Cache json endpoints (#348)

* Faster first render

* Cache json endpoint requests. Fixes #298

* feedback

common.py

@@ -63,8 +63,16 @@ class JSONHandler(BaseHandler):
 
     return data
 
-  def get(self, data, formatted=False):
+  def get(self, data, formatted=False, public=True):
+    cache_type = 'public'
+    if not public:
+      cache_type = 'private'
+
+    # Cache script generated json responses.
+    self.response.headers['Cache-Control'] = '%s, max-age=%s' % (
+        cache_type, settings.DEFAULT_CACHE_TIME)
     self.response.headers['Content-Type'] = 'application/json;charset=utf-8'
+
     if formatted:
       return self.response.write(json.dumps(data, separators=(',',':')))
     else:

metrics.py

@@ -59,7 +59,9 @@ class TimelineHandler(common.JSONHandler):
       memcache.set(KEY, data, time=CACHE_AGE)
 
     data = self._clean_data(data)
-    super(TimelineHandler, self).get(data)
+    # Metrics json shouldn't be cached by intermediary caches because users
+    # see different data when logged in. Set Cache-Control: private.
+    super(TimelineHandler, self).get(data, public=False)
 
 
 class PopularityTimelineHandler(TimelineHandler):
@@ -114,7 +116,9 @@ class FeatureHandler(common.JSONHandler):
       memcache.set(self.MEMCACHE_KEY, properties, time=CACHE_AGE)
 
     properties = self._clean_data(properties)
-    super(FeatureHandler, self).get(properties)
+    # Metrics json shouldn't be cached by intermediary caches because users
+    # see different data when logged in. Set Cache-Control: private.
+    super(FeatureHandler, self).get(properties, public=False)
 
 
 class CSSPopularityHandler(FeatureHandler):

settings.py

@@ -30,3 +30,5 @@ MEMCACHE_KEY_PREFIX = APP_VERSION # For memcache busting on new version
 RSS_FEED_LIMIT = 15
 
 VULCANIZE = True #PROD
+
+DEFAULT_CACHE_TIME = 600 # seconds

static/elements/chromedash-featurelist.html

@@ -165,10 +165,15 @@
         this.fire('filtered', {count: this.filtered.length});
       },
 
-      filter: function(val) {
+      filter: function(val, opt_debounce) {
+        var debounce = opt_debounce || false;
+        if (debounce) {
           this.debounce('filtering', function() {
             this._filterList(val);
           }, 200);
+        } else {
+          this._filterList(val);
+        }
       },
 
       // Returns the index of the first feature of a given milestone string.
@@ -238,7 +243,9 @@
       _deepLinkToFeature: function() {
         this._set_firstLoad(false);
 
-        this.$.ironlist._update(); // force update to list.
+        // TODO(ericbidelman): Originally introduced to fix a bug in ironlist.
+        // Looks fixed now and removing this call helps page load perf!
+        //this.$.ironlist._update(); // force update to list.
 
         document.getElementById('content').classList.add('ready'); // unmask app.
         this.fire('unveiled');

templates/features.html

@@ -129,7 +129,7 @@ search.addEventListener('search', function(e) {
 });
 
 search.addEventListener('input', function(e) {
-  featureList.filter(e.target.value);
+  featureList.filter(e.target.value, true);
   chromeMetadata.selected = null;
 });