Ticket #803: mapserver_deterministic_url.patch

tests/Layer/test_MapServer.html

@@ -156 +156 @@
-    }
-
-    function test_07_Layer_MapServer_getFullRequestString (t) {
-
-
-
+
-        var map = new OpenLayers.Map('map');
-        tUrl = "http://labs.metacarta.com/cgi-bin/mapserv";
-        tParams = { layers: 'basic', 
@@ -178 +176 @@
-        
-        t.eq(str, sStr , "getFullRequestString() works");
-        map.destroy();
+        
+        tUrl = ["http://octo.metacarta.com/cgi-bin/mapserv","http://labs.metacarta.com/cgi-bin/mapserv"];
+        layer = new OpenLayers.Layer.MapServer(name, tUrl, tParams, null);
+        str = layer.getFullRequestString({'c':'d'});
+        t.eq(str, tUrl[1] + '?' + OpenLayers.Util.getParameterString(OpenLayers.Util.extend(tParams,{'c':'d'})), "getFullRequestString() works for list of two urls and is deterministic");
+        layer.destroy();
+        var tParams = {
+                 layers: 'basic', 
+                 format: 'png',
+                 mode: 'map',
+                 map_imagetype: 'png'
+        };
+        tUrl = ["http://octo.metacarta.com/cgi-bin/mapserv","http://labs.metacarta.com/cgi-bin/mapserv"];
+        layer = new OpenLayers.Layer.MapServer(name, tUrl, tParams, null);
+        str = layer.getFullRequestString({'a':'b'});
+        t.eq(str, tUrl[0] + '?' + OpenLayers.Util.getParameterString(OpenLayers.Util.extend(tParams,{'a':'b'})), "getFullRequestString() works for list of two urls and is deterministic");
+        layer.destroy();
-
-    }
-

lib/OpenLayers/Layer/MapServer.js

@@ -142 +142 @@
-        // use layer's url unless altUrl passed in
-        var url = (altUrl == null) ? this.url : altUrl;
-        
-        // if url is not a string, it should be an array of strings, 
-        //  in which case we will randomly select one of them in order
-        //  to evenly distribute requests to different urls.
-        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
-        var allParams = OpenLayers.Util.extend({}, this.params);
-        allParams = OpenLayers.Util.extend(allParams, newParams);
+        var paramsString = OpenLayers.Util.getParameterString(allParams);
+        
+        // if url is not a string, it should be an array of strings, 
+        // in which case we will deterministically select one of them in 
+        // order to evenly distribute requests to different urls.
+        if (url instanceof Array) {
+            url = this.selectUrl(paramsString, url);
+        }   
+        
-        // ignore parameters that are already in the url search string
-        var urlParams = OpenLayers.Util.upperCaseObject(
-                            OpenLayers.Util.getParameters(url));
@@ -163 +163 @@
-                delete allParams[key];
-            }
-        }
-var 
+
-        
+        // requestString always starts with url
+        var requestString = url;        
+
-        // MapServer needs '+' seperating things like bounds/height/width.
-        //   Since typically this is URL encoded, we use a slight hack: we
-        //  depend on the list-like functionality of getParameterString to