URL shortener

server.py

from http.server import BaseHTTPRequestHandler
from http.server import ThreadingHTTPServer
from typing import Dict
from uuid import uuid4
import json

database: Dict[str, str] = dict()

class HttpGetHandler(BaseHTTPRequestHandler):
    def _set_headers(self, status: int = 200, c_type: str = "text/html"):
        self.send_response(status)
        self.send_header("Content-type", c_type)
        self.end_headers()

    def _json(self, status: int, message: Dict[str, str]):
        self._set_headers(status, "application/json")
        return json.dumps(message).encode("utf8")

    def do_GET(self):
        if self.path == "/":
            message = {"message": "Welcome to the main page"}
            self.wfile.write(self._json(200, message))
        elif self.path in database:
            self.send_response(301)
            self.send_header('Location', database[self.path])
            self.end_headers()
        else:
            message = {"error": "No such url in db"}
            self.wfile.write(self._json(404, message))

    def do_POST(self):
        content_length = int(self.headers['Content-Length'])
        post_data = json.loads(self.rfile.read(content_length).decode("utf-8"))
        if "long" in post_data:
            short = "/" + str(uuid4())
            database.update({short: post_data["long"]})
            message = {"short": f"http://localhost:8000/{short[1:]}"}
            self.wfile.write(self._json(200, message))
        else:
            message = {"error": "Your data is wrong"}
            self.wfile.write(self._json(404, message))

def run(server_class = ThreadingHTTPServer, handler_class = HttpGetHandler):
    server_address = ('', 8000)
    httpd = server_class(server_address, handler_class)
    try:
        httpd.serve_forever()
    except KeyboardInterrupt:
        httpd.server_close()

if __name__ == "__main__":
    run()