[Supplier] refactor: SupplierStakingFee var usage to param usage (#948

)

## Summary

Replace usage of `supplierkeeper.SupplierStakingFee` with the new param
and delete it.

## Issue

- `TODO_BETA`

## Type of change

Select one or more from the following:

- [ ] New feature, functionality or library
- [ ] Consensus breaking; add the `consensus-breaking` label if so. See
#791 for details
- [ ] Bug fix
- [x] Code health or cleanup
- [ ] Documentation
- [ ] Other (specify)

## Testing

- [ ] **Documentation**: `make docusaurus_start`; only needed if you
make doc changes
- [x] **Unit Tests**: `make go_develop_and_test`
- [ ] **LocalNet E2E Tests**: `make test_e2e`
- [x] **DevNet E2E Tests**: Add the `devnet-test-e2e` label to the PR.

## Sanity Checklist

- [x] I have tested my changes using the available tooling
- [ ] I have commented my code
- [x] I have performed a self-review of my own code; both comments &
source code
- [ ] I create and reference any new tickets, if applicable
- [ ] I have left TODOs throughout the codebase, if applicable

---------

Co-authored-by: red-0ne <[email protected]>

x/supplier/keeper/msg_server_stake_supplier.go

@@ -8,18 +8,12 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 
-	"github.com/pokt-network/poktroll/app/volatile"
 	"github.com/pokt-network/poktroll/telemetry"
 	sharedtypes "github.com/pokt-network/poktroll/x/shared/types"
 	suppliertypes "github.com/pokt-network/poktroll/x/supplier/types"
 )
 
-var (
-	// TODO_BETA(@bryanchriswhite): Make supplier staking fee a governance parameter
-	// TODO_BETA(@red-0ne): Update supplier staking documentation to remove the upstaking requirement and introduce the staking fee.
-	SupplierStakingFee = sdk.NewInt64Coin(volatile.DenomuPOKT, 1)
-)
-
+// TODO_BETA(@red-0ne): Update supplier staking documentation to remove the upstaking requirement and introduce the staking fee.
 func (k msgServer) StakeSupplier(ctx context.Context, msg *suppliertypes.MsgStakeSupplier) (*suppliertypes.MsgStakeSupplierResponse, error) {
 	isSuccessful := false
 	defer telemetry.EventSuccessCounter(
@@ -147,7 +141,8 @@ func (k msgServer) StakeSupplier(ctx context.Context, msg *suppliertypes.MsgStak
 	}
 
 	// Send the coins from the message signer account to the staked supplier pool
-	stakeWithFee := sdk.NewCoins(coinsToEscrow.Add(SupplierStakingFee))
+	supplierStakingFee := k.GetParams(ctx).StakingFee
+	stakeWithFee := sdk.NewCoins(coinsToEscrow.Add(*supplierStakingFee))
 	err = k.bankKeeper.SendCoinsFromAccountToModule(ctx, msgSignerAddress, suppliertypes.ModuleName, stakeWithFee)
 	if err != nil {
 		logger.Info(fmt.Sprintf("ERROR: could not send %v coins from %q to %q module account due to %v", coinsToEscrow, msgSignerAddress, suppliertypes.ModuleName, err))

x/supplier/keeper/msg_server_stake_supplier_test.go

@@ -64,7 +64,8 @@ func TestMsgServer_StakeSupplier_SuccessfulCreateAndUpdate(t *testing.T) {
 	require.Len(t, foundSupplier.Services[0].Endpoints, 1)
 	require.Equal(t, "http://localhost:8080", foundSupplier.Services[0].Endpoints[0].Url)
 	// Assert that the supplier's account balance was reduced by the staking fee
-	balanceDecrease := keeper.SupplierStakingFee.Amount.Int64() + foundSupplier.Stake.Amount.Int64()
+	supplierStakingFee := supplierModuleKeepers.Keeper.GetParams(ctx).StakingFee
+	balanceDecrease := supplierStakingFee.Amount.Int64() + foundSupplier.Stake.Amount.Int64()
 	// SupplierBalanceMap reflects the relative changes to the supplier's balance
 	// (i.e. it starts from 0 and can go below it).
 	// It is not using coins that enforce non-negativity of the balance nor account

x/supplier/keeper/msg_server_unstake_supplier_test.go

@@ -392,7 +392,8 @@ func TestMsgServer_UnstakeSupplier_OperatorCanUnstake(t *testing.T) {
 
 	// Balance decrease is the total amount deducted from the supplier's balance, including
 	// the initial stake and the staking fee.
-	balanceDecrease := keeper.SupplierStakingFee.Amount.Int64() + foundSupplier.Stake.Amount.Int64()
+	supplierStakingFee := supplierModuleKeepers.Keeper.GetParams(ctx).StakingFee
+	balanceDecrease := supplierStakingFee.Amount.Int64() + foundSupplier.Stake.Amount.Int64()
 	// Ensure that the initial stake is not returned to the owner yet
 	require.Equal(t, -balanceDecrease, supplierModuleKeepers.SupplierBalanceMap[ownerAddr])
 
@@ -415,5 +416,5 @@ func TestMsgServer_UnstakeSupplier_OperatorCanUnstake(t *testing.T) {
 
 	// Ensure that the initial stake is returned to the owner while the staking fee
 	// remains deducted from the supplier's balance.
-	require.Equal(t, -keeper.SupplierStakingFee.Amount.Int64(), supplierModuleKeepers.SupplierBalanceMap[ownerAddr])
+	require.Equal(t, -supplierStakingFee.Amount.Int64(), supplierModuleKeepers.SupplierBalanceMap[ownerAddr])
 }