Our scaffold tool has done most of the work for us in generating our module.go file inside ./nfts/. One way that our module is different than the simplest form of a module, is that it uses it's own Keeper. The only real changes needed are under the AppModule and NewAppModule. The file should look as follows afterward:
package nfts
import (
"encoding/json"
"fmt"
"github.com/gorilla/mux"
"github.com/spf13/cobra"
abci "github.com/tendermint/tendermint/abci/types"
"github.com/cosmos/cosmos-sdk/client/context"
"github.com/cosmos/cosmos-sdk/codec"
sdk "github.com/cosmos/cosmos-sdk/types"
"github.com/cosmos/cosmos-sdk/types/module"
"github.com/FreeFlixMedia/modules/nfts/client/cli"
"github.com/FreeFlixMedia/modules/nfts/internal/types"
)
var (
_ module.AppModule = AppModule{}
_ module.AppModuleBasic = AppModuleBasic{}
)
type AppModuleBasic struct{}
func (AppModuleBasic) Name() string {
return types.ModuleName
}
func (AppModuleBasic) RegisterCodec(cdc *codec.Codec) {
types.RegisterCodec(cdc)
}
func (AppModuleBasic) DefaultGenesis(cdc codec.JSONMarshaler) json.RawMessage {
return cdc.MustMarshalJSON(types.DefaultGenesisState())
}
func (AppModuleBasic) ValidateGenesis(cdc codec.JSONMarshaler, bz json.RawMessage) error {
var data types.GenesisState
if err := cdc.UnmarshalJSON(bz, &data); err != nil {
return fmt.Errorf("failed to unmarshal %s genesis state: %w", types.ModuleName, err)
}
return data.ValidateGenesis()
}
func (AppModuleBasic) RegisterRESTRoutes(ctx context.CLIContext, rtr *mux.Router) {
}
func (AppModuleBasic) GetTxCmd(cdc *codec.Codec) *cobra.Command {
return cli.GetTxCmd(cdc)
}
func (AppModuleBasic) GetQueryCmd(cdc *codec.Codec) *cobra.Command {
return cli.GetQueryCmd(cdc)
}
type AppModule struct {
AppModuleBasic
nftKeeper Keeper
}
func NewAppModule(keeper Keeper) AppModule {
return AppModule{
nftKeeper: keeper,
}
}
func (AppModule) Name() string {
return ModuleName
}
func (AppModule) RegisterInvariants(_ sdk.InvariantRegistry) {}
func (AppModule) Route() string { return RouterKey }
func (am AppModule) NewHandler() sdk.Handler { return NewHandler(am.nftKeeper) }
func (AppModule) QuerierRoute() string {
return types.QuerierRoute
}
func (am AppModule) NewQuerierHandler() sdk.Querier {
return NewQuerier(am.nftKeeper)
}
func (am AppModule) InitGenesis(ctx sdk.Context, cdc codec.JSONMarshaler, data json.RawMessage) []abci.ValidatorUpdate {
var genesisState GenesisState
cdc.MustUnmarshalJSON(data, &genesisState)
InitGenesis(ctx, am.nftKeeper, genesisState)
return []abci.ValidatorUpdate{}
}
func (am AppModule) ExportGenesis(ctx sdk.Context, cdc codec.JSONMarshaler) json.RawMessage {
gs := ExportGenesis(ctx, am.nftKeeper)
return cdc.MustMarshalJSON(gs)
}
func (AppModule) BeginBlock(_ sdk.Context, _ abci.RequestBeginBlock) {}
func (AppModule) EndBlock(ctx sdk.Context, _ abci.RequestEndBlock) []abci.ValidatorUpdate {
return []abci.ValidatorUpdate{}
}
Congratulations you have completed the nfts module!
This module is now able to be incorporated into any Cosmos SDK application.
Since we don't want to just build a module but want to build an application that also uses that module, let's go through the process of configuring an app.