import socketserver
import urllib.request, urllib.error
import threading
import time
import unittest

HOST = "localhost"
SLEEPTIME = 0.1

class MyTCPHandler(socketserver.BaseRequestHandler):
    def handle(self):
        self.request.recv(1024)
        time.sleep(SLEEPTIME)
        self.request.send(b"HTTP/1.0 Foo \n")
        self.request.close()


class test_urllibi_except(unittest.TestCase):
    def test_timeout(self):
        with self.assertRaises(urllib.error.URLError):
            self._fetch_url("http://%s:%d/"%(HOST,PORT),                                             timeout=SLEEPTIME/10)
            
    def test_badhost(self):
        with self.assertRaises(urllib.error.URLError):
            self._fetch_url("http://example.example/")

    def test_httperror(self):
        with self.assertRaises(urllib.error.URLError):
            self._fetch_url("http://%s:%d/"%(HOST,PORT))

    @staticmethod
    def _fetch_url(url,timeout=SLEEPTIME*10):
        conn = urllib.request.urlopen(url,timeout=timeout)
        try:
            conn.read()
        finally:
            if conn:
                conn.close()


if __name__=="__main__":
    server = socketserver.TCPServer((HOST, 0), MyTCPHandler)
    global PORT
    PORT = server.server_address[1]
    server_thread = threading.Thread(target=server.serve_forever)
    server_thread.daemon = True
    server_thread.start()
    unittest.main()
    server.shutdown()