Add Cloudflare utilities

cloudflare/tests/test_cache_tag_purge.py

@@ -0,0 +1,52 @@
+from unittest.mock import patch
+
+from django.test import TestCase, override_settings
+
+from cloudflare.utils import purge_tags_from_cache, purge_all_from_cache
+
+
+@override_settings(WAGTAILFRONTENDCACHE={
+    'cloudflare': {
+        'BACKEND': 'wagtail.contrib.wagtailfrontendcache.backends.CloudflareBackend',
+        'EMAIL': 'CLOUDFLARE_FAKE_EMAIL',
+        'TOKEN': 'CLOUDFLARE_FAKE_TOKEN',
+        'ZONEID': 'CLOUDFLARE_FAKE_ZONE',
+    }
+})
+class TestCacheTags(TestCase):
+
+    @patch('cloudflare.utils.requests.delete')
+    def test_cache_tag_purge(self, requests_delete):
+        """
+        Should fire an appropriate looking HTTP request to Cloudflare's
+        purge API endpoint
+        """
+        purge_tags_from_cache(['tag-1', 'tag-2'])
+        requests_delete.assert_called_with(
+            'https://api.cloudflare.com/client/v4/zones/CLOUDFLARE_FAKE_ZONE/purge_cache',
+            json={
+                'tags': ['tag-1', 'tag-2']
+            },
+            headers={
+                'X-Auth-Email': 'CLOUDFLARE_FAKE_EMAIL',
+                'Content-Type': 'application/json',
+                'X-Auth-Key': 'CLOUDFLARE_FAKE_TOKEN'
+            }
+        )
+
+    @patch('cloudflare.utils.requests.delete')
+    def test_cache_purge_all(self, requests_delete):
+        """
+        Should fire an appropriate looking HTTP request to Cloudflare's
+        purge API endpoint
+        """
+        purge_all_from_cache()
+        requests_delete.assert_called_with(
+            'https://api.cloudflare.com/client/v4/zones/CLOUDFLARE_FAKE_ZONE/purge_cache',
+            json={},
+            headers={
+                'X-Auth-Email': 'CLOUDFLARE_FAKE_EMAIL',
+                'Content-Type': 'application/json',
+                'X-Auth-Key': 'CLOUDFLARE_FAKE_TOKEN'
+            }
+        )

cloudflare/utils.py

@@ -0,0 +1,72 @@
+import logging
+import requests
+import json
+
+from typing import Iterable
+
+from wagtail.contrib.wagtailfrontendcache.utils import get_backends
+from wagtail.contrib.wagtailfrontendcache.backends import CloudflareBackend
+
+
+logger = logging.getLogger('wagtail.frontendcache')
+
+
+def _for_every_cloudflare_backend(func: callable) -> callable:
+    "Decorator to run a function once for every Cloudflare backend"
+
+    def inner(*args, backend_settings=None, backends=None, **kwargs):
+        for backend_name, backend in get_backends(backend_settings=backend_settings, backends=backends).items():
+            if not isinstance(backend, CloudflareBackend):
+                continue
+            func(*args, backend=backend, **kwargs)
+
+    return inner
+
+
+def _purge(backend: CloudflareBackend, data={}) -> None:
+    "Send a delete request to the Cloudflare API"
+    purge_url = 'https://api.cloudflare.com/client/v4/zones/{0}/purge_cache'.format(backend.cloudflare_zoneid)
+    string_data = json.dumps(data)
+
+    response = requests.delete(
+        purge_url,
+        json=data,
+        headers={
+            "X-Auth-Email": backend.cloudflare_email,
+            "X-Auth-Key": backend.cloudflare_token,
+            "Content-Type": "application/json",
+        },
+    )
+
+    try:
+        response_json = response.json()
+    except ValueError:
+        if response.status_code != 200:
+            response.raise_for_status()
+        else:
+            logger.error("Couldn't purge from Cloudflare with data: %s. Unexpected JSON parse error.", string_data)
+
+    except requests.exceptions.HTTPError as e:
+        logger.error("Couldn't purge from Cloudflare with data: %s. HTTPError: %d %s", string_data, e.response.status_code, e.message)
+        return
+
+    except requests.exceptions.InvalidURL as e:
+        logger.error("Couldn't purge from Cloudflare with data: %s. URLError: %s", string_data, e.message)
+        return
+
+    if response_json['success'] is False:
+        error_messages = ', '.join([str(err['message']) for err in response_json['errors']])
+        logger.error("Couldn't purge from Cloudflare with data: %s. Cloudflare errors '%s'", string_data, error_messages)
+        return
+
+
+@_for_every_cloudflare_backend
+def purge_tags_from_cache(tags: Iterable, backend: CloudflareBackend) -> None:
+    "Purge tags by list. Requires an enterprise Cloudflare subscription"
+    _purge(backend=backend, data={"tags": tags})
+
+
+@_for_every_cloudflare_backend
+def purge_all_from_cache(backend: CloudflareBackend) -> None:
+    "Purge an entire zone"
+    _purge(backend=backend)

securedrop/settings/base.py

@@ -32,6 +32,7 @@
     'accounts',
     'autocomplete',
     'blog',
+    'cloudflare',
     'common',
     'home',
     'marketing',