Python urllib3 模块，connection() 实例源码

def get(self, url, timeout=None):
        """Request an URL.

        Args:
            url (str): The web location we want to retrieve.
            timeout (Optional[int|float]): If this value is specified, use it as the read timeout
                from the server (instead of the one specified during creation of the connection
                pool).

        Returns:
          A JSON object.

        """
        urlopen_kwargs = {}

        if timeout is not None:
            urlopen_kwargs['timeout'] = Timeout(read=timeout, connect=self._connect_timeout)

        result = self._request_wrapper('GET', url, **urlopen_kwargs)
        return self._parse(result)

def post(self, url, data, timeout=None):
        """Request an URL.
        Args:
            url (str): The web location we want to retrieve.
            data (dict[str, str]): A dict of key/value pairs. Note: On py2.7 value is unicode.
            timeout (Optional[int|float]): If this value is specified, use it as the read timeout
                from the server (instead of the one specified during creation of the connection
                pool).

        Returns:
          A JSON object.

        """
        urlopen_kwargs = {}

        if timeout is not None:
            urlopen_kwargs['timeout'] = Timeout(read=timeout, connect=self._connect_timeout)

        if InputFile.is_inputfile(data):
            data = InputFile(data)
            result = self._request_wrapper(
                'POST', url, body=data.to_form(), headers=data.headers, **urlopen_kwargs)
        else:
            data = json.dumps(data)
            result = self._request_wrapper(
                'POST',
                url,
                body=data.encode(),
                headers={'Content-Type': 'application/json'},
                **urlopen_kwargs)

        return self._parse(result)

def retrieve(self, url, timeout=None):
        """Retrieve the contents of a file by its URL.

        Args:
            url (str): The web location we want to retrieve.
            timeout (Optional[int|float]): If this value is specified, use it as the read timeout
                from the server (instead of the one specified during creation of the connection
                pool).

        """
        urlopen_kwargs = {}
        if timeout is not None:
            urlopen_kwargs['timeout'] = Timeout(read=timeout, connect=self._connect_timeout)

        return self._request_wrapper('GET', url, **urlopen_kwargs)

def download(self, url, filename, timeout=None):
        """Download a file by its URL.
        Args:
            url (str): The web location we want to retrieve.
            timeout (Optional[int|float]): If this value is specified, use it as the read timeout
                from the server (instead of the one specified during creation of the connection
                pool).

          filename:
            The filename within the path to download the file.

        """
        buf = self.retrieve(url, timeout=timeout)
        with open(filename, 'wb') as fobj:
            fobj.write(buf)

def _request_wrapper(self, *args, **kwargs):
        """Wraps urllib3 request for handling known exceptions.

        Args:
            args: unnamed arguments, passed to urllib3 request.
            kwargs: keyword arguments, passed tp urllib3 request.

        Returns:
            str: A non-parsed JSON text.

        Raises:
            TelegramError

        """
        # Make sure to hint Telegram servers that we reuse connections by sending
        # "Connection: keep-alive" in the HTTP headers.
        if 'headers' not in kwargs:
            kwargs['headers'] = {}
        kwargs['headers']['connection'] = 'keep-alive'

        try:
            resp = self._con_pool.request(*args, **kwargs)
        except urllib3.exceptions.TimeoutError:
            raise TimedOut()
        except urllib3.exceptions.HTTPError as error:
            # HTTPError must come last as its the base urllib3 exception class
            # TODO: do something smart here; for now just raise NetworkError
            raise NetworkError('urllib3 HTTPError {0}'.format(error))

        if 200 <= resp.status <= 299:
            # 200-299 range are HTTP success statuses
            return resp.data

        try:
            message = self._parse(resp.data)
        except ValueError:
            raise NetworkError('Unknown HTTPError {0}'.format(resp.status))

        if resp.status in (401, 403):
            raise Unauthorized(message)
        elif resp.status == 400:
            raise BadRequest(message)
        elif resp.status == 404:
            raise InvalidToken()
        elif resp.status == 502:
            raise NetworkError('Bad Gateway')
        else:
            raise NetworkError('{0} ({1})'.format(message, resp.status))