added memcached to metadata route, close #3

config/custom-environment-variables.json

@@ -17,6 +17,10 @@
       "dbName": "MONGODB_PROFILES_DBNAME"
     }
   },
+  "metadata": {
+    "memcachedURL": "MEMCACHED_URL",
+    "lifetime": "METADATA_CACHE_LIFETIME"
+  },
   "apiKeys": {
     "youtube": "YOUTUBE_API_KEY",
     "vimeo": "VIMEO_ACCESS_TOKEN",

config/default.json

@@ -27,6 +27,10 @@
       "dbName": "motionbank-api"
     }
   },
+  "metadata": {
+    "memcachedURL": null,
+    "lifetime": 86400
+  },
   "auth": {
     "jwks": {
       "cache": true,

package-lock.json

@@ -871,6 +871,11 @@
       "resolved": "https://registry.npmjs.org/connected/-/connected-0.0.2.tgz",
       "integrity": "sha1-e1dVshbOMf+rzMOOn04d/Bw7fG0="
     },
+    "connection-parse": {
+      "version": "0.0.7",
+      "resolved": "https://registry.npmjs.org/connection-parse/-/connection-parse-0.0.7.tgz",
+      "integrity": "sha1-GOcxiqsGppkmc3KxDFIm0locmmk="
+    },
     "contains-path": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/contains-path/-/contains-path-0.1.0.tgz",
@@ -1668,6 +1673,15 @@
       "integrity": "sha1-tdRU3CGZriJWmfNGfloH87lVuv0=",
       "dev": true
     },
+    "hashring": {
+      "version": "3.2.0",
+      "resolved": "https://registry.npmjs.org/hashring/-/hashring-3.2.0.tgz",
+      "integrity": "sha1-/aTv3oqiLNuX+x0qZeiEAeHBRM4=",
+      "requires": {
+        "connection-parse": "0.0.x",
+        "simple-lru-cache": "0.0.x"
+      }
+    },
     "hosted-git-info": {
       "version": "2.6.0",
       "resolved": "https://registry.npmjs.org/hosted-git-info/-/hosted-git-info-2.6.0.tgz",
@@ -1873,6 +1887,14 @@
       "resolved": "https://registry.npmjs.org/isstream/-/isstream-0.1.2.tgz",
       "integrity": "sha1-R+Y/evVa+m+S4VAOaQ64uFKcCZo="
     },
+    "jackpot": {
+      "version": "0.0.6",
+      "resolved": "https://registry.npmjs.org/jackpot/-/jackpot-0.0.6.tgz",
+      "integrity": "sha1-PP8GQoXL9m9OqyWTyQvOgWqCGEk=",
+      "requires": {
+        "retry": "0.6.0"
+      }
+    },
     "js-tokens": {
       "version": "3.0.2",
       "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-3.0.2.tgz",
@@ -2244,9 +2266,9 @@
       }
     },
     "mbjs-media": {
-      "version": "0.0.10",
-      "resolved": "https://registry.npmjs.org/mbjs-media/-/mbjs-media-0.0.10.tgz",
-      "integrity": "sha512-ryabEdi9G+lrdQiFg3WF3G/5Rn+Qs71RcMbgQ1+HekpUvunoirdVngCpUtygv/IW5/RxqLfBEkDNfIiQeeL2aw==",
+      "version": "0.0.11",
+      "resolved": "https://registry.npmjs.org/mbjs-media/-/mbjs-media-0.0.11.tgz",
+      "integrity": "sha512-+BNGm1jsuzZ0dznnnfkDn4dgE14xGqaFw7q2zo9lhU+z+971YEuYHhj2rqsQctzpu+ALsL7zB/4pZ/QrigZJsg==",
       "requires": {
         "axios": "^0.18.0",
         "bluebird": "^3.5.1",
@@ -2322,6 +2344,15 @@
       "resolved": "https://registry.npmjs.org/media-typer/-/media-typer-0.3.0.tgz",
       "integrity": "sha1-hxDXrwqmJvj/+hzgAWhUUmMlV0g="
     },
+    "memcached": {
+      "version": "2.2.2",
+      "resolved": "https://registry.npmjs.org/memcached/-/memcached-2.2.2.tgz",
+      "integrity": "sha1-aPhsz9hLz5PMJe1G1tf8DHUhydU=",
+      "requires": {
+        "hashring": "3.2.x",
+        "jackpot": ">=0.0.6"
+      }
+    },
     "metapak": {
       "version": "1.0.3",
       "resolved": "https://registry.npmjs.org/metapak/-/metapak-1.0.3.tgz",
@@ -2973,6 +3004,11 @@
         "signal-exit": "^3.0.2"
       }
     },
+    "retry": {
+      "version": "0.6.0",
+      "resolved": "https://registry.npmjs.org/retry/-/retry-0.6.0.tgz",
+      "integrity": "sha1-HAEHEyeab9Ho3vKK8MP/GHHKpTc="
+    },
     "rimraf": {
       "version": "2.6.2",
       "resolved": "https://registry.npmjs.org/rimraf/-/rimraf-2.6.2.tgz",
@@ -3160,6 +3196,11 @@
       "integrity": "sha1-tf3AjxKH6hF4Yo5BXiUTK3NkbG0=",
       "dev": true
     },
+    "simple-lru-cache": {
+      "version": "0.0.2",
+      "resolved": "https://registry.npmjs.org/simple-lru-cache/-/simple-lru-cache-0.0.2.tgz",
+      "integrity": "sha1-1ZzDoZPBpdAyD4Tucy9uRxPlEd0="
+    },
     "slice-ansi": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/slice-ansi/-/slice-ansi-1.0.0.tgz",

package.json

@@ -38,9 +38,10 @@
     "jwks-rsa": "^1.2.1",
     "luxon": "^1.3.3",
     "mbjs-data-models": "0.0.8",
-    "mbjs-media": "0.0.10",
+    "mbjs-media": "0.0.11",
     "mbjs-persistence": "^0.2.0",
     "mbjs-utils": "0.0.5",
+    "memcached": "^2.2.2",
     "mongodb": "^3.1.0",
     "morgan": "^1.9.0",
     "multer": "^1.3.1",

src/metadata.js

@@ -2,6 +2,8 @@ const
   config = require('config'),
   send = require('@polka/send-type'),
   TinyEmitter = require('tiny-emitter'),
+  Memcached = require('memcached'),
+  { ObjectUtil } = require('mbjs-utils'),
   { getMetaData } = require('mbjs-media/src/util/metadata')
 
 const fetchMetaData = async (annotation, user, annotationsService) => {
@@ -26,14 +28,36 @@ class Metadata extends TinyEmitter {
     super()
 
     this._annotations = annotationsService
+    if (config.metadata.memcachedURL) this._memcached = new Memcached(config.metadata.memcachedURL)
 
     const _this = this
 
     app.get('/metadata/:id', async (req, res) => {
       const result = await _this._annotations.getHandler(req)
       const annotation = result.data
+      const key = `metadata_${ObjectUtil.slug(annotation.body.source.id)}`
       if (!annotation) return _this._errorResponse(res, 404)
-      const metadata = await fetchMetaData(annotation, req.user, _this._annotations)
+      let metadata
+      if (_this._memcached) {
+        metadata = await new Promise((resolve, reject) => {
+          console.log('memcached key', key)
+          _this._memcached.get(key, function (err, data) {
+            if (err) console.error('failed to get metadata from cache', err.message)
+            resolve(data)
+          })
+        })
+      }
+      if (!metadata) {
+        metadata = await fetchMetaData(annotation, req.user, _this._annotations)
+        if (_this._memcached && metadata) {
+          await new Promise((resolve, reject) => {
+            _this._memcached.set(key, metadata, parseInt(config.metadata.lifetime.toString()), err => {
+              if (err) console.error('failed to store metadata in cache', err.message)
+              resolve()
+            })
+          })
+        }
+      }
       if (!metadata) return _this._errorResponse(res, 404)
       _this._response(req, res, metadata)
     })