Add VK callback auth support and admin demotion

deploy/vk_callback_server.py

@@ -0,0 +1,78 @@
+import argparse
+import os
+from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
+from pathlib import Path
+
+
+DEFAULT_HOST = "127.0.0.1"
+DEFAULT_PORT = 8787
+CALLBACK_PATH = "/vk/callback"
+HEALTH_PATH = "/health"
+
+
+def _read_callback_html():
+    html_path = Path(__file__).resolve().parent / "vk-callback" / "index.html"
+    return html_path.read_bytes()
+
+
+class VkCallbackHandler(BaseHTTPRequestHandler):
+    server_version = "AnabasisVkCallback/1.0"
+
+    def do_GET(self):
+        path = self.path.split("?", 1)[0]
+        if path == HEALTH_PATH:
+            self._send_text(200, "ok\n")
+            return
+        if path in ("/", CALLBACK_PATH):
+            self._send_html(200, _read_callback_html())
+            return
+        self._send_text(404, "not found\n")
+
+    def log_message(self, fmt, *args):
+        if getattr(self.server, "quiet", False):
+            return
+        super().log_message(fmt, *args)
+
+    def _send_html(self, status, body):
+        self.send_response(status)
+        self.send_header("Content-Type", "text/html; charset=utf-8")
+        self.send_header("Cache-Control", "no-store")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+    def _send_text(self, status, text):
+        body = text.encode("utf-8")
+        self.send_response(status)
+        self.send_header("Content-Type", "text/plain; charset=utf-8")
+        self.send_header("Cache-Control", "no-store")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+
+def parse_args():
+    parser = argparse.ArgumentParser(description="Anabasis VK OAuth callback host")
+    parser.add_argument("--host", default=os.getenv("ANABASIS_VK_CALLBACK_HOST", DEFAULT_HOST))
+    parser.add_argument("--port", type=int, default=int(os.getenv("ANABASIS_VK_CALLBACK_PORT", DEFAULT_PORT)))
+    parser.add_argument("--quiet", action="store_true")
+    return parser.parse_args()
+
+
+def main():
+    args = parse_args()
+    server = ThreadingHTTPServer((args.host, args.port), VkCallbackHandler)
+    server.quiet = args.quiet
+    print(f"VK callback server listening on http://{args.host}:{args.port}{CALLBACK_PATH}")
+    print(f"Health check: http://{args.host}:{args.port}{HEALTH_PATH}")
+    try:
+        server.serve_forever()
+    except KeyboardInterrupt:
+        pass
+    finally:
+        server.server_close()
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())