Add allKeys

lib/promise.js

@@ -475,6 +475,34 @@ exports.all = function(array){
 	return deferred.promise;
 };
 
+/**
+ * Takes a hash of promises and returns a promise that is fulfilled once all
+ * the promises in the hash keys are fulfilled
+ * @param hash	The hash of promises
+ * @return the promise that is fulfilled when all the hash keys is fulfilled, resolved to the hash of results
+ */
+exports.allKeys = function(hash){
+	var deferred = new Deferred();
+	var array = Object.keys(hash);
+	var fulfilled = 0, length = array.length;
+	var results = {};
+	if (length === 0) deferred.resolve(results);
+	else {
+		array.forEach(function(key){
+			exports.when(hash[key],
+				function(value){
+					results[key] = value;
+					fulfilled++;
+					if(fulfilled === length){
+						deferred.resolve(results);
+					}
+				},
+				deferred.reject);
+		});
+	}
+	return deferred.promise;
+};
+
 /**
  * Takes an array of promises and returns a promise that is fulfilled when the first 
  * promise in the array of promises is fulfilled