feat: add healthcheck endpoint (#10)

.dockerignore

@@ -3,5 +3,6 @@
 
 # Allow files and directories
 !/webhook_telegram_bot
+!/healthcheck.py
 !/poetry.lock
 !/pyproject.toml

Dockerfile

@@ -62,6 +62,10 @@ RUN set -ex \
 
 COPY --chown=app:app ./webhook_telegram_bot /app/webhook_telegram_bot
 
+COPY --chown=app:app ./healthcheck.py /app
+
 EXPOSE 8080
 
+HEALTHCHECK --interval=10s --timeout=10s --retries=3 CMD /app/venv/bin/python healthcheck.py || exit 1
+
 CMD [ "/sbin/tini", "--", "/app/venv/bin/python", "-m", "webhook_telegram_bot.main", "--host", "0.0.0.0", "--port", "8080"]

healthcheck.py

@@ -0,0 +1,27 @@
+#!/usr/bin/env python
+"""Custom healthcheck script."""
+import sys
+from urllib.error import HTTPError, URLError
+from urllib.request import urlopen
+
+
+def main() -> None:
+    """
+    Entrypoint.
+
+    :return: None
+    """
+    try:
+        response = urlopen('http://127.0.0.1:8080/api/v1/health')  # nosec
+        if response.code == 200:
+            sys.exit(0)
+        else:
+            sys.exit(1)
+    except HTTPError:
+        sys.exit(1)
+    except URLError:
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    main()

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "webhook-telegram-bot"
-version = "1.0.0"
+version = "1.1.0"
 description = ""
 authors = ["Dmitrii Zakharov <dmitrii@zakharov.cc>"]
 license = "MIT"

tests/test_handlers.py

@@ -0,0 +1,16 @@
+from aiohttp import web
+
+from webhook_telegram_bot.main import init_routes
+
+
+async def test_health_handler(aiohttp_client):
+    app = web.Application()
+    init_routes(app)
+    client = await aiohttp_client(app)
+    url = client.app.router["health"].url_for()
+    result = await client.get(url)
+
+    assert result.status == 200
+
+    data = await result.json()
+    assert data.get("health") == "ok"

webhook_telegram_bot/handlers.py

@@ -0,0 +1,12 @@
+"""This file contains handlers for common purposes."""
+from aiohttp import web
+from aiohttp.web_response import Response
+
+
+async def health_handler(request: web.Request) -> Response:
+    """
+    Return healthcheck response.
+
+    :return: Response
+    """
+    return web.json_response({"health": "ok"})

webhook_telegram_bot/main.py

@@ -13,6 +13,7 @@
     ImproperlyConfiguredException,
     WebhookBotException,
 )
+from webhook_telegram_bot.handlers import health_handler
 from webhook_telegram_bot.helpers import (
     get_config_value,
     get_database,
@@ -175,6 +176,16 @@ async def on_shutdown_telegram_handler(app_: web.Application) -> None:
     init_telegram_routes(app)
 
 
+def init_routes(app: web.Application) -> None:
+    """
+    Initialize common application routes.
+
+    :param app: application instance
+    :return:
+    """
+    app.router.add_route("GET", "/api/v1/health", health_handler, name="health")
+
+
 async def create_app(config: Optional[Dict[str, str]] = None) -> web.Application:
     """
     Create application.
@@ -189,6 +200,7 @@ async def create_app(config: Optional[Dict[str, str]] = None) -> web.Application
     init_plugins(app)
     init_templates(app)
     init_telegram(app)
+    init_routes(app)
     return app