Append Announces

[Jorropo]

Hi, I would like to add announces on top of the listen addrs but,
currently if len(announces) > 0 the regular addrs are replaced by the announces :
https://github.com/ipfs/go-ipfs/blob/1bf8a723f95f8ca9bd5f520b0896b7afc9658a53/core/node/libp2p/addrs.go#L55-L59

I would like to create a way for announces to be added to listen addresses, not replace them.
Wich option would be fine to add ?

• Add an .Addresses.AppendAnnounce bool key, if true addrs = append(allAddrs,annAddrs...) else the current logic.
• Add an .Addresses.ExtraAnnounce []ma.Multiaddr wich is always appended after the current logic.
• Replace the current logic by addrs = append(allAddrs,annAddrs...) (breaking change ?).

[aschmahmann]

@Jorropo implementing one of these proposals seems reasonable. It would be helpful to know a little more context around the use case you're working on.

[Jorropo]

@Jorropo implementing one of these proposals seems reasonable. It would be helpful to know a little more context around the use case you're working on.

Really there is none in this case, could be someone running behind a nat without nat traversal and wanting to announce his port forward while still announcing his local addrs.

[TheDiscordian]

@Jorropo It would be helpful to know a little more context around the use case you're working on.

I've run into a need for this when enabling WSS. My current solution is to grab everywhere I'm announcing to, make a big list, then append my 2 new announcements to that list. It'd be a lot more intuitive to be able to just append to the usual generated list (especially with dynamic IPs...).

Explicitly, currently I'm doing this:

"Announce": ["/ip4/127.0.0.1/tcp/4001","/ip4/127.0.0.1/tcp/4011/ws","/ip4/127.0.0.1/udp/4001/quic","/ip4/172.105.103.78/tcp/4001","/ip4/172.105.103.78/tcp/4011/ws","/ip4/172.105.103.78/udp/4001/quic","/ip6/2600:3c04::f03c:92ff:fecf:988b/tcp/4001","/ip6/2600:3c04::f03c:92ff:fecf:988b/tcp/4011/ws","/ip6/2600:3c04::f03c:92ff:fecf:988b/udp/4001/quic","/ip6/::1/tcp/4001","/ip6/::1/tcp/4011/ws","/ip6/::1/udp/4001/quic","/dns4/ipfs.thedisco.zone/tcp/4430/wss","/dns6/ipfs.thedisco.zone/tcp/4430/wss"]

When I think this would make more sense:

"Announce": [],
"ExtraAnnounce": ["/dns4/ipfs.thedisco.zone/tcp/4430/wss","/dns6/ipfs.thedisco.zone/tcp/4430/wss"]

[lidel]

@TheDiscordian see proposed config in #8177 – would appreciate feedback if it is intuitive enough.

[BigLep]

2021-11-12 discussion: we believe this is just waiting until @lidel frees up to get this reviewed/merged.