The IBC ibc crate should be no-std

[zmanian]

Summary

The relayer-modules crate should be no-std.

Problem Definition

The relayer-modules crate should support no-std this would make it more useful for solo nodes running in embedded environments and integrating deployment in wasm environments like Substrate Pallets and Eth2 Execution Environments.

Proposal

Ideally the full relayer can be in std environment and use crates like tokio.

There is progress in support unclear how this interacts with using core::future in the API. Needs more inverstigation.

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For Admin Use

• Not duplicate issue
• Appropriate labels applied
• Appropriate contributors tagged
• Contributor assigned/self-assigned

[hxrts]

The cdot team raised this same issue as Substrate uses no-std.

[adizere]

We'd like to understand the priority for this issue. Suppose we adapt the modules crate to no-std in the second trimester of 2021 (after may, before end of august), would that work?

[hxrts]

@en @livelybug @toliuyi maybe you can comment on whether this is blocking, or a feature that's nice-to-have?

[en]

Sorry, I submitted a duplicate issue( #508 ) today because I missed the notification.
I think this issue will not block the current integration work. Once ibc-rs supports no_std, substrate-ibc will support no_std without modification.

[andynog]

the no_std support on tendermint-rs repo -> informalsystems/tendermint-rs#824

[adizere]

#1158 thoroughly tracks efforts towards no_std. Closing as duplicate of that.