feat: create v12-commission-fix upgrade (#286)

## Description

Closes: #XXXX

<!-- Add a description of the changes that this PR introduces and the
files that
are the most critical to review. -->

---

### Author Checklist

*All items are required. Please add a note to the item if the item is
not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR
Targeting](https://github.com/milkyway-labs/milkyway/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building
modules](https://docs.cosmos.network/v0.44/building-modules/intro.html)
- [ ] included the necessary unit and integration
[tests](https://github.com/milkyway-labs/milkyway/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go
code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable
and please add
your handle next to the items reviewed if you only reviewed selected
items.*

I have...

- [ ] confirmed the correct [type
prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json)
in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **New Features**
- Introduced a new upgrade to enforce a global minimum commission rate
for all validators. During the upgrade, any validator with a commission
rate or maximum commission rate below the minimum will have their rates
automatically adjusted to meet the required threshold.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: hallazzang

app/app.go

@@ -71,6 +71,7 @@ import (
 	v11 "github.com/milkyway-labs/milkyway/v12/app/upgrades/v11"
 	v11warpfix "github.com/milkyway-labs/milkyway/v12/app/upgrades/v11-warp-fix"
 	v12 "github.com/milkyway-labs/milkyway/v12/app/upgrades/v12"
+	v12commissionfix "github.com/milkyway-labs/milkyway/v12/app/upgrades/v12-commission-fix"
 	v6 "github.com/milkyway-labs/milkyway/v12/app/upgrades/v6"
 	v9 "github.com/milkyway-labs/milkyway/v12/app/upgrades/v9"
 	_ "github.com/milkyway-labs/milkyway/v12/client/docs/statik"
@@ -93,6 +94,7 @@ var (
 		v11.Upgrade,
 		v11warpfix.Upgrade,
 		v12.Upgrade,
+		v12commissionfix.Upgrade,
 	}
 )
 

app/upgrades/v12-commission-fix/constants.go

@@ -0,0 +1,18 @@
+package v12commissionfix
+
+import (
+	storetypes "cosmossdk.io/store/types"
+
+	"github.com/milkyway-labs/milkyway/v12/app/upgrades"
+)
+
+const UpgradeName = "v12-commission-fix"
+
+var Upgrade = upgrades.Upgrade{
+	UpgradeName:          UpgradeName,
+	CreateUpgradeHandler: CreateUpgradeHandler,
+	StoreUpgrades: storetypes.StoreUpgrades{
+		Added:   []string{},
+		Deleted: []string{},
+	},
+}

app/upgrades/v12-commission-fix/upgrades.go

@@ -0,0 +1,53 @@
+package v12commissionfix
+
+import (
+	"context"
+
+	upgradetypes "cosmossdk.io/x/upgrade/types"
+	"github.com/cosmos/cosmos-sdk/types/module"
+
+	"github.com/milkyway-labs/milkyway/v12/app/keepers"
+)
+
+func CreateUpgradeHandler(
+	mm *module.Manager,
+	configuration module.Configurator,
+	keepers *keepers.AppKeepers,
+) upgradetypes.UpgradeHandler {
+	return func(ctx context.Context, plan upgradetypes.Plan, fromVM module.VersionMap) (module.VersionMap, error) {
+		vm, err := mm.RunMigrations(ctx, configuration, fromVM)
+		if err != nil {
+			return nil, err
+		}
+
+		// Get the global minimum commission rate.
+		stakingParams, err := keepers.StakingKeeper.GetParams(ctx)
+		if err != nil {
+			return nil, err
+		}
+		minCommissionRate := stakingParams.MinCommissionRate
+
+		// Update all validators' commssion rate and max commission rate to match the
+		// global minimum commission rate.
+		validators, err := keepers.StakingKeeper.GetAllValidators(ctx)
+		if err != nil {
+			return nil, err
+		}
+		for _, validator := range validators {
+			// If the validator's commission rate and maximum commission rate are less than
+			// the global minimum commission rate, increase them.
+			if validator.Commission.MaxRate.LT(minCommissionRate) {
+				validator.Commission.MaxRate = minCommissionRate
+			}
+			if validator.Commission.Rate.LT(minCommissionRate) {
+				validator.Commission.Rate = minCommissionRate
+			}
+			err = keepers.StakingKeeper.SetValidator(ctx, validator)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		return vm, nil
+	}
+}