Changeset 1904

Timestamp:

11/18/06 09:42:35 (2 years ago)

Author:

crschmidt

Message:

non-deterministic server choice is a bad idea. When I view a tile, I may get caching
headers with that URL from a properly configured server. By randomly changing the
server I request from, the browser has to store up to numUrls caches for each tile.
Instead, make this deterministic based on the integer value of the request parameters,
modded into the severs array. Deployed on labs.metacarta.com/wms-c/demo.html.

Files:

• sandbox/crschmidt/multiserverwms/lib/OpenLayers/Layer/HTTPRequest.js (modified) (2 diffs)

sandbox/crschmidt/multiserverwms/lib/OpenLayers/Layer/HTTPRequest.js

@@ -110 +110 @@
-        var url = (altUrl == null) ? this.url : altUrl;
-        
-        if (typeof url == "object") {
-            url = url[Math.floor(Math.random()*url.length)];
-        }   
-        // requestString always starts with url
-        var requestString = url;        
-
-        // create a new params hashtable with all the layer params and the 
-        // new params together. then convert to string
@@ -121 +115 @@
-        var allParams = OpenLayers.Util.extend(allParams, newParams);
-        var paramsString = OpenLayers.Util.getParameterString(allParams);
+        if (typeof url == "object") {
+            var serverid=0;
+            for (var i=0; i<paramsString.length; i++) { 
+              serverid += paramsString.charCodeAt(i); 
+            }
+            url = url[serverid%url.length];
+        }   
+        
+        // requestString always starts with url
+        var requestString = url;        
+        
-        if (paramsString != "") {
-            var lastServerChar = url.charAt(url.length - 1);