From 54a84bf130b2172f51a8283857c7608b7daabf73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bar=C4=B1=C5=9F=20Soner=20U=C5=9Fakl=C4=B1?=
 <baris@nodebb.org>
Date: Thu, 2 Nov 2017 12:56:40 -0400
Subject: [PATCH] cache fixes

---
 src/database/mongo/hash.js | 20 +++++++++++++-------
 src/groups/membership.js   | 29 +++++++++++++++++++++--------
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/src/database/mongo/hash.js b/src/database/mongo/hash.js
index becfb83a2f..aef54bf124 100644
--- a/src/database/mongo/hash.js
+++ b/src/database/mongo/hash.js
@@ -77,9 +77,10 @@ module.exports = function (db, module) {
 	};
 
 	module.getObjects = function (keys, callback) {
-		function getFromCache(next) {
-			setImmediate(next, null, keys.map(function (key) {
-				return _.clone(cache.get(key));
+		var cachedData = {};
+		function getFromCache() {
+			process.nextTick(callback, null, keys.map(function (key) {
+				return _.clone(cachedData[key]);
 			}));
 		}
 
@@ -88,7 +89,11 @@ module.exports = function (db, module) {
 		}
 
 		var nonCachedKeys = keys.filter(function (key) {
-			return cache.get(key) === undefined;
+			var data = cache.get(key);
+			if (data !== undefined) {
+				cachedData[key] = data;
+			}
+			return data === undefined;
 		});
 
 		var hits = keys.length - nonCachedKeys.length;
@@ -97,7 +102,7 @@ module.exports = function (db, module) {
 		cache.misses += misses;
 
 		if (!nonCachedKeys.length) {
-			return getFromCache(callback);
+			return getFromCache();
 		}
 
 		db.collection('objects').find({ _key: { $in: nonCachedKeys } }, { _id: 0 }).toArray(function (err, data) {
@@ -107,10 +112,11 @@ module.exports = function (db, module) {
 
 			var map = helpers.toMap(data);
 			nonCachedKeys.forEach(function (key) {
-				cache.set(key, map[key] || null);
+				cachedData[key] = map[key] || null;
+				cache.set(key, cachedData[key]);
 			});
 
-			getFromCache(callback);
+			getFromCache();
 		});
 	};
 
diff --git a/src/groups/membership.js b/src/groups/membership.js
index 42c3932805..6777edfbc9 100644
--- a/src/groups/membership.js
+++ b/src/groups/membership.js
@@ -355,8 +355,9 @@ module.exports = function (Groups) {
 		}
 
 		var cacheKey = uid + ':' + groupName;
-		if (cache.has(cacheKey)) {
-			return setImmediate(callback, null, cache.get(cacheKey));
+		var isMember = cache.get(cacheKey);
+		if (isMember !== undefined) {
+			return setImmediate(callback, null, isMember);
 		}
 
 		async.waterfall([
@@ -371,9 +372,10 @@ module.exports = function (Groups) {
 	};
 
 	Groups.isMembers = function (uids, groupName, callback) {
-		function getFromCache(next) {
-			setImmediate(next, null, uids.map(function (uid) {
-				return cache.get(uid + ':' + groupName);
+		var cachedData = {};
+		function getFromCache() {
+			setImmediate(callback, null, uids.map(function (uid) {
+				return cachedData[uid + ':' + groupName];
 			}));
 		}
 
@@ -382,7 +384,11 @@ module.exports = function (Groups) {
 		}
 
 		var nonCachedUids = uids.filter(function (uid) {
-			return !cache.get(uid + ':' + groupName);
+			var isMember = cache.get(uid + ':' + groupName);
+			if (isMember !== undefined) {
+				cachedData[uid + ':' + groupName] = isMember;
+			}
+			return isMember === undefined;
 		});
 
 		if (!nonCachedUids.length) {
@@ -395,6 +401,7 @@ module.exports = function (Groups) {
 			},
 			function (isMembers, next) {
 				nonCachedUids.forEach(function (uid, index) {
+					cachedData[uid + ':' + groupName] = isMembers[index];
 					cache.set(uid + ':' + groupName, isMembers[index]);
 				});
 
@@ -404,9 +411,10 @@ module.exports = function (Groups) {
 	};
 
 	Groups.isMemberOfGroups = function (uid, groups, callback) {
+		var cachedData = {};
 		function getFromCache(next) {
 			setImmediate(next, null, groups.map(function (groupName) {
-				return cache.get(uid + ':' + groupName);
+				return cachedData[uid + ':' + groupName];
 			}));
 		}
 
@@ -415,7 +423,11 @@ module.exports = function (Groups) {
 		}
 
 		var nonCachedGroups = groups.filter(function (groupName) {
-			return !cache.get(uid + ':' + groupName);
+			var isMember = cache.get(uid + ':' + groupName);
+			if (isMember !== undefined) {
+				cachedData[uid + ':' + groupName] = isMember;
+			}
+			return isMember === undefined;
 		});
 
 		if (!nonCachedGroups.length) {
@@ -432,6 +444,7 @@ module.exports = function (Groups) {
 			},
 			function (isMembers, next) {
 				nonCachedGroups.forEach(function (groupName, index) {
+					cachedData[uid + ':' + groupName] = isMembers[index];
 					cache.set(uid + ':' + groupName, isMembers[index]);
 				});