database_server.py

#!/usr/bin/env python3
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs

DB = {}

class KeyValueHandler(BaseHTTPRequestHandler):
    def send_404(self, message=b'ERROR: Unknown endpoint\n'):
        self.send_response(404)
        self.send_header('Content-type', 'text/plain')
        self.end_headers()
        self.wfile.write(message)
    
    def do_POST(self):
        parsed_path = urlparse(self.path)
        path = parsed_path.path
        query_params = parse_qs(parsed_path.query)
        
        if path != '/set':
            self.send_404()
            return
        
        for key, value_list in query_params.items():
            DB[key] = value_list[0]
        
        self.send_response(200)
        self.send_header('Content-type', 'text/plain')
        self.end_headers()
        self.wfile.write(b'OK: Key-value pairs stored\n')
    
    def do_GET(self):
        parsed_path = urlparse(self.path)
        path = parsed_path.path
        query_params = parse_qs(parsed_path.query)
        
        if path != '/get':
            self.send_404()
            return
        
        key = query_params.get('key', [None])[0]
        
        if key is None:
            self.send_response(400)
            self.send_header('Content-type', 'text/plain')
            self.end_headers()
            self.wfile.write(b'ERROR: No key parameter provided\n')
        elif key in DB:
            self.send_response(200)
            self.send_header('Content-type', 'text/plain')
            self.end_headers()
            self.wfile.write(DB[key].encode('utf-8') + b'\n')
        else:
            self.send_404(b'ERROR: Key not found\n')
    
    def log_message(self, format, *args):
        print(f"[{self.log_date_time_string()}] {format % args}")

def run_server(port=4000):
    server_address = ('', port)
    httpd = HTTPServer(server_address, KeyValueHandler)
    print(f'Server running on http://localhost:{port}/')
    print(f'Use POST /set?key=value to store data')
    print(f'Use GET /get?key=key to retrieve data')
    print('Press Ctrl+C to stop the server')
    try:
        httpd.serve_forever()
    except KeyboardInterrupt:
        print('\nServer stopped.')
        httpd.server_close()

if __name__ == '__main__':
    run_server()