laconicd-deprecated/x/feemarket/spec/09_antehandlers.md

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# AnteHandlers

The `x/feemarket` module provides `AnteDecorator`s that are recursively chained together into a single [`Antehandler`](https://github.com/cosmos/cosmos-sdk/blob/v0.43.0-alpha1/docs/architecture/adr-010-modular-antehandler.md). These decorators perform basic validity checks on an Ethereum or Cosmos SDK transaction, such that it could be thrown out of the transaction Mempool.

Note that the `AnteHandler` is run for every transaction and called on both `CheckTx` and `DeliverTx`.

## Decorators

### `MinGasPriceDecorator`

Rejects Cosmos SDK transactions with transaction fees lower than `MinGasPrice * GasLimit`.

### `EthMinGasPriceDecorator`

Rejects EVM transactions with transactions fees lower than `MinGasPrice * GasLimit`.
    - For `LegacyTx` and `AccessListTx`, the `GasPrice * GasLimit` is used.
    - For EIP-1559 (*aka.* `DynamicFeeTx`), the `EffectivePrice * GasLimit` is used.

::: tip
**Note**: For dynamic transactions, if the `feemarket` formula results in a `BaseFee` that lowers `EffectivePrice < MinGasPrices`, the users must increase the `GasTipCap` (priority fee) until `EffectivePrice > MinGasPrices`. Transactions with `MinGasPrices * GasLimit < transaction fee < EffectiveFee` are rejected by the `feemarket` `AnteHandle`.
:::
-												feemarket: global `MinGasPrice` parameter (#1104)

* Add min_gas_price to feemarket params

* Add MinGasPriceDecorators

* feemarket integration tests for MinGasPrice

* Restructure integration tests

* Simplify integration tests context

We use DeliverTx context to set up the app, otherwise not all settings are initialized.
We test CheckTx with `s.app.BaseApp.CheckTx(req)`, which uses the `CheckTx` mode and context.

* Update MinGasPrice spec in feemarket module

* reorder ethermint module order for initializing genesis

* feemarket migrations for adding MinGasPrice param

* update changelog

* Additional unit tests for MinGasPrice = 0, tx gas price > 0 (PR review)

https://github.com/tharsis/ethermint/pull/1104#discussion_r884991661

* Use 0 MinGasPrice for transaction simulations

* Fix duplicate registration of feemarket GenesisState and Params (PR review)

https://github.com/tharsis/ethermint/pull/1104#issuecomment-1141893712
											
										
										
											2022-05-31 16:28:46 +00:00
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 								# AnteHandlers
 								The `x/feemarket` module provides `AnteDecorator`s that are recursively chained together into a single [`Antehandler`](https://github.com/cosmos/cosmos-sdk/blob/v0.43.0-alpha1/docs/architecture/adr-010-modular-antehandler.md). These decorators perform basic validity checks on an Ethereum or Cosmos SDK transaction, such that it could be thrown out of the transaction Mempool.
 								Note that the `AnteHandler` is run for every transaction and called on both `CheckTx` and `DeliverTx`.
 								## Decorators
 								### `MinGasPriceDecorator`
 								Rejects Cosmos SDK transactions with transaction fees lower than `MinGasPrice * GasLimit`.
 								### `EthMinGasPriceDecorator`
 								Rejects EVM transactions with transactions fees lower than `MinGasPrice * GasLimit`.
 								    - For `LegacyTx` and `AccessListTx`, the `GasPrice * GasLimit` is used.
 								    - For EIP-1559 (*aka.* `DynamicFeeTx`), the `EffectivePrice * GasLimit` is used.
 								::: tip
 								**Note**: For dynamic transactions, if the `feemarket` formula results in a `BaseFee` that lowers `EffectivePrice < MinGasPrices`, the users must increase the `GasTipCap` (priority fee) until `EffectivePrice > MinGasPrices`. Transactions with `MinGasPrices * GasLimit < transaction fee < EffectiveFee` are rejected by the `feemarket` `AnteHandle`.
 								:::