| import socket |
| try: |
| from select import poll, POLLIN |
| except ImportError: # `poll` doesn't exist on OSX and other platforms |
| poll = False |
| try: |
| from select import select |
| except ImportError: # `select` doesn't exist on AppEngine. |
| select = False |
| |
| |
| def is_connection_dropped(conn): # Platform-specific |
| """ |
| Returns True if the connection is dropped and should be closed. |
| |
| :param conn: |
| :class:`httplib.HTTPConnection` object. |
| |
| Note: For platforms like AppEngine, this will always return ``False`` to |
| let the platform handle connection recycling transparently for us. |
| """ |
| sock = getattr(conn, 'sock', False) |
| if sock is False: # Platform-specific: AppEngine |
| return False |
| if sock is None: # Connection already closed (such as by httplib). |
| return True |
| |
| if not poll: |
| if not select: # Platform-specific: AppEngine |
| return False |
| |
| try: |
| return select([sock], [], [], 0.0)[0] |
| except socket.error: |
| return True |
| |
| # This version is better on platforms that support it. |
| p = poll() |
| p.register(sock, POLLIN) |
| for (fno, ev) in p.poll(0.0): |
| if fno == sock.fileno(): |
| # Either data is buffered (bad), or the connection is dropped. |
| return True |
| |
| |
| # This function is copied from socket.py in the Python 2.7 standard |
| # library test suite. Added to its signature is only `socket_options`. |
| def create_connection(address, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, |
| source_address=None, socket_options=None): |
| """Connect to *address* and return the socket object. |
| |
| Convenience function. Connect to *address* (a 2-tuple ``(host, |
| port)``) and return the socket object. Passing the optional |
| *timeout* parameter will set the timeout on the socket instance |
| before attempting to connect. If no *timeout* is supplied, the |
| global default timeout setting returned by :func:`getdefaulttimeout` |
| is used. If *source_address* is set it must be a tuple of (host, port) |
| for the socket to bind as a source address before making the connection. |
| An host of '' or port 0 tells the OS to use the default. |
| """ |
| |
| host, port = address |
| err = None |
| for res in socket.getaddrinfo(host, port, 0, socket.SOCK_STREAM): |
| af, socktype, proto, canonname, sa = res |
| sock = None |
| try: |
| sock = socket.socket(af, socktype, proto) |
| |
| # If provided, set socket level options before connecting. |
| # This is the only addition urllib3 makes to this function. |
| _set_socket_options(sock, socket_options) |
| |
| if timeout is not socket._GLOBAL_DEFAULT_TIMEOUT: |
| sock.settimeout(timeout) |
| if source_address: |
| sock.bind(source_address) |
| sock.connect(sa) |
| return sock |
| |
| except socket.error as _: |
| err = _ |
| if sock is not None: |
| sock.close() |
| sock = None |
| |
| if err is not None: |
| raise err |
| else: |
| raise socket.error("getaddrinfo returns an empty list") |
| |
| |
| def _set_socket_options(sock, options): |
| if options is None: |
| return |
| |
| for opt in options: |
| sock.setsockopt(*opt) |