buffer, "\nStatus: " );
322 buffer_add( exc_buffer, omsg->status_text );
323 buffer_add( exc_buffer, "\nStatus: " );
327 sprintf( code, "%d", omsg->status_code );
328 buffer_add( exc_buffer, code );
330 /* build the exception object */
332 exception = json_object_new_object();
333 json_object_object_add( exception, "is_err", json_object_new_int(1));
334 json_object_object_add( exception,
335 "err_msg", json_object_new_string(exc_buffer->buf));
338 exception = json_parse_string("{}");
339 exception->add_key(exception, "is_err", json_parse_string("1"));
340 exception->add_key(exception, "err_msg", new_object(exc_buffer->buf) );
342 warning_handler("*** Looks like we got a "
343 "server exception\n%s", exc_buffer->buf );
345 buffer_free(exc_buffer);
346 osrf_message_free(omsg);
350 osrf_message_free(omsg);
354 /* remove trailing comma */
355 if( result_data->buf[strlen(result_data->buf)-1] == ',') {
356 result_data->buf[strlen(result_data->buf)-1] = '\0';
357 result_data->n_used--;
360 buffer_add(result_data,"]");
362 char* content = NULL;
364 /* round up our data */
366 //content = strdup(json_object_to_json_string(exception));
367 //json_object_put(exception);
368 content = strdup(exception->to_json(exception));
369 free_object(exception);
372 /* set content type to text/xml for passing around XML objects */
373 ap_set_content_type(r, "text/xml");
375 content = json_string_to_xml( buffer_data(result_data) );
377 /* set content type to text/plain for passing around JSON objects */
378 ap_set_content_type(r, "text/plain");
380 content = buffer_data(result_data);
385 buffer_free(result_data);
388 debug_handler( "APACHE writing data to web client: %s", content );
393 osrf_app_session_request_finish( session, req_id );
394 debug_handler("gateway process message successfully");
397 osrf_app_session_destroy(session);
403 * This function is a callback and it declares what other functions
404 * should be called for request processing and configuration requests.
405 * This callback function declares the Handlers for other events. */
406 static void mod_ils_gateway_register_hooks (apr_pool_t *p) {
407 // I think this is the call to make to register a handler for method calls (GET PUT et. al.).
408 // We will ask to be last so that the comment has a higher tendency to
410 ap_hook_handler(mod_ils_gateway_method_handler, NULL, NULL, APR_HOOK_MIDDLE);
411 ap_hook_child_init(mod_ils_gateway_child_init,NULL,NULL,APR_HOOK_MIDDLE);
415 * Declare and populate the module's data structure. The
416 * name of this structure ('tut1_module') is important - it
417 * must match the name of the module. This structure is the
418 * only "glue" between the httpd core and the module.
423 module AP_MODULE_DECLARE_DATA ils_rest_gateway_module =
425 STANDARD20_MODULE_STUFF,
431 mod_ils_gateway_register_hooks,
436 module AP_MODULE_DECLARE_DATA ils_gateway_module =
438 STANDARD20_MODULE_STUFF,
444 mod_ils_gateway_register_hooks,