Expiration

lib/memjsCache.js

@@ -1,48 +1,58 @@
 
 var MemJS = require("memjs").Client;
 
-memjs = MemJS.create();
+var memjs = MemJS.create();
 
 var cache_manager = require('cache-manager');
 
+var pageTTL = process.env.PAGE_TTL || 0;
+
 console.log('using memjs cache');
 
 module.exports = {
-    init: function() {
-        this.cache = cache_manager.caching({
-            store: memjs_cache
-        });
-    },
-
-    beforePhantomRequest: function(req, res, next) {
-        if(req.method !== 'GET') {
-            return next();
-        }
-
-        this.cache.get(req.prerender.url, function (err, result) {
-            if (!err && result) {
-                res.send(200, result);
-            } else {
-                next();
-            }
-        });
-    },
-
-    afterPhantomRequest: function(req, res, next) {
-        this.cache.set(req.prerender.url, req.prerender.documentHTML);
+  init: function() {
+    this.cache = cache_manager.caching({
+      store: memjs_cache
+    });
+  },
+
+  beforePhantomRequest: function(req, res, next) {
+    if (req.method !== 'GET') {
+      return next();
+    }
+    //console.log('[memjs cache] gettting page from cache with an URL ', req.prerender.url);
+
+    this.cache.get(req.prerender.url, function(err, result) {
+      if (!err && result) {
+        //console.log('[memjs cache] successfully got page from cache');
+        res.send(200, result);
+      } else {
+        //console.log('[memjs cache] no such page in cache');
         next();
+      }
+    });
+  },
+
+  afterPhantomRequest: function(req, res, next) {
+    // Cache only pages with status code 200. This is to avoid caching of 3xx/4xx/5xx status codes
+    if (req.prerender.statusCode === 200) {
+      //console.log('[memjs cache] saving page with  pageTTL ', pageTTL, ' and URL ', req.prerender.url);
+      this.cache.set(req.prerender.url, req.prerender.documentHTML, function(err, val) {}, pageTTL);
     }
+    next();
+  }
+
 };
 
 
 var memjs_cache = {
-    get: function(key, callback) {
-      memjs.get(key, function(err, value) {
-        var stringValue = value ? value.toString() : null;
-        callback(err, stringValue);
-      });
-    },
-    set: function(key, value, callback) {
-      memjs.set(key, value, callback);
-    }
+  get: function(key, callback) {
+    memjs.get(key, function(err, value) {
+      var stringValue = value ? value.toString() : null;
+      callback(err, stringValue);
+    });
+  },
+  set: function(key, value, callback, ttl) {
+    memjs.set(key, value, callback, ttl);
+  }
 };