Initial commit

utils/github_webhook.py

@@ -0,0 +1,183 @@
+"""
+
+    github-webhook-to-telegram, receive GitHub webhooks and send to Telegram
+    Copyright (C) 2021  Dash Eclipse
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+"""
+import hmac
+import logging
+from hashlib import sha256
+from json.decoder import JSONDecodeError
+from typing import Optional
+
+from aiohttp.web_request import Request
+from multidict import CIMultiDictProxy
+
+from config import GH_WEBHOOKS
+
+
+async def validate_github_webhook(request: Request) -> bool:
+    try:
+        headers = request.headers
+        if not headers.get('User-Agent').startswith('GitHub-Hookshot'):
+            logging.warning("User agent: not from GitHub")
+            return False
+        if headers.get('Content-Type') != 'application/json':
+            logging.warning("Content type: not json")
+            return False
+        payload = await request.json()
+        repo_name = payload['repository']['full_name']
+        if repo_name not in GH_WEBHOOKS.keys():
+            logging.warning("Repository: not in configuration")
+            return False
+        return await _verify_signature(
+            bytes(GH_WEBHOOKS[repo_name]['secret'], 'UTF-8'),
+            headers.get('X-Hub-Signature-256').split('=')[1],
+            await request.read()
+        )
+    except (JSONDecodeError, AttributeError) as error:
+        logging.warning("Invalid: %s", error)
+        return False
+
+
+async def _verify_signature(secret: bytes, sig: str, msg: bytes) -> bool:
+    mac = hmac.new(secret, msg=msg, digestmod=sha256)
+    valid_signature = hmac.compare_digest(mac.hexdigest(), sig)
+    if not valid_signature:
+        logging.warning("Invalid signature")
+    return valid_signature
+
+
+async def format_github_webhook(request: Request) -> Optional[str]:
+    headers: CIMultiDictProxy[str] = request.headers
+    event: str = headers.get('X-GitHub-Event')
+    payload: dict = await request.json()
+    if event in ALL_EVENTS:
+        title = await _get_event_title(event, payload)
+        details = await globals()[f"_format_{event}"](payload)
+        return f"{title}\n{details}" if details else title
+    return None
+
+
+async def _format_create(payload: dict) -> str:
+    return "\u2192 <a href=\"{url}\">{ref_type}: {ref}</a>".format(
+        url=f"{payload['repository']['html_url']}/tree/{payload['ref']}",
+        ref_type=payload['ref_type'],
+        ref=payload['ref']
+    )
+
+
+async def _format_delete(payload: dict) -> str:
+    return "\u2192 {ref_type}: <code>{ref}</code>".format(
+        ref_type=payload['ref_type'],
+        ref=payload['ref']
+    )
+
+
+async def _format_discussion(payload: dict) -> str:
+    discussion = payload['discussion']
+    url = discussion['html_url']
+    title = f"{discussion['title']} \u00b7 Discussion #{discussion['number']}"
+    return f"\u2192 <a href=\"{url}\">{title}</a>"
+
+
+async def _format_fork(payload: dict) -> str:
+    forkee = payload['forkee']
+    return "\u2192 <a href=\"{url}\">{name}</a>".format(
+        url=forkee['html_url'],
+        name=forkee['full_name']
+    )
+
+
+async def _format_issues(payload: dict) -> str:
+    issue = payload['issue']
+    return "\u2192 <a href=\"{url}\">{title}</a>".format(
+        url=issue['html_url'],
+        title=f"{issue['title']} \u00b7 Issue #{issue['number']}"
+    )
+
+
+async def _format_ping(payload: dict) -> str:
+    repository = payload['repository']
+    return "\u2192 <a href=\"{url}\">{name}</a>".format(
+        url=repository['html_url'],
+        name=repository['full_name']
+    )
+
+
+async def _format_public(payload: dict) -> str:
+    repo = payload['repository']
+    return "\u2192 <a href=\"{url}\">{name}</a>".format(
+        url=repo['html_url'],
+        name=repo['full_name']
+    )
+
+
+async def _format_pull_request(payload: dict) -> str:
+    pr = payload['pull_request']
+    url = pr['html_url']
+    user = pr['user']['login']
+    title = f"{pr['title']} by {user} \u00b7 Pull Request #{payload['number']}"
+    return f"\u2192 <a href=\"{url}\">{title}</a>"
+
+
+async def _format_push(payload: dict) -> str:
+    ref = [f"\u2192 {payload['ref']}"]
+    commits = payload['commits']
+    commits_list = [
+        "\u2192 "
+        "<code>{name}</code> {message} [<a href=\"{url}\">{cid}</a>]".format(
+            name=commit['author']['username'],
+            message=commit['message'],
+            url=commit['url'],
+            cid=commit['id'][:7]
+        )
+        for commit in commits
+    ]
+    return "\n".join(ref + commits_list)
+
+
+async def _format_star(payload: dict) -> str:
+    time = payload['starred_at']
+    text = [f"\u2192 starred at <code>{time}</code>"] if time else []
+    text.append(await _get_repo_watch_star_fork(payload['repository']))
+    return "\n".join(text)
+
+
+async def _format_watch(payload: dict) -> str:
+    return await _get_repo_watch_star_fork(payload['repository'])
+
+
+async def _get_event_title(event: str, payload: dict) -> str:
+    sender = payload['sender']['login']
+    action = payload.get('action') or ''
+    return "<b>{name}</b> | <i>{summary}</i>".format(
+        name=payload['repository']['full_name'],
+        summary=" ".join([sender, action, event])
+    )
+
+
+async def _get_repo_watch_star_fork(repo: dict) -> str:
+    return '\u2192 ' + ", ".join([
+        f"<b>{repo['watchers_count']}</b> watchers",
+        f"<b>{repo['stargazers_count']}</b> stargazers",
+        f"<b>{repo['forks_count']}</b> forks"
+    ])
+
+
+ALL_EVENTS = tuple(
+    i.removeprefix('_format_') for i in dir() if i.startswith('_format_')
+)