Add new method to RequestProcessor called before the request is processed,...

Add new method to RequestProcessor called before the request is processed, manipulateRequest(). Allows plugins to change the request before it is processed.

core/Tracker/RequestProcessor.php

@@ -35,12 +35,15 @@ use Piwik\Tracker\Visit\VisitProperties;
  * When Piwik handles a single tracking request, it gathers all available RequestProcessors and
  * invokes their methods in sequence.
  *
- * The first method called is {@link self::processRequestParams()}. RequestProcessors should use
+ * The first method called is {@link self::manipulateRequest()}. By default this is a no-op, but
+ * RequestProcessors can use it to manipulate tracker requests before they are processed.
+ *
+ * The second method called is {@link self::processRequestParams()}. RequestProcessors should use
  * this method to compute request metadata and set visit properties using the tracking request.
  * An example includes the ActionRequestProcessor, which uses this method to determine the action
  * being tracked.
  *
- * The second method called is {@link self::afterRequestProcessed()}. RequestProcessors should
+ * The third method called is {@link self::afterRequestProcessed()}. RequestProcessors should
  * use this method to either compute request metadata/visit properties using other plugins'
  * request metadata, OR override other plugins' request metadata to tweak tracker behavior.
  * An example of the former can be seen in the GoalsRequestProcessor which uses the action
@@ -48,7 +51,7 @@ use Piwik\Tracker\Visit\VisitProperties;
  * conversions. An example of the latter can be seen in the PingRequestProcessor, which on
  * ping requests, aborts conversion recording and new visit recording.
  *
- * After these two methods are called, either {@link self::onNewVisit()} or {@link self::onExistingVisit()}
+ * After these methods are called, either {@link self::onNewVisit()} or {@link self::onExistingVisit()}
  * is called. Generally, plugins should favor defining Dimension classes instead of using these methods,
  * however sometimes it is not possible (as is the case with the CustomVariables plugin).
  *
@@ -83,6 +86,19 @@ abstract class RequestProcessor
     /**
      * This is the first method called when processing a tracker request.
      *
+     * Derived classes can use this method to manipulate a tracker request before the request
+     * is handled. Plugins could change the URL, add custom variables, etc.
+     *
+     * @param Request $request
+     */
+    public function manipulateRequest(Request $request)
+    {
+        // empty
+    }
+
+    /**
+     * This is the second method called when processing a tracker request.
+     *
      * Derived classes should use this method to set request metadata based on the tracking
      * request alone. They should not try to access request metadata from other plugins,
      * since they may not be set yet.
@@ -99,7 +115,7 @@ abstract class RequestProcessor
     }
 
     /**
-     * This is the second method called when processing a tracker request.
+     * This is the third method called when processing a tracker request.
      *
      * Derived classes should use this method to set request metadata that needs request metadata
      * from other plugins, or to override request metadata from other plugins to change

core/Tracker/Visit.php

@@ -113,6 +113,12 @@ class Visit implements VisitInterface
      */
     public function handle()
     {
+        foreach ($this->requestProcessors as $processor) {
+            Common::printDebug("Executing " . get_class($processor) . "::manipulateRequest()...");
+
+            $processor->manipulateRequest($this->request);
+        }
+
         $this->visitProperties = new VisitProperties();
 
         foreach ($this->requestProcessors as $processor) {