Allow configuration for IPv4 binding

[Sytten]

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Ory Network Project

No response

Describe your problem

Golang by default binds to IPv6, which doesn't work for everybody.
It would be nice if we could specify tcp4 for:

x/networkx/listener.go

Line 30 in 6511eb1

return net.Listen("tcp", address)

Describe your ideal solution

Ideally the parent service config can pass down an override for the IPv4 vs IPv6 binding with a default to IPv6.
I can push the PR, but I am not sure if we want to offer another function to avoid a breaking change in the interface.

func MakeListener(network string, address string, socketPermission *configx.UnixPermission) (net.Listener, error)

Workarounds or alternatives

There is none right now.

Version

Kratos 1.1.0

Additional Context

No response

[alnr]

This should be possible by specifying an IPv4 literal as the listening address, no?

Please reopen if I'm mistaken.

[Sytten]

You are mistaken, by default it will always use IPv6 even with an IPv4 address is given at least for common cases like 0.0.0.0

[alnr]

Confirmed, and very weird. Go listens on IPv6 given net.Listen("tcp", "0.0.0.0:0").

We can't change any interfaces.

On my machine, net.Listen("tcp", "127.0.0.1:0") binds a IPv4 address. So the problem is probably only acute if you want to listen on all IPv4 addresses (which is not currently possible)?

We could add a special case just for "0.0.0.0" and force IPv4 in that case. WDYT?