EPIC: Refactor modules away from using x/params

[aaronc]

As discussed in #9913

In adr-046, the sdk decided to move away from a param module in favor of having each sdk module handle its own parameters. This is an optional change for applications and the Param module will live on in a deprecated form. The sdk will be migrating the core modules to use this new paradigm.

See https://github.com/cosmos/cosmos-sdk/blob/master/docs/architecture/adr-046-module-params.md for instructions on how to do this.

TODO:

• migrate auth to not use param module #12283
• migrate bank to not use param module #12284
• migrate staking away from param module #12285
• remove params module from x/mint #12286
• remove param module from x/distribution  #12287
• remove params from x/slashing #12288
• remove param module from x/crisis #12445
• feat: deprecate x/params usage in x/gov #12631
• Param deprecation documentation  #12496
• Remove RandomizedParams from the AppModuleSimulation interface. #12497
• module: consensus-param module #12652

[technicallyty]

added @gsk967 to gov per #9979 (comment).

[tac0turtle]

is this blocked on #9438

EDIT: its blocking

[tac0turtle]

Talked with @cmwaters and the ability to list a module as the only one to execute this message is merged into master, unblocking this work. @technicallyty do you still want to kick off this work?

[alexanderbez]

@technicallyty lets work on this together 👍

[technicallyty]

@technicallyty lets work on this together 👍

sounds good!

[gsk967]

@technicallyty Can I start on gov params

[tac0turtle]

Two Open questions that came to me:

• how to handle consensus parameters from tendermint, make base app stateful or role a very simple tendermint param module for these things.
• Do we want deprecate the transient store? The only module using it was the param module.

[alexanderbez]

how to handle consensus parameters from tendermint, make base app stateful or role a very simple tendermint param module for these things.

A dedicated module (e.g. x/consensus or x/consensus-params) with a simple message MsgUpdatePararms and a message server -- nothing else.

Do we want deprecate the transient store? The only module using it was the param module.

Yes, I believe so.

[amaury1093]

A dedicated module (e.g. x/consensus or x/consensus-params) with a simple message MsgUpdatePararms and a message serve -- nothing else.

Agreed. The tricky part is how to make baseapp aware of this module. Baseapp should obviously not depend on x/consensus-params, so I guess the correct dep is the other way round, e.g. a simple setter on BaseApp that would be called from inside x/consensus-params (similar to how x/upgrade updates the AppVersion in baseapp)

[alexanderbez]

@AmauryM why can't we just provide an interface/generics type to BaseApp (that the keeper implements)?

[amaury1093]

Yeah, that works too 👍