Fee antehandler audit and refactor

[yaruwangway]

Summary

Global Fee (or Global Min Fee) is a gaia module which was supplied by TGrade which defines a fee all transactions have to satisfy (except by-pass-msg).

Currently, Gaia has two fees setups: the mininum_gas_price in config/app.toml and a global fee (a list of coins) in param store.

Gaia fee antehandler takes min_gas_price, Global fee into a combined fee requirement. The combined fee:

• takes the higher fees betweenmin_gas_price and global fee if min_gas_price and global_fee have the same denom. Otherwise, take the global fee
• consider the global fee denom as required denom even if global fee is zero coin

Gaia fee antehandler also can bypass bypass-msg(all msgs are bypass msg types and not exceed MaxBypassMinFeeMsgGasUsage), but if bypass-msg still pays fees, gaia fee antehandler will also check the denoms of the fee.

Type

Impact

Proposed Solution

• Audit is needed for the fee antehandler @tac0turtle if sdk team can help ?
  (@mpoke please confirm this is still the case)

• Document bypass-msg Document how fee bypass works #2089

• Refactor global fee module @mpoke

• Provide relayer and validators guidance of fee setups

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For Admin Use

• Not duplicate issue
• Appropriate labels applied
• Appropriate contributors tagged
• Contributor assigned/self-assigned
• Is a spike necessary to map out how the issue should be approached?

[yaruwangway]

Refactor global fee module:

• change global fee from allow zero coins to not allow zero coins
• in sdk 0.47, params store is deprecated, the global fee params need to migrate from params store to its own store. fix: add params migration cosmos-sdk#14992
• from sdk 0.46, we can use buf to refer proto deps registry, rather than copy paste proto files to gaia. https://github.com/cosmos/gaia/tree/v8.0.0-rc/proto

[yaruwangway]

close, in favor of #2228