Cosmos-sdk: Post-MVP pre-launch IBC tasks

[cwgoes]

"MVP" is the first collection of code merged, and "launch" is the version proposed for Hub deployment.

• [ ] Utilise evidence module types (and possibly evidence handlers) #5305
• [ ] Update to canonical specification-defined encoding for provableStore data (blocked on spec)
• [ ] Update to specification-defined Merkle proof format (blocked on https://github.com/cosmos/ics/issues/282)
• [ ] Integrate with specification test vectors (blocked on spec)
• [x] Implement ICS 20 bank-bridge module #5204
• [ ] Dynamic port allocation.
• [ ] Solo client support

[tnachen]

• Blocked on evidence module -> That's #4826 right?
• Update to canonical specification-defined encoding for provableStore data (blocked on spec) -> Do we have a github issue on the spec side?
• Integrate with specification test vectors -> Do we have a github issue on the spec side?
• ICS 20 bank-bridge module -> I'll create a Github issue then.

[cwgoes]

• #4826 is just the ADR, this will be blocked on the implementation.
• Spec-side issue for canonical encodings: https://github.com/cosmos/ics/issues/275
• Spec-side issue for test vectors: https://github.com/cosmos/ics/issues/137

[cwgoes]

IRIS has started on the bank-bridge module, and I have reviewed it: https://github.com/cosmos/cosmos-sdk/pull/5204

[cwgoes]

@marbar3778 suggested that we call it the "bank packet handling module".

I tend to agree, "bridge module" evokes PoW bridges, which this is not.

[cwgoes]

I am working on the specification compliance test vectors in https://github.com/cosmos/ics/pull/291.

I expect an initial version sometime next week (when SFBW may cause busy-ness, so no rush) - at that point, it will be possible for the SDK to import a Go shim and test all the specified IBC functions against canonical test vectors.

[cwgoes]

Note that the SDK is currently implementing v1.0.0-rc4 of the IBC spec.

There is already a v1.0.0-rc5, and there will be another release candidate or two prior to finalisation.

I expect it will be most efficient for the SDK to test & polish the current version before upgrading to the latest spec; this is fine, they can proceed in parallel.

You can always find all the spec releases here.

[cwgoes]

Suggested additions by @zmanian et al.

• [ ] Dynamic port allocation.
• [ ] Solo client support

[jackzampolin]

Can we consolidate this issue into https://github.com/cosmos/cosmos-sdk/issues/5125?

[jackzampolin]

Closing this in favor of #5125 where I have also moved these items.

[cwgoes]

Thanks @jackzampolin, I updated #5125 a bit. I think it's comprehensive now.