split a blank host out of the basic host

[marten-seemann]

Fixes #1247.

As suggested by @Stebalien in #1257 (comment).

We probably need to work on naming here. Should we rename the basic package to full?

[vyzo]

lets punt on this for now.

[marten-seemann]

lets punt on this for now

go-libp2p v0.17.0 is out now.

I'd really like to get this into v0.18.0. Not having duplicated code for our hosts is a prerequisite for further refactors.

[vyzo]

yeah, lets do it; base -vs- basic is confusing. Lets also have a blank profile to replace the blankhost.

[vyzo]

or is that not useful?

[vyzo]

looking good, lets introduce the FullHost name.

[vyzo]

I believ we want identify in the base host, the autonat dialer wont work without it.

[Stebalien]

This actually seems pretty clean.

Although, now that i see it... it would be really nice if we just had a truly pluggable host.

[Stebalien]

What happens if we don't do this? I'm asking because:

1. We're going to clobber it in the Basic/Full host.
2. The addresses are going to be wrong here.

[marten-seemann]

@Stebalien Can you elaborate? It would be nice if the base host supported signed records, wouldn't it?

The addresses are only going to wrong if an address factory is used.
Also, in the full host we generate a new record for ourselves, so we'll overwrite the one that the base host generated.

[Stebalien]

The addresses are only going to wrong if an address factory is used.

These records won't update to changing interface or listen addresses.

As a matter of fact, we're unlikely to even be listening on any addresses by the time we run this code. Normally, we construct the host first:

go-libp2p/config/config.go

Lines 215 to 226 in 4400328

	h, err := bhost.NewHost(swrm, &bhost.HostOpts{
	ConnManager: cfg.ConnManager,
	AddrsFactory: cfg.AddrsFactory,
	NATManager: cfg.NATManager,
	EnablePing: !cfg.DisablePing,
	UserAgent: cfg.UserAgent,
	MultiaddrResolver: cfg.MultiaddrResolver,
	EnableHolePunching: cfg.EnableHolePunching,
	HolePunchingOptions: cfg.HolePunchingOptions,
	EnableRelayService: cfg.EnableRelayService,
	RelayServiceOpts: cfg.RelayServiceOpts,
	})

Then we add the transports:

go-libp2p/config/config.go

Lines 243 to 246 in 4400328

	if err := cfg.addTransports(h); err != nil {
	h.Close()
	return nil, err
	}

Then we start listening:

go-libp2p/config/config.go

Lines 250 to 253 in 4400328

	if err := h.Network().Listen(cfg.ListenAddrs...); err != nil {
	h.Close()
	return nil, err
	}

[Stebalien]

I believe we want identify in the base host, the autonat dialer wont work without it.

What does it use identify for?

[vyzo]

actually maybe you are right, it doesnt really care.

[marten-seemann]

Right, the blankhost used by autonat today doesn't have identify.

[BigLep]

2022-08-26 conversation: this turned out to be more than we expected. Core maintainers will take this on sometime in the future.

[MarcoPolo]

Turns out it was a lot more work than expected. But it seems like we may be circling back on this soon. This PR though is really outdated.