src/javascript/opensrf_xhr.js

   1 /* -----------------------------------------------------------------------
   2  * Copyright (C) 2008  Georgia Public Library Service
   3  * Bill Erickson <erickson@esilibrary.com>
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  * ----------------------------------------------------------------------- */
  15
  16 var OSRF_HTTP_HEADER_TO = 'X-OpenSRF-to';
  17 var OSRF_HTTP_HEADER_XID = 'X-OpenSRF-thread';
  18 var OSRF_HTTP_HEADER_FROM = 'X-OpenSRF-from';
  19 var OSRF_HTTP_HEADER_THREAD = 'X-OpenSRF-thread';
  20 var OSRF_HTTP_HEADER_TIMEOUT = 'X-OpenSRF-timeout';
  21 var OSRF_HTTP_HEADER_SERVICE = 'X-OpenSRF-service';
  22 var OSRF_HTTP_HEADER_MULTIPART = 'X-OpenSRF-multipart';
  23 var OSRF_HTTP_TRANSLATOR = '/osrf-http-translator'; /* XXX config */
  24 var OSRF_POST_CONTENT_TYPE = 'application/x-www-form-urlencoded';
  25
  26
  27 OpenSRF.XHRequest = function(osrf_msg, args) {
  28     this.message = osrf_msg;
  29     this.args = args;
  30     this.xreq = new XMLHttpRequest(); /* XXX browser check */
  31 }
  32
  33 OpenSRF.XHRequest.prototype.send = function() {
  34     var xhr_req = this;
  35     var xreq = this.xreq
  36
  37     if(this.args.timeout) {
  38         /* this is a standard blocking (non-multipart) call */
  39         xreq.open('POST', OSRF_HTTP_TRANSLATOR, false);
  40
  41     } else {
  42
  43         if( /* XXX browser != mozilla */ false ) {
  44
  45             /* standard asynchronous call */
  46             xreq.onreadystatechange = function() {
  47                 if(xreq.readyState == 4)
  48                     xhr_req.core_handler();
  49             }
  50             xreq.open('POST', OSRF_HTTP_TRANSLATOR, true);
  51
  52         } else {
  53
  54             /* asynchronous multipart call */
  55             xreq.multipart = true;
  56             xreq.onload = function(evt) {xhr_req.core_handler();}
  57             xreq.open('POST', OSRF_HTTP_TRANSLATOR, true);
  58             xreq.setRequestHeader(OSRF_HTTP_HEADER_MULTIPART, 'true');
  59         }
  60     }
  61
  62     xreq.setRequestHeader('Content-Type', OSRF_POST_CONTENT_TYPE);
  63     xreq.setRequestHeader(OSRF_HTTP_HEADER_THREAD, this.args.thread);
  64     if(this.args.rcpt)
  65         xreq.setRequestHeader(OSRF_HTTP_HEADER_TO, this.args.rcpt);
  66     else
  67         xreq.setRequestHeader(OSRF_HTTP_HEADER_SERVICE, this.args.rcpt_service);
  68
  69     var post = 'osrf-msg=' + encodeURIComponent(js2JSON([this.message.serialize()]));
  70     xreq.send(post);
  71
  72     if(this.args.timeout) /* this was a blocking call, manually run the handler */
  73         this.core_handler()
  74
  75     return this;
  76 }
  77
  78
  79 OpenSRF.XHRequest.prototype.core_handler = function() {
  80     sender = this.xreq.getResponseHeader(OSRF_HTTP_HEADER_FROM);
  81     thread = this.xreq.getResponseHeader(OSRF_HTTP_HEADER_THREAD);
  82     json = this.xreq.responseText;
  83     stat = this.xreq.status;
  84
  85     var xhr = this;
  86     OpenSRF.Stack.push(
  87         new OpenSRF.NetMessage(null, sender, thread, json),
  88
  89         function(ses, req) {
  90             if(ses) {
  91                 if(ses.state == OSRF_APP_SESSION_CONNECTED &&
  92                     ses.onconnect && !ses.onconnect_called) {
  93                         ses.onconnect_called = true;
  94                         ses.onconnect();
  95                 }
  96             }
  97
  98             if(req) {
  99                 if(req.response_queue.length > 0 && xhr.args.onresponse)
 100                     return xhr.args.onresponse(req);
 101
 102                 if(req.complete && xhr.args.oncomplete && !xhr.args.oncomplete_called) {
 103                     xhr.args.oncomplete_called = true;
 104                     return xhr.args.oncomplete(req);
 105                 }
 106             }
 107         }
 108     );
 109 }
 110