Push scalability (#3080)

* Update status through increment
* adds support for incrementing nested keys
* fix issue when having spaces in keys for ordering
* Refactors PushController to use worker
* Adds tests for custom push queue config
* Makes PushController adapter independant
* Better logging of _PushStatus in VERBOSE

src/Push/utils.js

@@ -0,0 +1,30 @@
+import Parse from 'parse/node';
+
+export function isPushIncrementing(body) {
+  return body.data &&
+         body.data.badge &&
+         typeof body.data.badge == 'string' &&
+         body.data.badge.toLowerCase() == "increment"
+}
+
+/**
+ * Check whether the deviceType parameter in qury condition is valid or not.
+ * @param {Object} where A query condition
+ * @param {Array} validPushTypes An array of valid push types(string)
+ */
+export function validatePushType(where = {}, validPushTypes = []) {
+  var deviceTypeField = where.deviceType || {};
+  var deviceTypes = [];
+  if (typeof deviceTypeField === 'string') {
+    deviceTypes.push(deviceTypeField);
+  } else if (Array.isArray(deviceTypeField['$in'])) {
+    deviceTypes.concat(deviceTypeField['$in']);
+  }
+  for (var i = 0; i < deviceTypes.length; i++) {
+    var deviceType = deviceTypes[i];
+    if (validPushTypes.indexOf(deviceType) < 0) {
+      throw new Parse.Error(Parse.Error.PUSH_MISCONFIGURED,
+                            deviceType + ' is not supported push type.');
+    }
+  }
+}