separate redis from app.js

app.js

@@ -12,41 +12,7 @@ const pug = require('pug');
 const compression = require('compression');
 const express = require('express');
 const cookieParser = require('cookie-parser');
-const r = require('redis');
-
-const redis = (() => {
-  if (!config.redis_enabled) {
-    // Stub Redis if disabled
-    return {
-      get: (_, callback) => callback(null, null),
-      setex: (_, _1, _2, callback) => callback(null),
-      on: () => {},
-    };
-  }
-
-  const redisOptions = {
-    host: '127.0.0.1',
-    port: 6379,
-  };
-
-  if (config.redis_db) {
-    redisOptions.db = config.redis_db;
-  }
-
-  if (config.redis_host) {
-    redisOptions.host = config.redis_host;
-  }
-
-  if (config.redis_port && config.redis_port > 0) {
-    redisOptions.port = config.redis_port;
-  }
-
-  if (config.redis_password) {
-    redisOptions.password = config.redis_password;
-  }
-
-  return r.createClient(redisOptions);
-})();
+const { redis } = require('./inc/redis');
 
 const nodeFetch = require('node-fetch');
 const fetch = config.http_proxy
@@ -162,12 +128,6 @@ if (config.redirect_http_to_https) {
   });
 }
 
-redis.on('error', (error) => {
-  if (error) {
-    console.error(`Redis error: ${error}`);
-  }
-});
-
 const cacheControl = require('./cacheControl.js');
 cacheControl.removeCacheFiles();
 

inc/redis.js

@@ -0,0 +1,51 @@
+const config = require('../config');
+const { promisify } = require('util');
+const r = require('redis');
+
+const redisOptions = {
+  host: '127.0.0.1',
+  port: 6379,
+};
+
+if (config.redis_db) {
+  redisOptions.db = config.redis_db;
+}
+
+if (config.redis_host) {
+  redisOptions.host = config.redis_host;
+}
+
+if (config.redis_port && config.redis_port > 0) {
+  redisOptions.port = config.redis_port;
+}
+
+if (config.redis_password) {
+  redisOptions.password = config.redis_password;
+}
+
+// Stub Redis if disabled
+const stub = {
+  get: (_, callback) => callback(null, null),
+  setex: (_, _1, _2, callback) => callback(null),
+  on: () => {},
+};
+
+const redisDisabled = !config.redis_enabled;
+
+const redis = redisDisabled ? stub : r.createClient(redisOptions);
+
+const redisAsync = {
+  get: promisify(redis.get).bind(redis),
+  setex: promisify(redis.setex).bind(redis),
+};
+
+redis.on('error', (error) => {
+  if (error) {
+    console.error(`Redis error: ${error}`);
+  }
+});
+
+module.exports = {
+  redis,
+  redisAsync,
+};