Fix MapServer request string handling by overriding getFullRequestUrl(). Fixes #508.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@2544 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/MapServer.js

@@ -86,16 +86,84 @@ OpenLayers.Layer.MapServer.prototype =
      */
     getURL: function (bounds) {
         
+        // Make a list, so that getFullRequestString uses literal "," 
+        var extent = [bounds.left, bounds. bottom, bounds.right, bounds.top];
+        
+        // make lists, so that literal ','s are used 
         var url = this.getFullRequestString(
-                     {mapext:bounds.toBBOX().replace(/,/g,"+"),
-                      imgext:bounds.toBBOX().replace(/,/g,"+"),
-                      map_size:this.tileSize.w+'+'+this.tileSize.h,
+                     {mapext:   extent,
+                      imgext:   extent,
+                      map_size: [this.tileSize.w,this.tileSize.h],
                       imgx:     this.tileSize.w/2,
                       imgy:     this.tileSize.h/2,
-                      imgxy: this.tileSize.w+"+"+this.tileSize.h
+                      imgxy:    [this.tileSize.w,this.tileSize.h]
                       });
+        
         return url;
     },
+    
+    /** 
+     * getFullRequestString on MapServer layers is special, because we 
+     * do a regular expression replace on ',' in parameters to '+'.
+     * This is why it is subclassed here.
+     *
+     * @param {Object} newParams Parameters to add to the default parameters
+     *                           for the layer.
+     * @param {String} altUrl    Alternative base URL to use.
+     */
+    getFullRequestString:function(newParams, altUrl) {
+        
+    
+        // 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(new Object(), this.params);
+        allParams = OpenLayers.Util.extend(allParams, newParams);
+        // ignore parameters that are already in the url search string
+        var urlParams = OpenLayers.Util.upperCaseObject(
+                            OpenLayers.Util.getArgs(url));
+        for(var key in allParams) {
+            if(key.toUpperCase() in urlParams) {
+                delete allParams[key];
+            }
+        }
+        var paramsString = OpenLayers.Util.getParameterString(allParams);
+        
+        /* 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
+           leave ',' only in the case of list items (since otherwise it is
+           encoded) then do a regular expression replace on the , characters
+           to '+' */
+        paramsString = paramsString.replace(/,/g, "+");
+        
+        if (paramsString != "") {
+            var lastServerChar = url.charAt(url.length - 1);
+            if ((lastServerChar == "&") || (lastServerChar == "?")) {
+                requestString += paramsString;
+            } else {
+                if (url.indexOf('?') == -1) {
+                    //serverPath has no ? -- add one
+                    requestString += '?' + paramsString;
+                } else {
+                    //serverPath contains ?, so must already have paramsString at the end
+                    requestString += '&' + paramsString;
+                }
+            }
+        }
+        return requestString;
+    },
     /** @final @type String */
     CLASS_NAME: "OpenLayers.Layer.MapServer"
 });