How to Build a Mock Route53 DNS API in Python

import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs


class DNSUpdateHandler(BaseHTTPRequestHandler):
    records = {"example.com": "1.2.3.4"}

    def do_GET(self):
        domain = parse_qs(urlparse(self.path).query).get("domain", [""])[0]
        if domain in self.records:
            self._send(200, {"domain": domain, "ip": self.records[domain]})
        else:
            self._send(404, {"error": "Record not found"})

    def do_PUT(self):
        content_length = int(self.headers.get("Content-Length", 0))
        body = json.loads(self.rfile.read(content_length) or b"{}")
        domain = body.get("domain")
        ip = body.get("ip")
        if not domain or not ip:
            self._send(400, {"error": "domain and ip required"})
            return
        self.records[domain] = ip
        self._send(200, {"domain": domain, "ip": ip, "status": "updated"})

    def _send(self, status, payload):
        self.send_response(status)
        self.send_header("Content-Type", "application/json")
        self.end_headers()
        self.wfile.write(json.dumps(payload).encode())

    def log_message(self, format, *args):
        pass


if __name__ == "__main__":
    server = HTTPServer(("localhost", 8080), DNSUpdateHandler)
    print("Mock Route53 DNS API running on port 8080")
    server.serve_forever()