Implement the github-filter worker in the API

The current github-filter worker, found at
https://github.com/python-discord/workers/blob/main/github-filter/src/index.ts,
fails to work at present because Discord's webhook endpoints block
Cloudflare's IP ranges from accessing this endpoint. Whilst they use
Cloudflare to guard themselves, it seems they do not wish others to use
it.

Implement it on the site to circumvent IP restrictions and allow to
modify the code in Python.

1 files changed, 46 insertions, 0 deletions

diff --git a/pydis_site/apps/api/tests/test_github_webhook_filter.py b/pydis_site/apps/api/tests/test_github_webhook_filter.py
new file mode 100644
index 00000000..2c9f59e5
--- /dev/null
+++ b/pydis_site/apps/api/tests/test_github_webhook_filter.py
@@ -0,0 +1,46 @@
+from unittest import mock
+
+from django.urls import reverse
+from rest_framework.test import APITestCase
+
+
+class GitHubWebhookFilterAPITests(APITestCase):
+    def test_ignores_bot_sender(self):
+        url = reverse('api:github-webhook-filter', args=('id', 'token'))
+        payload = {'sender': {'login': 'limette', 'type': 'bot'}}
+        headers = {'X-GitHub-Event': 'pull_request_review'}
+        response = self.client.post(url, data=payload, headers=headers)
+        self.assertEqual(response.status_code, 203)
+
+    def test_accepts_interesting_events(self):
+        url = reverse('api:github-webhook-filter', args=('id', 'token'))
+        payload = {
+            'ref': 'refs/heads/master',
+            'pull_request': {
+                'user': {
+                    'login': "lemon",
+                }
+            },
+            'review': {
+                'state': 'commented',
+                'body': "Amazing!!!"
+            },
+            'repository': {
+                'name': 'black',
+                'owner': {
+                    'login': 'psf',
+                }
+            }
+        }
+        headers = {'X-GitHub-Event': 'pull_request_review'}
+
+        with mock.patch('urllib.request.urlopen') as urlopen:
+            urlopen.return_value = mock.MagicMock()
+            context_mock = urlopen.return_value.__enter__.return_value
+            context_mock.status = 299
+            context_mock.getheaders.return_value = [('X-Clacks-Overhead', 'Joe Armstrong')]
+            context_mock.read.return_value = b'{"status": "ok"}'
+
+            response = self.client.post(url, data=payload, headers=headers)
+            self.assertEqual(response.status_code, context_mock.status)
+            self.assertEqual(response.headers.get('X-Clacks-Overhead'), 'Joe Armstrong')