Function bind_sockets

tornado/netutil.py:56–187

Creates listening sockets bound to the given port and address. Returns a list of socket objects (multiple sockets are returned if the given address maps to multiple IP addresses, which is most common for mixed IPv4 and IPv6 use). Address may be either an IP address or hostname. If

(
    port: int,
    address: Optional[str] = None,
    family: socket.AddressFamily = socket.AF_UNSPEC,
    backlog: int = _DEFAULT_BACKLOG,
    flags: Optional[int] = None,
    reuse_port: bool = False,
)

def bind_sockets(
    port: int,
    address: Optional[str] = None,
    family: socket.AddressFamily = socket.AF_UNSPEC,
    backlog: int = _DEFAULT_BACKLOG,
    flags: Optional[int] = None,
    reuse_port: bool = False,
) -> List[socket.socket]:
    """Creates listening sockets bound to the given port and address.

    Returns a list of socket objects (multiple sockets are returned if
    the given address maps to multiple IP addresses, which is most common
    for mixed IPv4 and IPv6 use).

    Address may be either an IP address or hostname.  If it's a hostname,
    the server will listen on all IP addresses associated with the
    name.  Address may be an empty string or None to listen on all
    available interfaces.  Family may be set to either `socket.AF_INET`
    or `socket.AF_INET6` to restrict to IPv4 or IPv6 addresses, otherwise
    both will be used if available.

    The ``backlog`` argument has the same meaning as for
    `socket.listen() <socket.socket.listen>`.

    ``flags`` is a bitmask of AI_* flags to `~socket.getaddrinfo`, like
    ``socket.AI_PASSIVE | socket.AI_NUMERICHOST``.

    ``reuse_port`` option sets ``SO_REUSEPORT`` option for every socket
    in the list. If your platform doesn&#x27;t support this option ValueError will
    be raised.
    """
    if reuse_port and not hasattr(socket, "SO_REUSEPORT"):
        raise ValueError("the platform doesn't support SO_REUSEPORT")

    sockets = []
    if address == "":
        address = None
    if not socket.has_ipv6 and family == socket.AF_UNSPEC:
        # Python can be compiled with --disable-ipv6, which causes
        # operations on AF_INET6 sockets to fail, but does not
        # automatically exclude those results from getaddrinfo
        # results.
        # http://bugs.python.org/issue16208
        family = socket.AF_INET
    if flags is None:
        flags = socket.AI_PASSIVE
    bound_port = None
    unique_addresses = set()  # type: set
    for res in sorted(
        socket.getaddrinfo(address, port, family, socket.SOCK_STREAM, 0, flags),
        key=lambda x: x[0],
    ):
        if res in unique_addresses:
            continue

        unique_addresses.add(res)

        af, socktype, proto, canonname, sockaddr = res