First cut of the AJAX framework

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@3327 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/web/scripts/ajax.js

@@ -0,0 +1,62 @@
+//
+// Alfresco AJAX support library
+// Gavin Cornwell 14-07-2006
+//
+
+/**
+ * Makes an AJAX request to the server using POST. A text/html response
+ * is presumed.
+ *
+ * @param context The name of the application, normally "/alfresco"
+ * @param command The AJAX command to call, either 'invoke', 'get' or 'set'
+ * @param expression The managed bean expression
+ * @param callbackHandler The function to callback when the request completes
+ */
+function ajaxPostRequest(context, command, expression, callbackHandler)
+{
+   makeAjaxRequest(context, command, expression, null, callbackHandler, 
+                   "post", "text/html");
+}
+
+/**
+ * Makes an AJAX request to the server using POST.
+ *
+ * @param context The name of the application, normally "/alfresco"
+ * @param command The AJAX command to call, either 'invoke', 'get' or 'set'
+ * @param expression The managed bean expression
+ * @param parameters Set of parameters to pass with the request
+ * @param callbackHandler The function to callback when the request completes
+ * @param method The HTTP method to use for the request either "get" or "post"
+ * @param contentType The mimetype to expect from the server
+ */
+function makeAjaxRequest(context, command, expression, parameters, 
+                         callbackHandler, method, contentType)
+{
+   // use dojo to do the actual work
+   dojo.io.bind({
+      method: method,
+      url: context + "/ajax/" + command + "/" + expression,
+      content: parameters,
+      load: callbackHandler,
+      error: handleErrorDojo,
+      mimetype: contentType
+   });
+}
+
+/**
+ * Default handler for errors
+ */
+function handleErrorDojo(type, errObj)
+{
+   // remove the dojo prefix from the message
+   var errorStart = "XMLHttpTransport Error: 500 ";
+   var msg = errObj.message;
+   
+   if (msg.indexOf(errorStart) != -1)
+   {
+      msg = msg.substring(errorStart.length);
+   }
+   
+   // TODO: Show a nicer error page, an alert will do for now!
+   alert(msg);
+}