Return a 400 error when request object could not be created

src/microdot.py

@@ -310,7 +310,6 @@ class Request():
     @staticmethod
     def _safe_readline(stream):
         line = stream.readline(Request.max_readline + 1)
-        print(line, Request.max_readline)
         if len(line) > Request.max_readline:
             raise ValueError('line too long')
         return line
@@ -795,7 +794,11 @@ class Microdot():
         else:
             stream = sock
 
+        req = None
+        try:
             req = Request.create(self, stream, addr)
+        except Exception as exc:  # pragma: no cover
+            print_exception(exc)
         if req:
             if req.content_length > req.max_content_length:
                 if 413 in self.error_handlers:
@@ -836,6 +839,8 @@ class Microdot():
                             res = self.error_handlers[500](req)
                         else:
                             res = 'Internal server error', 500
+        else:
+            res = 'Bad request', 400
         if isinstance(res, tuple):
             res = Response(*res)
         elif not isinstance(res, Response):

src/microdot_asyncio.py

@@ -218,8 +218,12 @@ class Microdot(BaseMicrodot):
         self.server.close()
 
     async def dispatch_request(self, reader, writer):
+        req = None
+        try:
             req = await Request.create(self, reader,
                                        writer.get_extra_info('peername'))
+        except Exception as exc:  # pragma: no cover
+            print_exception(exc)
         if req:
             if req.content_length > req.max_content_length:
                 if 413 in self.error_handlers:
@@ -266,6 +270,8 @@ class Microdot(BaseMicrodot):
                                 self.error_handlers[500], req)
                         else:
                             res = 'Internal server error', 500
+        else:
+            res = 'Bad request', 400
         if isinstance(res, tuple):
             res = Response(*res)
         elif not isinstance(res, Response):

tests/microdot/test_microdot.py

@@ -73,7 +73,10 @@ class TestMicrodot(unittest.TestCase):
         mock_socket._requests.append(fd)
         self._add_shutdown(app)
         app.run()
-        assert fd.response == b''
+        self.assertTrue(fd.response.startswith(b'HTTP/1.0 400 N/A\r\n'))
+        self.assertIn(b'Content-Length: 11\r\n', fd.response)
+        self.assertIn(b'Content-Type: text/plain\r\n', fd.response)
+        self.assertTrue(fd.response.endswith(b'\r\n\r\nBad request'))
 
     def test_method_decorators(self):
         app = Microdot()

tests/microdot_asyncio/test_microdot_asyncio.py

@@ -84,7 +84,10 @@ class TestMicrodotAsync(unittest.TestCase):
         mock_socket._requests.append(fd)
         self._add_shutdown(app)
         app.run()
-        assert fd.response == b''
+        self.assertTrue(fd.response.startswith(b'HTTP/1.0 400 N/A\r\n'))
+        self.assertIn(b'Content-Length: 11\r\n', fd.response)
+        self.assertIn(b'Content-Type: text/plain\r\n', fd.response)
+        self.assertTrue(fd.response.endswith(b'\r\n\r\nBad request'))
 
     def test_before_after_request(self):
         app = Microdot()