Add Cache-Control headers.

API_CHANGELOG.rst

@@ -12,9 +12,10 @@ API Changelog
 - archive-date and archive-date-l10n return a missing status for
   anything else than nightly versions.
 - Add the devedition-beta-versions-matches endpoint and task.
+- Add Cache-Control headers.
 
 
 1.0 (2017-08-08)
 ----------------
 
-- First version of PollBot
+- First version of PollBot.

CHANGELOG.rst

@@ -13,6 +13,7 @@ CHANGELOG
 - Fix the ESR download links task url (#66)
 - Add a task to validate if devedition and beta version matches (#78)
 - Redirects URL ending by a / to URL without the / in case of 404. (#54)
+- Add Cache-Control headers (#43)
 
 
 0.1.0 (2017-08-08)

pollbot/middlewares.py

@@ -1,5 +1,6 @@
 import logging
 from aiohttp import web
+import os
 
 logger = logging.getLogger(__package__)
 
@@ -8,8 +9,26 @@ def setup_middlewares(app):
     error_middleware = error_pages({404: handle_404,
                                     500: handle_500})
     app.middlewares.append(error_middleware)
+    app.middlewares.append(cache_control_middleware)
 
 
+# Cache-Control middleware
+CACHE_MAX_AGE = int(os.getenv("CACHE_MAX_AGE", "30"))
+NO_CACHE_ENDPOINTS = ['/v1/', '/v1/__version__', '/v1/__heartbeat__', '/v1/__lbheartbeat__']
+
+
+async def cache_control_middleware(app, handler):
+    async def middleware_handler(request):
+        response = await handler(request)
+        cache_control_value = "public; max-age={}".format(CACHE_MAX_AGE)
+        if request.path in NO_CACHE_ENDPOINTS or CACHE_MAX_AGE <= 0:
+            cache_control_value = "no-cache"
+        response.headers.setdefault("Cache-Control", cache_control_value)
+        return response
+    return middleware_handler
+
+
+# Error page middlewares
 def error_pages(overrides):
     async def middleware(app, handler):
         async def middleware_handler(request):

tests/test_views.py

@@ -8,6 +8,7 @@ from aiohttp import web
 
 from pollbot import __version__ as pollbot_version, HTTP_API_VERSION
 from pollbot.app import get_app
+from pollbot.middlewares import NO_CACHE_ENDPOINTS
 from pollbot.exceptions import TaskError
 from pollbot.views.release import status_response
 from pollbot.utils import Status
@@ -380,3 +381,23 @@ async def test_ongoing_versions_view(cli):
     assert "release" in body
     assert "beta" in body
     assert "nightly" in body
+
+
+@pytest.mark.parametrize("endpoint", NO_CACHE_ENDPOINTS)
+async def test_endpoint_have_got_cache_control_headers(cli, endpoint):
+    resp = await cli.get(endpoint)
+    assert "Cache-Control" in resp.headers
+    assert resp.headers["Cache-Control"] == "no-cache"
+
+
+async def test_product_endpoint_have_got_cache_control_headers(cli):
+    resp = await cli.get("/v1/firefox/54.0")
+    assert "Cache-Control" in resp.headers
+    assert resp.headers["Cache-Control"] == "public; max-age=30"
+
+
+async def test_cache_control_header_max_age_can_be_parametrized(cli):
+    with mock.patch("pollbot.middlewares.CACHE_MAX_AGE", 10):
+        resp = await cli.get("/v1/firefox/54.0")
+        assert "Cache-Control" in resp.headers
+        assert resp.headers["Cache-Control"] == "public; max-age=10"