module.go

/*
The txfees modules allows nodes to easily support many
tokens for usage as txfees, while letting node operators
only specify their tx fee parameters for a single "base" asset.

- Adds a whitelist of tokens that can be used as fees on the chain.
- Any token not on this list cannot be provided as a tx fee.
- Adds a new SDK message for creating governance proposals for adding new TxFee denoms.
*/
package txfees

import (
	"context"
	"encoding/json"
	"fmt"

	"github.com/gorilla/mux"
	"github.com/grpc-ecosystem/grpc-gateway/runtime"
	"github.com/spf13/cobra"
	abci "github.com/tendermint/tendermint/abci/types"

	"github.com/cosmos/cosmos-sdk/client"
	"github.com/cosmos/cosmos-sdk/codec"
	cdctypes "github.com/cosmos/cosmos-sdk/codec/types"
	sdk "github.com/cosmos/cosmos-sdk/types"
	"github.com/cosmos/cosmos-sdk/types/module"

	"github.com/osmosis-labs/osmosis/v14/x/txfees/client/cli"
	"github.com/osmosis-labs/osmosis/v14/x/txfees/keeper"
	"github.com/osmosis-labs/osmosis/v14/x/txfees/types"
)

var (
	_ module.AppModule      = AppModule{}
	_ module.AppModuleBasic = AppModuleBasic{}
)

const ModuleName = types.ModuleName

// ----------------------------------------------------------------------------
// AppModuleBasic
// ----------------------------------------------------------------------------

// AppModuleBasic implements the AppModuleBasic interface for the txfees module.
type AppModuleBasic struct{}

func NewAppModuleBasic() AppModuleBasic {
	return AppModuleBasic{}
}

// Name returns the txfees module's name.
func (AppModuleBasic) Name() string {
	return types.ModuleName
}

func (AppModuleBasic) RegisterLegacyAminoCodec(cdc *codec.LegacyAmino) {
	types.RegisterLegacyAminoCodec(cdc)
}

// RegisterInterfaces registers the module's interface types.
func (a AppModuleBasic) RegisterInterfaces(reg cdctypes.InterfaceRegistry) {
	types.RegisterInterfaces(reg)
}

// DefaultGenesis returns the txfees module's default genesis state.
func (AppModuleBasic) DefaultGenesis(cdc codec.JSONCodec) json.RawMessage {
	return cdc.MustMarshalJSON(types.DefaultGenesis())
}

// ValidateGenesis performs genesis state validation for the txfee module.
func (AppModuleBasic) ValidateGenesis(cdc codec.JSONCodec, config client.TxEncodingConfig, bz json.RawMessage) error {
	var genState types.GenesisState
	if err := cdc.UnmarshalJSON(bz, &genState); err != nil {
		return fmt.Errorf("failed to unmarshal %s genesis state: %w", types.ModuleName, err)
	}
	return genState.Validate()
}

// RegisterRESTRoutes is a no-op.  Needed to meet AppModuleBasic interface.
func (AppModuleBasic) RegisterRESTRoutes(clientCtx client.Context, rtr *mux.Router) {}

// RegisterGRPCGatewayRoutes registers the gRPC Gateway routes for the module.
func (AppModuleBasic) RegisterGRPCGatewayRoutes(clientCtx client.Context, mux *runtime.ServeMux) {
	//nolint:errcheck
	types.RegisterQueryHandlerClient(context.Background(), mux, types.NewQueryClient(clientCtx))
}

// GetTxCmd returns the txfees module's root tx command.
func (a AppModuleBasic) GetTxCmd() *cobra.Command {
	return cli.NewTxCmd()
}

// GetQueryCmd returns the txfees module's root query command.
func (AppModuleBasic) GetQueryCmd() *cobra.Command {
	return cli.GetQueryCmd()
}

// ----------------------------------------------------------------------------
// AppModule
// ----------------------------------------------------------------------------

// AppModule implements the AppModule interface for the txfees module.
type AppModule struct {
	AppModuleBasic

	keeper keeper.Keeper
}

func NewAppModule(keeper keeper.Keeper) AppModule {
	return AppModule{
		AppModuleBasic: NewAppModuleBasic(),
		keeper:         keeper,
	}
}

// Name returns the txfees module's name.
func (am AppModule) Name() string {
	return am.AppModuleBasic.Name()
}

// Route returns the txfees module's message routing key.
func (am AppModule) Route() sdk.Route {
	return sdk.Route{}
}

// QuerierRoute returns the txfees module's query routing key.
func (AppModule) QuerierRoute() string { return "" }

// LegacyQuerierHandler is a no-op. Needed to meet AppModule interface.
func (am AppModule) LegacyQuerierHandler(legacyQuerierCdc *codec.LegacyAmino) sdk.Querier {
	return func(sdk.Context, []string, abci.RequestQuery) ([]byte, error) {
		return nil, fmt.Errorf("legacy querier not supported for the x/%s module", types.ModuleName)
	}
}

// RegisterServices registers a GRPC query service to respond to the
// module-specific GRPC queries.
func (am AppModule) RegisterServices(cfg module.Configurator) {
	types.RegisterQueryServer(cfg.QueryServer(), keeper.NewQuerier(am.keeper))
}

// RegisterInvariants registers the txfees module's invariants.
func (am AppModule) RegisterInvariants(_ sdk.InvariantRegistry) {}

// InitGenesis performs the txfees module's genesis initialization It returns
// no validator updates.
func (am AppModule) InitGenesis(ctx sdk.Context, cdc codec.JSONCodec, gs json.RawMessage) []abci.ValidatorUpdate {
	var genState types.GenesisState
	// Initialize global index to index in genesis state
	cdc.MustUnmarshalJSON(gs, &genState)
	if genState.Basedenom == "" {
		panic("genState.Basedenom must be set for txfees")
	}

	am.keeper.InitGenesis(ctx, genState)

	return []abci.ValidatorUpdate{}
}

// ExportGenesis returns the txfees module's exported genesis state as raw JSON bytes.
func (am AppModule) ExportGenesis(ctx sdk.Context, cdc codec.JSONCodec) json.RawMessage {
	genState := am.keeper.ExportGenesis(ctx)
	return cdc.MustMarshalJSON(genState)
}

// BeginBlock executes all ABCI BeginBlock logic respective to the txfees module.
func (am AppModule) BeginBlock(_ sdk.Context, _ abci.RequestBeginBlock) {}

// EndBlock executes all ABCI EndBlock logic respective to the txfees module. It
// returns no validator updates.
func (am AppModule) EndBlock(_ sdk.Context, _ abci.RequestEndBlock) []abci.ValidatorUpdate {
	return []abci.ValidatorUpdate{}
}

// ConsensusVersion implements AppModule/ConsensusVersion.
func (AppModule) ConsensusVersion() uint64 { return 1 }