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-xid';
  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     try {
  31             this.xreq =  new XMLHttpRequest();
  32     } catch(e) {
  33             try {
  34                     this.xreq = new ActiveXObject("Msxml2.XMLHTTP");
  35             } catch (e2) {
  36                         this.xreq = new ActiveXObject("Microsoft.XMLHTTP");
  37             }
  38     }
  39
  40 }
  41
  42 OpenSRF.XHRequest.prototype.send = function() {
  43     var xhr_req = this;
  44     var xreq = this.xreq
  45
  46     if(this.args.timeout) {
  47         /* this is a standard blocking (non-multipart) call */
  48         xreq.open('POST', OSRF_HTTP_TRANSLATOR, false);
  49
  50     } else {
  51
  52         if(!navigator.userAgent.match(/mozilla/i)) {
  53
  54             /* standard asynchronous call */
  55             xreq.onreadystatechange = function() {
  56                 if(xreq.readyState == 4)
  57                     xhr_req.core_handler();
  58             }
  59             xreq.open('POST', OSRF_HTTP_TRANSLATOR, true);
  60
  61         } else {
  62
  63             /* asynchronous multipart call */
  64             xreq.multipart = true;
  65             xreq.onload = function(evt) {xhr_req.core_handler();}
  66             xreq.open('POST', OSRF_HTTP_TRANSLATOR, true);
  67             xreq.setRequestHeader(OSRF_HTTP_HEADER_MULTIPART, 'true');
  68
  69             /* multipart requests do not pass the status info to the onload if there
  70                is no new data to load.  Capture the status on the readystate handler */
  71             xreq.onreadystatechange = function() {
  72                 if(xreq.readyState == 4 && xreq.status >= 400)
  73                     xhr_req.transport_error_handler();
  74             }
  75         }
  76     }
  77
  78     xreq.setRequestHeader('Content-Type', OSRF_POST_CONTENT_TYPE);
  79     xreq.setRequestHeader(OSRF_HTTP_HEADER_THREAD, this.args.thread);
  80     if(this.args.rcpt)
  81         xreq.setRequestHeader(OSRF_HTTP_HEADER_TO, this.args.rcpt);
  82     else
  83         xreq.setRequestHeader(OSRF_HTTP_HEADER_SERVICE, this.args.rcpt_service);
  84
  85     var post = 'osrf-msg=' + encodeURIComponent(js2JSON([this.message.serialize()]));
  86     xreq.send(post);
  87
  88     if(this.args.timeout) /* this was a blocking call, manually run the handler */
  89         this.core_handler()
  90
  91     return this;
  92 }
  93
  94 OpenSRF.XHRequest.prototype.core_handler = function() {
  95     sender = this.xreq.getResponseHeader(OSRF_HTTP_HEADER_FROM);
  96     thread = this.xreq.getResponseHeader(OSRF_HTTP_HEADER_THREAD);
  97     json = this.xreq.responseText;
  98     stat = this.xreq.status;
  99
 100     if(stat >= 400)
 101         return this.transport_error_handler();
 102
 103     OpenSRF.Stack.push(
 104         new OpenSRF.NetMessage(null, sender, thread, json),
 105         {
 106             onresponse : this.args.onresponse,
 107             oncomplete : this.args.oncomplete,
 108             onerror : this.args.onerror,
 109             onmethoderror : this.method_error_handler()
 110         }
 111     );
 112 }
 113
 114
 115 OpenSRF.XHRequest.prototype.method_error_handler = function() {
 116     var xhr = this;
 117     return function(req, status, status_text) {
 118         if(xhr.args.onmethoderror)
 119             xhr.args.onmethoderror(req, status, status_text);
 120         if(xhr.args.onerror)
 121             xhr.args.onerror(xhr.message, xhr.args.rcpt || xhr.args.rcpt_service, xhr.args.thread);
 122     }
 123 }
 124
 125 OpenSRF.XHRequest.prototype.transport_error_handler = function() {
 126     if(this.args.ontransporterror)
 127         this.args.ontransporterror(this.xreq);
 128     if(this.args.onerror)
 129         this.args.onerror(this.message, this.args.rcpt || this.args.rcpt_service, this.args.thread);
 130 }
 131
 132