ajax.js

   1 /*
   2
   3 Ajax Debugger.
   4 Provides an in-depth tool to analyze Ajax interactions with web servers.
   5 Copyright (C) 2007  Steven Ray Schronk
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License along
  18 with this program; if not, write to the Free Software Foundation, Inc.,
  19 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20
  21 */
  22
  23
  24 // THREADSAFE ASYNCHRONOUS XMLHTTPRequest
  25 // url = url to send to server
  26 // pageElement = page element to replace when data arrives
  27 // waitMessage =  info to display while waiting for return from server
  28 //                if waitMessage not sent, content will not "blink"
  29 // callBack = javascript function name to run after data has been returned from server
  30 function getPage( url, pageElement, waitMessage, callBack ) {
  31                 var timer = new Date();
  32                 var t_start = timer.getTime();
  33                 //debugEvent(url, "get");
  34
  35   // DON'T DISTURB CONTENT UNLESS NESSISARY
  36   if ( waitMessage != "" ) {  document.getElementById(pageElement).innerHTML = waitMessage; }
  37
  38 // WE USE A JAVASCRIPT FEATURE HERE CALLED "INNER FUNCTIONS"
  39 // USING THESE MEANS THE LOCAL VARIABLES RETAIN THEIR VALUES AFTER THE OUTER FUNCTION
  40 // HAS RETURNED. THIS IS USEFUL FOR THREAD SAFETY, SO
  41 // REASSIGNING THE ONREADYSTATECHANGE FUNCTION DOESN'T STOMP OVER EARLIER REQUESTS.
  42         function ajaxBindCallback(){
  43                 if(ajaxRequest.readyState == 0) { window.status = "Waiting...";      }
  44                 if(ajaxRequest.readyState == 1) { window.status = "Loading Page..."; }
  45                 if(ajaxRequest.readyState == 2) { window.status = "Data Received...";}
  46                 if(ajaxRequest.readyState == 3) { window.status = "Interactive...";  }
  47                 if(ajaxRequest.readyState == 4) {
  48                         window.status = "Transaction Complete...";
  49
  50       // STOP TIMER AND FIND DIFFERENCE
  51       // MUST CREATE NEW TIMER INSTANCE :)
  52       var timer2 = new Date();
  53       var t_end = timer2.getTime();
  54       var t_diff = t_end - t_start;
  55
  56       // TEST HTTP STATUS CODE - DISPLAY IN DUBUGGER AND STATUS
  57       switch (ajaxRequest.status.toString()) {
  58         case "200" :
  59           window.status = "Page Loaded Sucessfully";
  60           document.getElementById(pageElement).innerHTML = ajaxRequest.responseText;
  61           debugEvent(url, "got", ajaxRequest.responseText, t_diff);
  62           break;
  63         case "403" :
  64           window.status = "Forbidden...";
  65           debugEvent(url, "error_403", ajaxRequest.responseText, t_diff);
  66           break;
  67         case "404" :
  68           window.status = "File Not Found...";
  69           debugEvent(url, "error_404", ajaxRequest.responseText, t_diff);
  70           break;
  71         case "500" :
  72           window.status = "File Not Found...";
  73           debugEvent(url, "error_500", ajaxRequest.responseText, t_diff);
  74           break;
  75         default :
  76           window.status = "Unknown Ajax Error..."+ajaxRequest.status.toString();
  77         }
  78                         }
  79         }
  80         var ajaxRequest = null;
  81         // BIND OUR CALLBACK THEN HIT THE SERVER...
  82         if (window.XMLHttpRequest) {
  83                 ajaxRequest = new XMLHttpRequest();
  84                 ajaxRequest.onreadystatechange = ajaxBindCallback;
  85                 ajaxRequest.open("GET", url, true);
  86                 ajaxRequest.send(null);
  87         } else if (window.ActiveXObject) {
  88                 ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
  89                 if (ajaxRequest) {
  90                         ajaxRequest.onreadystatechange = ajaxBindCallback;
  91                         ajaxRequest.open("GET", url, true);
  92                         ajaxRequest.send();
  93                         }
  94                 }
  95         if (callBack != null ) { eval(callBack+'()'); }
  96 }
  97
  98 function sendData(url){
  99                 // START TIMER
 100                 var timer = new Date();
 101                 var t_start = timer.getTime();
 102 // WE USE A JAVASCRIPT FEATURE HERE CALLED "INNER FUNCTIONS"
 103 // USING THESE MEANS THE LOCAL VARIABLES RETAIN THEIR VALUES AFTER THE OUTER FUNCTION
 104 // HAS RETURNED. THIS IS USEFUL FOR THREAD SAFETY, SO
 105 // REASSIGNING THE ONREADYSTATECHANGE FUNCTION DOESN'T STOMP OVER EARLIER REQUESTS.
 106         function ajaxBindCallback(){
 107                 if(ajaxRequest.readyState == 0) { window.status = "Waiting...";      }
 108                 if(ajaxRequest.readyState == 1) { window.status = "Loading Page..."; }
 109                 if(ajaxRequest.readyState == 2) { window.status = "Data Received...";}
 110                 if(ajaxRequest.readyState == 3) { window.status = "Interactive...";  }
 111                 if(ajaxRequest.readyState == 4) {
 112                         window.status = "Transaction Complete...";
 113
 114       // STOP TIMER AND FIND DIFFERENCE
 115       // MUST CREATE NEW TIMER INSTANCE :)
 116       var timer2 = new Date();
 117       var t_end = timer2.getTime();
 118       var t_diff = t_end - t_start;
 119
 120       // TEST HTTP STATUS CODE - DISPLAY IN DUBUGGER AND STATUS
 121       switch (ajaxRequest.status.toString()) {
 122         case "200" :
 123           debugEvent(url, "got", ajaxRequest.responseText, t_diff);
 124           break;
 125         case "403" :
 126           debugEvent(url, "error_403", ajaxRequest.responseText, t_diff);
 127           break;
 128         case "404" :
 129           debugEvent(url, "error_404", ajaxRequest.responseText, t_diff);
 130           break;
 131         case "500" :
 132           debugEvent(url, "error_500", ajaxRequest.responseText, t_diff);
 133           break;
 134         }
 135                         }
 136         }
 137         var ajaxRequest = null;
 138         // BIND OUR CALLBACK THEN HIT THE SERVER...
 139         if (window.XMLHttpRequest) {
 140                 ajaxRequest = new XMLHttpRequest();
 141                 ajaxRequest.onreadystatechange = ajaxBindCallback;
 142                 ajaxRequest.open("GET", url, true);
 143                 ajaxRequest.send(null);
 144         } else if (window.ActiveXObject) {
 145                 ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
 146                 if (ajaxRequest) {
 147                         ajaxRequest.onreadystatechange = ajaxBindCallback;
 148                         ajaxRequest.open("GET", url, true);
 149                         ajaxRequest.send();
 150                         }
 151                 }
 152 }