Modularize or Simplify the eth2 crate

[AgeManning]

Description

The common/eth2 crate appears to import the whole world. Other crates that depend on eth2 are compiling and building libp2p and a whole host of other things.

It would be great if we could significantly reduce the dependency chain here. Either by splitting up some of the structs or removing unnecessary imports.

[dapplion]

I remember asking myself this when doing some PoC a long time ago that depended on common/eth2

[dapplion]

The dependency on libp2p is only for these types

use lighthouse_network::{types::SyncState, PeerInfo};
use lighthouse_network::{ConnectionDirection, Enr, Multiaddr, PeerConnectionStatus};
use lighthouse_network::PeerId;

[hopinheimer]

hi @AgeManning do you think I can swoop in on this?

[dapplion]

From an offline chat with @AgeManning we suggested to:

• Return the serialized ENR as a String to avoid the dependency on discv5
• Import PeerID from its own crate
• Move the misc types SyncState, ConnectionDirection, etc to their own crate of only types and make it a common dependency of lighthouse_network and common/eth2

[SkandaBhat]

If nobody else is working on this, can I take a crack at this? @AgeManning @dapplion

[AgeManning]

Hey @SkandaBhat - Sorry we have been away at a conference.

@hopinheimer are you still looking into this? Or should @SkandaBhat have a crack?

[hopinheimer]

Hey @AgeManning sorry just reached back from the conference.

hi @SkandaBhat please feel free to pick this up I haven't started work on it.

[SkandaBhat]

Sure thanks! @AgeManning please feel free to assign this to me! I am available this week and can create smaller PRs towards this issue.

[Gua00va]

From an offline chat with @AgeManning we suggested to:

• Return the serialized ENR as a String to avoid the dependency on discv5
• Import PeerID from its own crate
• Move the misc types SyncState, ConnectionDirection, etc to their own crate of only types and make it a common dependency of lighthouse_network and common/eth2

@dapplion for the 3rd point, should a new crate be created or should I put it in an existing one?

[dapplion]

for the 3rd point, should a new crate be created or should I put it in an existing one?

You can add a new crate network_types

[dknopik]

Hey @SkandaBhat and @Gua00va, thanks for picking up this issue!

We are currently modularizing some parts of the Lighthouse code base for use in Anchor, and as the eth2 crate is rather central we depend on it getting modularized soon. How is your progress? Let me know if I should take a look at some work in progress :)

[SkandaBhat]

Hey @dknopik I should have a draft by Tuesday next week, does that work?

[dknopik]

@SkandaBhat Sounds great, thanks!

[dknopik]

Hey @SkandaBhat, I already got started a bit today, see PR #6680. Feel free to improve on it if you have some ideas!

[SkandaBhat]

Unfortunately got held up with something else last week @dknopik, I'll check your PR today and see if I have anything I can improve!