waterfall for topics

src/topics.js

@@ -107,7 +107,7 @@ var async = require('async'),
 	Topics.getCategoryData = function(tid, callback) {
 		Topics.getTopicField(tid, 'cid', function(err, cid) {
 			if (err) {
-				callback(err);
+				return callback(err);
 			}
 
 			categories.getCategoryData(cid, callback);
@@ -144,7 +144,13 @@ var async = require('async'),
 			return callback(null, []);
 		}
 
-		Topics.getTopicsData(tids, function(err, topics) {
+		var uids, cids, topics;
+
+		async.waterfall([
+			function(next) {
+				Topics.getTopicsData(tids, next);
+			},
+			function(_topics, next) {
 				function mapFilter(array, field) {
 					return array.map(function(topic) {
 						return topic && topic[field] && topic[field].toString();
@@ -153,17 +159,11 @@ var async = require('async'),
 					});
 				}
 
-			if (err) {
-				return callback(err);
-			}
-
-			var uids = mapFilter(topics, 'uid');
-			var cids = mapFilter(topics, 'cid');
+				topics = _topics;
+				uids = mapFilter(topics, 'uid');
+				cids = mapFilter(topics, 'cid');
 
 				async.parallel({
-				teasers: function(next) {
-					Topics.getTeasers(topics, next);
-				},
 					users: function(next) {
 						user.getMultipleUserFields(uids, ['uid', 'username', 'userslug', 'picture'], next);
 					},
@@ -173,14 +173,15 @@ var async = require('async'),
 					hasRead: function(next) {
 						Topics.hasReadTopics(tids, uid, next);
 					},
+					teasers: function(next) {
+						Topics.getTeasers(topics, next);
+					},
 					tags: function(next) {
 						Topics.getTopicsTagsObjects(tids, next);
 					}
-			}, function(err, results) {
-				if (err) {
-					return callback(err);
-				}
-
+				}, next);
+			},
+			function(results, next) {
 				var users = _.object(uids, results.users);
 				var categories = _.object(cids, results.categories);
 
@@ -204,17 +205,24 @@ var async = require('async'),
 					return topic &&	topic.category && !topic.category.disabled;
 				});
 
-				plugins.fireHook('filter:topics.get', {topics: topics, uid: uid}, function(err, topicData) {
-					callback(err, topicData.topics);
-				});
-			});
-		});
+				plugins.fireHook('filter:topics.get', {topics: topics, uid: uid}, next);
+			},
+			function(data, next) {
+				next(null, data.topics);
+			}
+		], callback);
 	};
 
 	Topics.getTopicWithPosts = function(tid, set, uid, start, stop, reverse, callback) {
-		Topics.getTopicData(tid, function(err, topicData) {
-			if (err || !topicData) {
-				return callback(err || new Error('[[error:no-topic]]'));
+		var topicData;
+		async.waterfall([
+			function(next) {
+				Topics.getTopicData(tid, next);
+			},
+			function(_topicData, next) {
+				topicData = _topicData;
+				if (!topicData) {
+					return callback(new Error('[[error:no-topic]]'));
 				}
 
 				async.parallel({
@@ -224,11 +232,9 @@ var async = require('async'),
 					tags: async.apply(Topics.getTopicTagsObjects, tid),
 					isFollowing: async.apply(Topics.isFollowing, [tid], uid),
 					bookmark: async.apply(Topics.getUserBookmark, tid, uid)
-			}, function(err, results) {
-				if (err) {
-					return callback(err);
-				}
-
+				}, next);
+			},
+			function(results, next) {
 				topicData.posts = results.posts;
 				topicData.category = results.category;
 				topicData.thread_tools = results.threadTools.tools;
@@ -241,11 +247,12 @@ var async = require('async'),
 				topicData.locked = parseInt(topicData.locked, 10) === 1;
 				topicData.pinned = parseInt(topicData.pinned, 10) === 1;
 
-				plugins.fireHook('filter:topic.get', {topic: topicData, uid: uid}, function(err, data) {
-					callback(err, data ? data.topic : null);
-				});
-			});
-		});
+				plugins.fireHook('filter:topic.get', {topic: topicData, uid: uid}, next);
+			},
+			function(data, next) {
+				next(null, data.topic);
+			}
+		], callback);
 	};
 
 	function getMainPostAndReplies(topic, set, uid, start, stop, reverse, callback) {

src/topics/user.js

@@ -2,7 +2,8 @@
 
 'use strict';
 
-var db = require('../database'),
+var async = require('async'),
+	db = require('../database'),
 	posts = require('../posts');
 
 
@@ -19,24 +20,22 @@ module.exports = function(Topics) {
 	};
 
 	Topics.getUids = function(tid, callback) {
-		Topics.getPids(tid, function(err, pids) {
-			if (err) {
-				return callback(err);
-			}
-
-			posts.getPostsFields(pids, ['uid'], function(err, postData) {
-				if (err) {
-					return callback(err);
-				}
-
+		async.waterfall([
+			function(next) {
+				Topics.getPids(tid, next);
+			},
+			function(pids, next) {
+				posts.getPostsFields(pids, ['uid'], next);
+			},
+			function(postData, next) {
 				var uids = postData.map(function(post) {
 					return post && post.uid;
 				}).filter(function(uid, index, array) {
-					return array.indexOf(uid) === index;
+					return uid && array.indexOf(uid) === index;
 				});
 
-				callback(null, uids);
-			});
-		});
+				next(null, uids);
+			}
+		], callback);
 	};
 };