Merge pull request #89 from mozilla/85-cdn-headers

Adds cache TTLs:

recommendation/conf.py

@@ -4,6 +4,9 @@
 DEBUG = env.get('RECOMMENDATION_ENV', 'development') == 'development'
 KEY_PREFIX = env.get('RECOMMENDATION_KEY_PREFIX', 'query_')
 
+CACHE_TTL = env.get('RECOMMENDATION_CACHE_TTL', 7 * 24 * 60 * 60)
+MEMCACHED_TTL = env.get('RECOMMENDATION_MEMCACHED_TTL', CACHE_TTL)
+
 BING_ACCOUNT_KEY = env.get('BING_ACCOUNT_KEY', '')
 EMBEDLY_API_KEY = env.get('EMBEDLY_API_KEY', '')
 YAHOO_OAUTH_KEY = env.get('YAHOO_OAUTH_KEY', '')

recommendation/memorize.py

@@ -5,6 +5,7 @@
 
 from wrapt import ObjectProxy
 
+from recommendation.conf import MEMCACHED_TTL
 from recommendation.memcached import memcached
 
 
@@ -85,7 +86,7 @@ def attr(self, key):
     author.from_cache            # False
     author.cache_key             # 'memorize_cd2db0e4dc383ea0c5643ce6478612a3'
     """
-    def __init__(self, prefix='memorized', ttl=0):
+    def __init__(self, prefix='memorized', ttl=MEMCACHED_TTL):
         self.prefix = prefix
         self.ttl = ttl
 

recommendation/tasks/task_recommend.py

@@ -1,3 +1,4 @@
+from recommendation.conf import MEMCACHED_TTL
 from recommendation.factory import create_queue
 from recommendation.memcached import memcached
 from recommendation.search.recommendation import SearchRecommendation
@@ -9,5 +10,5 @@
 @queue.task(name='main.recommend')
 def recommend(q, key):
     recommendation = SearchRecommendation(q).do_search(q)
-    memcached.set(key, recommendation)
+    memcached.set(key, recommendation, time=MEMCACHED_TTL)
     return recommendation

recommendation/views/main.py

@@ -1,6 +1,7 @@
 import hashlib
 
-from flask import abort, current_app, Blueprint, jsonify, request
+from flask import (abort, after_this_request, current_app, Blueprint, jsonify,
+                   request)
 
 from recommendation import conf
 from recommendation.memcached import memcached
@@ -11,6 +12,15 @@
 
 @main.route('/')
 def view():
+
+    @after_this_request
+    def cache_control_headers(response):
+        if response.status_code == 200:
+            response.headers['Cache-Control'] = 'max-age=%d' % conf.CACHE_TTL
+        else:
+            response.headers['Cache-Control'] = 'no-cache, must-revalidate'
+        return response
+
     from recommendation.tasks.task_recommend import recommend
     query = request.args.get('q')
     if not query:
@@ -19,6 +29,7 @@ def view():
         conf.KEY_PREFIX,
         hashlib.md5(str(query).encode('utf-8')).hexdigest()
     ])
+
     try:
         response = memcached.get(key)
     except Exception as e:

recommendation/views/tests/test_main.py

@@ -3,6 +3,7 @@
 from mock import patch
 from nose.tools import eq_, ok_
 
+from recommendation.conf import CACHE_TTL
 from recommendation.cors import cors_headers
 from recommendation.tests.memcached import mock_memcached
 from recommendation.tests.util import AppTestCase
@@ -33,6 +34,13 @@ def _query(self, query):
         })
         return self._get(url)
 
+    def _cached(self, response):
+        ok_('max-age=%d' % CACHE_TTL in response.headers['Cache-Control'])
+
+    def _not_cached(self, response):
+        ok_('no-cache' in response.headers['Cache-Control'])
+        ok_('must-revalidate' in response.headers['Cache-Control'])
+
     def test_cors(self):
         headers = [
             'Access-Control-Allow-Headers',
@@ -46,27 +54,34 @@ def test_cors(self):
                  for header in headers]))
 
     def test_no_query(self):
-        eq_(self._get('/').status_code, 400)
+        response = self._get('/')
+        eq_(response.status_code, 400)
+        self._not_cached(response)
 
     @patch('recommendation.tasks.task_recommend.memcached.get')
     def test_exception(self, mock_get):
         mock_get.side_effect = EXCEPTION
         response = self._query(QUERY)
         eq_(response.status_code, 500)
         eq_(response.json, {})
+        self._not_cached(response)
 
     @patch('recommendation.tasks.task_recommend.memcached.get')
     def test_cache_hit(self, mock_get):
         mock_get.return_value = RESULTS
-        eq_(self._query(QUERY).status_code, 200)
-        eq_(self._query(QUERY).json, RESULTS)
+        response = self._query(QUERY)
+        eq_(response.status_code, 200)
+        eq_(response.json, RESULTS)
+        self._cached(response)
 
     @patch('recommendation.tasks.task_recommend.memcached.get')
     @patch('recommendation.tasks.task_recommend.recommend.delay')
     def test_cache_miss(self, mock_delay, mock_get):
         mock_get.return_value = None
-        eq_(self._query(QUERY).status_code, 202)
+        response = self._query(QUERY)
+        eq_(response.status_code, 202)
         eq_(mock_delay.call_count, 1)
+        self._not_cached(response)
 
 
 class TestMainDebug(TestMain):
@@ -79,5 +94,6 @@ def test_exception(self, mock_delay, mock_get):
         response = self._query(QUERY)
         exception_name = list(response.json.keys())[0]
         eq_(response.status_code, 500)
+        self._not_cached(response)
         eq_(exception_name, EXCEPTION.__class__.__name__)
         eq_(response.json[exception_name], EXCEPTION_ARGS)