Add socket module

[Wescoeur]

Must be merged after #20.

[Millefeuille42]

One non-blocking suggestion.

[Millefeuille42]

I'd suggest using enums.

Either a single one by doing a complex enum class:

class AddressFamily(Enum):
    # (member name) = (family, ip_version, display_str)
    IPV4 = (socket.AF_INET, 4, "IPv4")
    IPV6 = (socket.AF_INET6, 6, "IPv6")
    UNIX = (socket.AF_UNIX, None, "Unix")
    UNSPEC = (socket.AF_UNSPEC, 0, "Unknown")

    def __init__(self, family: socket.AddressFamily, ip_version: int, display_str: str):
        self.family = family
        self.ip_version = ip_version
        self.display_str = display_str

    # Build the map on lookup
    @classmethod
    def _missing_(cls: type['AddressFamily'], value: Union[socket.AddressFamily, int, str, None]) -> 'AddressFamily':
        if not hasattr(cls, '_lookup_map'):
            cls._lookup_map: Dict[Union[socket.AddressFamily, int, str], AddressFamily] = {}
            for member in cls:
                cls._lookup_map[str(member.family)] = member
                cls._lookup_map[member.display_str] = member
                if member.ip_version is None:
                    cls._lookup_map[str(member.ip_version)] = member
                else:
                    cls._lookup_map[member.ip_version] = member

        # cast to str to prevent collision between family (which is an int) and ip_version
        if value is None or isinstance(value, socket.AddressFamily):
            value = str(value)
        return cls._lookup_map.get(value, cls.UNSPEC)

Usage:

def get_socket_family_str(sock: socket.socket) -> str:
    return AddressFamily(sock.family).display_str

[...]

    family = AddressFamily(ip_version).family

Or using two enums:

class AddressFamily(Enum):
    IPv4 = socket.AF_INET
    IPv6 = socket.AF_INET6
    Unix = socket.AF_UNIX


class IPVersion(Enum):
    IPv4 = 4
    IPv6 = 6
    UNSPEC = 0

    @property
    def family(self) -> int:
        match self:
            case IPVersion.IPv4: return socket.AF_INET
            case IPVersion.IPv6: return socket.AF_INET6
            case IPVersion.UNSPEC: return socket.AF_UNSPEC

Usage:

def get_socket_family_str(sock: socket.socket) -> str:
    return AddressFamily(sock.family).name

[...]

    family = IPVersion(ip_version).family

[Wescoeur]

It sounds like you're suggesting a new API (which, unfortunately, I have no use for) for the code I haven't pushed yet. I'm open to a new contribution to this module, but in that case, additional tests would be required.

For the short to medium term, I simply need functions that allow me to construct an IP address or display information from a socket.

[Millefeuille42]

I understand, no problem. Just to be clear the intent was to push the usage of enums as early as possible in the project when they could be fit.

But indeed this is something than can be sorted out in the longer term if there's a need.

[Kuruyia]

This looks really clean!