banner rotating uses srandmember from redis of board banners

db/boards.js

@@ -9,21 +9,32 @@ module.exports = {
 	db,
 
 	findOne: async (name) => {
-		const cacheKey = `board_${name}`;
-		let board = await cache.get(cacheKey);
+		let board = await cache.get(`board_${name}`);
 		if (board && board !== 'no_exist') {
 			return board;
 		} else {
 			board = await db.findOne({ '_id': name });
 			if (board) {
-				cache.set(cacheKey, board);
+				cache.set(`board_${name}`, board);
+				cache.sadd(`banners_${name}`, board.banners);
 			} else {
-				cache.set(cacheKey, 'no_exist', 'ex', 3600); //1 hour expiry just so it doesnt grow indefinitely
+				cache.set(`board_${name}`, 'no_exist', 'ex', 3600); //1 hour expiry just so it doesnt grow indefinitely
 			}
 		}
 		return board;
 	},
 
+	randomBanner: async (name) => {
+		let banner = await cache.srand(`banners_${name}`);
+		if (!banner) {
+			const board = await module.exports.findOne(name);
+			if (board) {
+				banner = board.banners[Math.floor(Math.random()*board.banners.length)];
+			}
+		}
+		return banner;
+	},
+
 	setOwner: (board, username) => {
 		cache.del(`board_${board}`);
 		return db.updateOne({
@@ -46,15 +57,21 @@ module.exports = {
 
 	deleteOne: (board) => {
 		cache.del(`board_${board}`);
+		cache.del(`banners_${board}`);
 		return db.deleteOne({ '_id': board });
 	},
 
 	deleteAll: (board) => {
+		/*
+			no clearing redis cache here, will leave that up to gulpfile, since this happens in the
+			wipe script, it would delete redis cache for everything, not just boards
+		*/
 		return db.deleteMany({});
 	},
 
 	removeBanners: (board, filenames) => {
 		cache.del(`board_${board}`);
+		cache.del(`banners_${board}`);
 		return db.updateOne(
 			{
 				'_id': board,
@@ -68,6 +85,7 @@ module.exports = {
 
 	addBanners: (board, filenames) => {
 		cache.del(`board_${board}`);
+		cache.del(`banners_${board}`);
 		return db.updateOne(
 			{
 				'_id': board,
@@ -112,7 +130,6 @@ module.exports = {
 	},
 
 	getNextId: async (board) => {
-		//cache.del(`board_${board}`); //dont need to clear cache for this? only time this value is used, its fetched from db.
 		const increment = await db.findOneAndUpdate(
 			{
 				'_id': board

models/pages/randombanner.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const Boards = require(__dirname+'/../../db/boards.js');
+const Boards = require(__dirname+'/../../db/boards.js')
 
 module.exports = async (req, res, next) => {
 
@@ -8,27 +8,18 @@ module.exports = async (req, res, next) => {
 		return next();
 	}
 
-	//agregate to get single random item from banners array
-	const board = await Boards.db.aggregate([
-		{
-			'$match': {
-				'_id': req.query.board
-			}
-		},
-		{
-			'$unwind': '$banners'
-		},
-		{
-			'$sample': {
-				'size' : 1
-			}
-		}
-	]).toArray().then(res => res[0]);
+	let banner;
+	try {
+		banner = await Boards.randomBanner(req.query.board);
+	} catch (err) {
+		return next(err);
+	}
 
-	if (board && board.banners != null) {
-		return res.redirect(`/banner/${req.query.board}/${board.banners}`);
+	if (!banner) {
+		//non existing boards will show default banner, but it doesnt really matter.
+		return res.redirect('/img/defaultbanner.png');
 	}
 
-	return res.redirect('/img/defaultbanner.png');
+	return res.redirect(`/banner/${req.query.board}/${banner}`);
 
 }

redis.js

@@ -8,17 +8,29 @@ module.exports = {
 
 	redisClient: client,
 
-//cache not used yet, but will need to JSON stringify things that are objects e.g. boards, threads 
+	//get a value with key
 	get: async (key) => {
 		return client.get(key).then(res => {
 			return JSON.parse(res);
 		});
 	},
 
+	//set a value on key
 	set: (key, value) => {
 		return client.set(key, JSON.stringify(value));
 	},
 
+	//add items to a set
+	sadd: (key, value) => {
+		return client.sadd(key, value);
+	},
+
+	//get random item from set
+	srand: (key) => {
+		return client.srandmember(key);
+	},
+
+	//delete value with key
 	del: (key) => {
 		return client.del(key);
 	},