Offline & Local IPNS

[Stebalien]

Motivation

Users should be able to publish and resolve IPNS records when disconnected from the global network. This is important in two cases:

1. The user is trying to re-resolve content that has been resolved at some point. This is useful for offline document viewing.
2. Two users are offline and are trying to use IPNS.

Proposal

Libp2p Parts: libp2p/notes#16

• Users should be allowed to publish records when offline. This should not produce an error. However, it might produce a warning.
  • Go-ipfs currently allows this with an --allow-offline flag but that's not very user-friendly.
• Users should be allowed to resolve expired records as long as some warning is displayed.

[aschmahmann]

As I mentioned in the other issue, we can deal with offline use by multiple peers of IPNS by just relying on MDNS + the PubSub IPNS router.

However, a big 👍 to modifying our error handling to allow publishing/resolving in non-optimal scenarios and giving users warnings if they want.