Consolidate request method API (close snowplow#700)

Author: mmathias01

src/js/out_queue.js

@@ -51,21 +51,29 @@
 	 * @param object mutSnowplowState Gives the pageUnloadGuard a reference to the outbound queue
 	 *                                so it can unload the page when all queues are empty
 	 * @param boolean useLocalStorage Whether to use localStorage at all
-	 * @param boolean usePost Whether to send events by POST or GET
+	 * @param string eventMethod if null will use 'beacon' otherwise can be set to 'post', 'get', or 'beacon' to force. 
 	 * @param int bufferSize How many events to batch in localStorage before sending them all.
 	 *                       Only applies when sending POST requests and when localStorage is available.
 	 * @param int maxPostBytes Maximum combined size in bytes of the event JSONs in a POST request
 	 * @param string postPath The path where events are to be posted
 	 * @return object OutQueueManager instance
 	 */
-	object.OutQueueManager = function (functionName, namespace, mutSnowplowState, useLocalStorage, useBeacon, usePost, postPath, bufferSize, maxPostBytes) {
+	object.OutQueueManager = function (functionName, namespace, mutSnowplowState, useLocalStorage, eventMethod, postPath, bufferSize, maxPostBytes) {
 		var	queueName,
 			executingQueue = false,
 			configCollectorUrl,
 			outQueue;
-
-		useBeacon = useBeacon && navigator && navigator.sendBeacon;
-
+		
+		//Force to lower case if its a string
+		eventMethod = eventMethod.toLowerCase ? eventMethod.toLowerCase() : eventMethod;
+		
+		//Use the Beacon API if eventMethod is set null, true, or 'beacon'. 
+		var enableBeacon = (eventMethod === null || eventMethod === true || eventMethod === "beacon" || eventMethod === "true") ? true : false;
+		// Fall back to POST or GET for browsers which don't support Beacon API
+		useBeacon = enableBeacon && navigator && navigator.sendBeacon;
+
+		//Use POST if specified, or beacon is unavailable. 
+		var usePost = (eventMethod === "post" || (enableBeacon && !useBeacon)) ? true : false;
 		// Fall back to GET for browsers which don't support CORS XMLHttpRequests (e.g. IE <= 9)
 		usePost = usePost && window.XMLHttpRequest && ('withCredentials' in new XMLHttpRequest());
 

src/js/tracker.js

@@ -76,21 +76,32 @@
 	 * 12. useCookies, true
 	 * 13. sessionCookieTimeout, 1800
 	 * 14. contexts, {}
-	 * 15. beacon, false
-	 * 16. post, false
-	 * 17. bufferSize, 1
-	 * 18. crossDomainLinker, false
-	 * 19. maxPostBytes, 40000
-	 * 20. discoverRootDomain, false
-	 * 21. cookieLifetime, 63072000
-	 * 22. stateStorageStrategy, 'cookieAndLocalStorage'
+	 * 15. eventMethod, 'beacon'
+	 * 16. post, false *DEPRECATED use eventMethod instead*
+	 * 17. postPath, null
+	 * 18. bufferSize, 1
+	 * 19. crossDomainLinker, false
+	 * 20. maxPostBytes, 40000
+	 * 21. discoverRootDomain, false
+	 * 22. cookieLifetime, 63072000
+	 * 23. stateStorageStrategy, 'cookieAndLocalStorage'
 	 */
 	object.Tracker = function Tracker(functionName, namespace, version, mutSnowplowState, argmap) {
 
 		/************************************************************
 		 * Private members
 		 ************************************************************/
-		var
+		 
+		 var argmap = argmap || {};
+		 
+		 //use POST if that property is present on the argmap
+		 if(argmap.hasOwnProperty('post')) {
+			 argmap.eventMethod = argmap.post === true ? 'post' : 'get';
+		 } else {
+			 argmap.eventMethod = argmap.eventMethod || 'beacon'
+		 }
+
+		 var
 			// Tracker core
 			core = coreConstructor(true, function(payload) {
 				addBrowserData(payload);
@@ -127,8 +138,6 @@
 
 			customReferrer,
 
-			argmap = argmap || {},
-
 			// Request method is always GET for Snowplow
 			configRequestMethod = 'GET',
 
@@ -297,8 +306,7 @@
 				mutSnowplowState,
 				configStateStorageStrategy == 'localStorage' ||
 					configStateStorageStrategy == 'cookieAndLocalStorage',
-				argmap.beacon,
-				argmap.post,
+				argmap.eventMethod,
 				configPostPath,
 				argmap.bufferSize,
 				argmap.maxPostBytes || 40000),