为什么我的Python单元测试线程挂起测试用例？

Question

我有以下测试用例。请注意，下面的测试用例不是 试图测试任何东西，只是试图展示我遇到的挂起问题 。

import http.server 
import urllib.request 
import threading 
import unittest 

class FooTest(unittest.TestCase): 
    def setUp(self): 
     print('---- setup start') 
     self.httpd = http.server.HTTPServer(('', 8080), http.server.SimpleHTTPRequestHandler) 
     thread = threading.Thread(target=self.httpd.serve_forever) 
     thread.start() 
     print('---- setup complete') 

    def tearDown(self): 
     print('---- teardown start') 
     self.httpd.shutdown() 
     print('---- teardown complete') 

    def test1(self): 
     print('---- test1 start') 
     print(threading.current_thread()) 
     urllib.request.urlopen('http://127.0.0.1:8080/foo') 
     print('---- test1 complete') 

    def test2(self): 
     print('---- test2 start') 
     print(threading.current_thread()) 
     urllib.request.urlopen('http://127.0.0.1:8080/foo') 
     print('---- test2 complete') 

if __name__ == '__main__': 
    unittest.main() 

我希望在尝试执行这个测试用例时发生2个错误。相反， 测试用例会在以下输出之后挂起。

C:\lab>python foo.py -v 
test1 (__main__.FooTest) ... ---- setup start 
---- setup complete 
---- test1 start 
<_MainThread(MainThread, started 12980)> 
127.0.0.1 - - [24/Mar/2014 21:53:57] code 404, message File not found 
127.0.0.1 - - [24/Mar/2014 21:53:57] "GET /foo HTTP/1.1" 404 - 
---- teardown start 
---- teardown complete 
ERROR 
test2 (__main__.FooTest) ... ---- setup start 
---- setup complete 
---- test2 start 
<_MainThread(MainThread, started 12980)> 

如果我从代码中删除test2，那么我期待只有1个错误，并确保足够 我看到它。

C:\lab>python foo.py -v 
test1 (__main__.FooTest) ... ---- setup start 
---- setup complete 
---- test1 start 
<_MainThread(MainThread, started 15720)> 
127.0.0.1 - - [24/Mar/2014 21:55:12] code 404, message File not found 
127.0.0.1 - - [24/Mar/2014 21:55:12] "GET /foo HTTP/1.1" 404 - 
---- teardown start 
---- teardown complete 
ERROR 

====================================================================== 
ERROR: test1 (__main__.FooTest) 
---------------------------------------------------------------------- 
Traceback (most recent call last): 
    File "foo.py", line 22, in test1 
    urllib.request.urlopen('http://127.0.0.1:8080/foo') 
    File "C:\Python34\lib\urllib\request.py", line 153, in urlopen 
    return opener.open(url, data, timeout) 
    File "C:\Python34\lib\urllib\request.py", line 461, in open 
    response = meth(req, response) 
    File "C:\Python34\lib\urllib\request.py", line 574, in http_response 
    'http', request, response, code, msg, hdrs) 
    File "C:\Python34\lib\urllib\request.py", line 499, in error 
    return self._call_chain(*args) 
    File "C:\Python34\lib\urllib\request.py", line 433, in _call_chain 
    result = func(*args) 
    File "C:\Python34\lib\urllib\request.py", line 582, in http_error_default 
    raise HTTPError(req.full_url, code, msg, hdrs, fp) 
urllib.error.HTTPError: HTTP Error 404: File not found 

---------------------------------------------------------------------- 
Ran 1 test in 0.032s 

FAILED (errors=1) 

为什么测试用例会挂起，如果有2个测试出错？

Answer 1

通话添加到server_close关闭套接字：

def setUp(self): 
    print('---- setup start') 
    handler = http.server.SimpleHTTPRequestHandler 
    self.httpd = http.server.HTTPServer(('', 8080), handler) 
    threading.Thread(target=self.serve).start() 
    print('---- setup complete') 

def serve(self): 
    try: 
     self.httpd.serve_forever() 
    finally: 
     self.httpd.server_close() 

Answer 2

我找到了另一种方式来在测试用例运行的httpd

import unittest 
import threading 
from http.server import HTTPServer, BaseHTTPRequestHandler 

class TestHttpRequests(unittest.TestCase): 
    @classmethod 
    def setUpClass(cls): 
     cls.httpd = HTTPServer(handler=BaseHTTPRequestHandler) 
     threading.Thread(target=cls.httpd.serve_forever).start() 

    @classmethod 
    def tearDownClass(cls): 
     cls.httpd.shutdown()