Add whitelist health check

src/app.py

@@ -2,9 +2,14 @@
 import os
 
 from flask import Flask, jsonify
+import requests
 
 app = Flask(__name__)
 VERSION = "0.1.0"
+WHITELIST_URL = os.getenv(
+    "WHITELIST_URL",
+    "https://whitelist.nodejsk8s.services.ngcloud.ru/v2/app",
+)
 
 
 def mariadb_configuration():
@@ -18,6 +23,27 @@ def mariadb_configuration():
     }
 
 
+def check_whitelist():
+    headers = {}
+    token = os.getenv("WHITELIST_TOKEN")
+    if token:
+        headers["Authorization"] = f"Bearer {token}"
+    response = requests.get(
+        WHITELIST_URL,
+        headers=headers,
+        allow_redirects=False,
+        timeout=int(os.getenv("WHITELIST_TIMEOUT", "10")),
+    )
+    content_type = response.headers.get("Content-Type", "")
+    body = response.json() if "json" in content_type else response.text
+    return {
+        "url": WHITELIST_URL,
+        "status": response.status_code,
+        "location": response.headers.get("Location"),
+        "body": body,
+    }
+
+
 @app.get("/")
 def index():
     return jsonify({
@@ -34,6 +60,15 @@ def health():
     return jsonify({"ok": True, "version": VERSION})
 
 
+@app.get("/check")
+def check():
+    try:
+        result = check_whitelist()
+        return jsonify({"ok": 200 <= result["status"] < 300, **result})
+    except requests.RequestException as exc:
+        return jsonify({"ok": False, "url": WHITELIST_URL, "error": str(exc)}), 502
+
+
 @app.get("/mariadb")
 def mariadb():
     return jsonify(mariadb_configuration())

src/requirements.txt

@@ -1 +1,2 @@
-flask
+flask
+requests