remove peer.IDFromString

[marten-seemann]

This method is almost always used incorrectly. Contrary to what the name indicates, the following does not work:

var id peer.ID
id2 := peer.IDFromString()
// id is not == id2 now!

The reason is that String() encodes the peer ID, so you need to call Decode instead. The existence of this function has cost me hours and hours of debugging, and we continue to use it in places where we shouldn't. We'd be better off if this function didn't exist.

Here's where we got this wrong in go-libp2p: libp2p/go-libp2p#1644
And I'm pretty sure that lotus also got it wrong here: https://github.com/filecoin-project/lotus/blob/1de56d5e470d743e8b1542c889411360c84db431/node/modules/lp2p/libp2p.go#L70-L78 (I haven't followed the entire code path where these peer IDs originate from, but assuming they come from a config file, they're most likely encoded peer IDs)

[github-actions]

gocompat says:

branch 'master' set up to track 'origin/master'.
"github.com/libp2p/go-libp2p-core/peer".IDFromString TopLevelDeclarationDeleted

[vyzo]

not a fan either, but maybe there are (correct) users out there.

@Stebalien ?

[marten-seemann]

Just want to point out, we still have the IDFromBytes method, so those use cases can easily cast their string into a byte slice.

[Stebalien]

We should add a IDFromByteString. Normally, I'd say deprecate. But I'm seeing 99% incorrect uses so yeah.... let's kill it.

We have:

1. One use in go-ipns
2. One use in go-ipfs
3. One incorrect use in the resource manager.
4. One correct use in the routed host (libp2p).
5. Some incorrect uses in lotus.