go-clock migration

[guillaumemichel]

Context

• github.com/benbjohnson/clock has been archived 2 years ago
• Migrate to the maintained fork github.com/filecoin-project/go-clock
• Fixes move away from benjohnson/clock #3289

Depends on

• go-clock migration go-flow-metrics#36

Notes

This PR is only removing direct dependencies. Some indirect dependency on github.com/benbjohnson/clock are remaining, but they are trickier to remove, since some are circular dependencies (e.g go-libp2p-pubsub depends on go-libp2p/net/p2p/connmgr here).

I suggest we migrate the dependency iteratively, first remove direct dependencies from go-libp2p, after the release migrate libraries to use the latest go-libp2p and filecoin-project/go-clock, and finally update go-libp2p to use the latest libs depending on its latest version.

[MarcoPolo]

I previously thought this only affected our tests. Now I realize this affects libp2p users using the connmgr. This means downstream users now must add filecoin-project/go-clock as a dependency. I don't think this is good.

I suggest we:

1. Revert this change.
2. Make a new package in core/clock that has the Clock interface we are already using elsewhere that fixes some subtle footguns in the go-clock library .
3. Update our usages of go-clock to use that new package and consolidate our existing usages.

cc @guillaumemichel

[guillaumemichel]

downstream users now must add filecoin-project/go-clock as a dependency. I don't think this is good.

Why? They already depended on github.com/benbjohnson/clock, so this doesn't add a new dependency.

Update our usages of go-clock to use that new package and consolidate our existing usages.

I am not familiar with the go-libp2p Clock interface, but you say it has feature parity for our use cases with github.com/benbjohnson/clock?

[MarcoPolo]

Why? They already depended on github.com/benbjohnson/clock, so this doesn't add a new dependency.

Even if it was simply a 1:1 copy, it changes the imports. It's effectively a new dependency. There also may be users that don't want to import from the filecoin-project org.

I am not familiar with the go-libp2p Clock interface, but you say it has feature parity for our use cases with github.com/benbjohnson/clock?

It should, or, if not, should be very easy to add missing methods.

[MarcoPolo]

Note that I think this is a blocker for the next release.