From 84f297b40035f08e9a09a4a7dbc4cb907cae82a1 Mon Sep 17 00:00:00 2001
From: MICHAEL JACKSON <mjijackson@gmail.com>
Date: Thu, 25 May 2017 11:53:47 -0700
Subject: [PATCH] Use SETEX for storing package.json configs

Also, remove option for in-memory cache.
---
 package.json                       |  1 -
 server/index.js                    |  1 -
 server/middleware/RegistryCache.js | 60 +++++++++++-------------------
 server/middleware/RegistryUtils.js | 12 +++---
 yarn.lock                          |  4 +-
 5 files changed, 29 insertions(+), 49 deletions(-)

diff --git a/package.json b/package.json
index b067411..5783cf5 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,6 @@
     "http-client": "^4.3.1",
     "invariant": "^2.2.2",
     "isomorphic-fetch": "^2.2.1",
-    "lru-cache": "^4.0.2",
     "mime": "^1.3.6",
     "mkdirp": "^0.5.1",
     "morgan": "^1.8.1",
diff --git a/server/index.js b/server/index.js
index 4c9701d..273f3d9 100644
--- a/server/index.js
+++ b/server/index.js
@@ -106,7 +106,6 @@ const defaultServerConfig = {
   registryURL: process.env.REGISTRY_URL || 'https://registry.npmjs.org',
   redirectTTL: process.env.REDIRECT_TTL || 500,
   autoIndex: !process.env.DISABLE_INDEX,
-  redisURL: process.env.REDIS_URL,
   blacklist: require('./package-blacklist').blacklist
 }
 
diff --git a/server/middleware/RegistryCache.js b/server/middleware/RegistryCache.js
index 3e957e2..65e1fa0 100644
--- a/server/middleware/RegistryCache.js
+++ b/server/middleware/RegistryCache.js
@@ -1,49 +1,33 @@
 const redis = require('redis')
-const createLRUCache = require('lru-cache')
+const invariant = require('invariant')
 
-const createRedisCache = (redisURL) => {
-  const client = redis.createClient(redisURL)
+const RedisURL = process.env.REDIS_URL
 
-  const createKey = (key) => 'registry:' + key
+invariant(
+  RedisURL,
+  'Missing $REDIS_URL environment variable'
+)
 
-  const set = (key, value, expiry) => {
-    client.set(createKey(key), JSON.stringify(value))
-    client.pexpire(createKey(key), expiry)
-  }
+const db = redis.createClient(RedisURL)
 
-  const get = (key, callback) => {
-    client.get(createKey(key), (error, value) => {
-      callback(error, value && JSON.parse(value))
-    })
-  }
+const createKey = (key) => 'registryCache-' + key
 
-  const del = (key) => {
-    client.del(createKey(key))
-  }
-
-  return { set, get, del }
+const set = (key, value, expiry) => {
+  db.setex(createKey(key), expiry, JSON.stringify(value))
 }
 
-const createMemoryCache = (options) => {
-  const cache = createLRUCache(options)
-
-  const set = (key, value, expiry) => {
-    cache.set(key, value, expiry)
-  }
-
-  const get = (key, callback) => {
-    callback(null, cache.get(key))
-  }
-
-  const del = (key) => {
-    cache.del(key)
-  }
-
-  return { set, get, del }
+const get = (key, callback) => {
+  db.get(createKey(key), (error, value) => {
+    callback(error, value && JSON.parse(value))
+  })
 }
 
-const RegistryCache = process.env.REDIS_URL
-  ? createRedisCache(process.env.REDIS_URL)
-  : createMemoryCache({ max: 1000 })
+const del = (key) => {
+  db.del(createKey(key))
+}
 
-module.exports = RegistryCache
+module.exports = {
+  set,
+  get,
+  del
+}
diff --git a/server/middleware/RegistryUtils.js b/server/middleware/RegistryUtils.js
index f67316d..a5aa752 100644
--- a/server/middleware/RegistryUtils.js
+++ b/server/middleware/RegistryUtils.js
@@ -21,13 +21,10 @@ const getPackageInfoFromRegistry = (registryURL, packageName) => {
   ))
 }
 
-const OneMinute = 60 * 1000
 const PackageNotFound = 'PackageNotFound'
 
 const getPackageInfo = (registryURL, packageName, callback) => {
-  const cacheKey = registryURL + packageName
-
-  RegistryCache.get(cacheKey, (error, value) => {
+  RegistryCache.get(packageName, (error, value) => {
     if (error) {
       callback(error)
     } else if (value) {
@@ -39,15 +36,16 @@ const getPackageInfo = (registryURL, packageName, callback) => {
           // from making unnecessary requests to the registry for
           // bad package names. In the worst case, a brand new
           // package's info will be available within 5 minutes.
-          RegistryCache.set(cacheKey, PackageNotFound, OneMinute * 5)
+          RegistryCache.set(packageName, PackageNotFound, 300)
         } else {
-          RegistryCache.set(cacheKey, value, OneMinute)
+          // Keep package.json in the cache for a minute.
+          RegistryCache.set(packageName, value, 60)
         }
 
         callback(null, value)
       }, error => {
         // Do not cache errors.
-        RegistryCache.del(cacheKey)
+        RegistryCache.del(packageName)
         callback(error)
       })
     }
diff --git a/yarn.lock b/yarn.lock
index 572817d..0372940 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1529,7 +1529,7 @@ debug@2.6.7:
   dependencies:
     ms "2.0.0"
 
-debug@2.6.8, debug@^2.1.0, debug@^2.1.1, debug@^2.2.0, debug@^2.6.0, debug@^2.6.3, debug@^2.6.6, debug@^2.6.8:
+debug@2.6.8, debug@^2.1.0, debug@^2.1.1, debug@^2.2.0, debug@^2.6.0, debug@^2.6.3, debug@^2.6.6:
   version "2.6.8"
   resolved "https://registry.yarnpkg.com/debug/-/debug-2.6.8.tgz#e731531ca2ede27d188222427da17821d68ff4fc"
   dependencies:
@@ -3383,7 +3383,7 @@ lower-case@^1.1.1:
   version "1.1.4"
   resolved "https://registry.yarnpkg.com/lower-case/-/lower-case-1.1.4.tgz#9a2cabd1b9e8e0ae993a4bf7d5875c39c42e8eac"
 
-lru-cache@^4.0.1, lru-cache@^4.0.2:
+lru-cache@^4.0.1:
   version "4.0.2"
   resolved "https://registry.yarnpkg.com/lru-cache/-/lru-cache-4.0.2.tgz#1d17679c069cda5d040991a09dbc2c0db377e55e"
   dependencies: