x/params: Raw Parameter Querying

CHANGELOG.md

@@ -104,6 +104,7 @@ information on how to implement the new `Keyring` interface.
   * [ICS 023 - Vector Commitments](https://github.com/cosmos/ics/tree/master/spec/ics-023-vector-commitments) subpackage
   * (ibc/ante) Implement IBC `AnteHandler` as per [ADR 15 - IBC Packet Receiver](https://github.com/cosmos/tree/master/docs/architecture/adr-015-ibc-packet-receiver.md).
 * (x/capability) [\#5828](https://github.com/cosmos/cosmos-sdk/pull/5828) Capability module integration as outlined in [ADR 3 - Dynamic Capability Store](https://github.com/cosmos/tree/master/docs/architecture/adr-003-dynamic-capability-store.md).
+* (x/params) [\#6005](https://github.com/cosmos/cosmos-sdk/pull/6005) Add new CLI command for querying raw x/params parameters by subspace and key.
 
 ### Bug Fixes
 

simapp/app.go

@@ -278,6 +278,7 @@ func NewSimApp(
 		upgrade.NewAppModule(app.UpgradeKeeper),
 		evidence.NewAppModule(app.EvidenceKeeper),
 		ibc.NewAppModule(app.IBCKeeper),
+		params.NewAppModule(app.ParamsKeeper),
 		transferModule,
 	)
 
@@ -312,7 +313,7 @@ func NewSimApp(
 		staking.NewAppModule(app.StakingKeeper, app.AccountKeeper, app.BankKeeper, app.SupplyKeeper),
 		distr.NewAppModule(app.DistrKeeper, app.AccountKeeper, app.BankKeeper, app.SupplyKeeper, app.StakingKeeper),
 		slashing.NewAppModule(app.SlashingKeeper, app.AccountKeeper, app.BankKeeper, app.StakingKeeper),
-		params.NewAppModule(), // NOTE: only used for simulation to generate randomized param change proposals
+		params.NewAppModule(app.ParamsKeeper),
 	)
 
 	app.sm.RegisterStoreDecoders()

x/params/alias.go

@@ -8,23 +8,30 @@ import (
 )
 
 const (
-	StoreKey  = types.StoreKey
-	TStoreKey = types.TStoreKey
+	StoreKey     = types.StoreKey
+	TStoreKey    = types.TStoreKey
+	ModuleName   = types.ModuleName
+	QuerierRoute = types.QuerierRoute
 )
 
 var (
 	// functions aliases
-	NewKeeper       = keeper.NewKeeper
-	NewParamSetPair = types.NewParamSetPair
-	NewKeyTable     = types.NewKeyTable
+	NewKeeper                 = keeper.NewKeeper
+	NewParamSetPair           = types.NewParamSetPair
+	NewKeyTable               = types.NewKeyTable
+	NewQuerySubspaceParams    = types.NewQuerySubspaceParams
+	NewQuerier                = keeper.NewQuerier
+	NewSubspaceParamsResponse = types.NewSubspaceParamsResponse
 )
 
 type (
-	Keeper           = keeper.Keeper
-	ParamSetPair     = types.ParamSetPair
-	ParamSetPairs    = types.ParamSetPairs
-	ParamSet         = types.ParamSet
-	Subspace         = types.Subspace
-	ReadOnlySubspace = types.ReadOnlySubspace
-	KeyTable         = types.KeyTable
+	Keeper                 = keeper.Keeper
+	ParamSetPair           = types.ParamSetPair
+	ParamSetPairs          = types.ParamSetPairs
+	ParamSet               = types.ParamSet
+	Subspace               = types.Subspace
+	ReadOnlySubspace       = types.ReadOnlySubspace
+	KeyTable               = types.KeyTable
+	QuerySubspaceParams    = types.QuerySubspaceParams
+	SubspaceParamsResponse = types.SubspaceParamsResponse
 )

x/params/client/cli/query.go

@@ -0,0 +1,63 @@
+package cli
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/client/context"
+	"github.com/cosmos/cosmos-sdk/client/flags"
+	"github.com/cosmos/cosmos-sdk/codec"
+	"github.com/cosmos/cosmos-sdk/x/params/types"
+)
+
+// NewQueryCmd returns a root CLI command handler for all x/params query commands.
+func NewQueryCmd(m codec.Marshaler) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:                        types.ModuleName,
+		Short:                      "Querying commands for the params module",
+		DisableFlagParsing:         true,
+		SuggestionsMinimumDistance: 2,
+		RunE:                       client.ValidateCmd,
+	}
+
+	cmd.AddCommand(NewQuerySubspaceParamsCmd(m))
+
+	return cmd
+}
+
+// NewQuerySubspaceParamsCmd returns a CLI command handler for querying subspace
+// parameters managed by the x/params module.
+func NewQuerySubspaceParamsCmd(m codec.Marshaler) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "subspace [subspace] [key]",
+		Short: "Query for raw parameters by subspace and key",
+		Args:  cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			cliCtx := context.NewCLIContext().WithMarshaler(m)
+
+			params := types.NewQuerySubspaceParams(args[0], args[1])
+			route := fmt.Sprintf("custom/%s/%s", types.QuerierRoute, types.QueryParams)
+
+			bz, err := m.MarshalJSON(params)
+			if err != nil {
+				return fmt.Errorf("failed to marshal params: %w", err)
+			}
+
+			bz, _, err = cliCtx.QueryWithData(route, bz)
+			if err != nil {
+				return err
+			}
+
+			var resp types.SubspaceParamsResponse
+			if err := m.UnmarshalJSON(bz, &resp); err != nil {
+				return err
+			}
+
+			return cliCtx.PrintOutput(resp)
+		},
+	}
+
+	return flags.GetCommands(cmd)[0]
+}

x/params/keeper/querier.go

@@ -0,0 +1,47 @@
+package keeper
+
+import (
+	abci "github.com/tendermint/tendermint/abci/types"
+
+	"github.com/cosmos/cosmos-sdk/codec"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	"github.com/cosmos/cosmos-sdk/x/params/types"
+	"github.com/cosmos/cosmos-sdk/x/params/types/proposal"
+)
+
+// NewQuerier returns a new querier handler for the x/params module.
+func NewQuerier(k Keeper) sdk.Querier {
+	return func(ctx sdk.Context, path []string, req abci.RequestQuery) ([]byte, error) {
+		switch path[0] {
+		case types.QueryParams:
+			return queryParams(ctx, req, k)
+
+		default:
+			return nil, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "unknown query path: %s", path[0])
+		}
+	}
+}
+
+func queryParams(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, error) {
+	var params types.QuerySubspaceParams
+
+	if err := codec.Cdc.UnmarshalJSON(req.Data, &params); err != nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONUnmarshal, err.Error())
+	}
+
+	ss, ok := k.GetSubspace(params.Subspace)
+	if !ok {
+		return nil, sdkerrors.Wrap(proposal.ErrUnknownSubspace, params.Subspace)
+	}
+
+	rawValue := ss.GetRaw(ctx, []byte(params.Key))
+	resp := types.NewSubspaceParamsResponse(params.Subspace, params.Key, string(rawValue))
+
+	bz, err := codec.MarshalJSONIndent(codec.Cdc, resp)
+	if err != nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
+	}
+
+	return bz, nil
+}

x/params/module.go

@@ -6,6 +6,7 @@ import (
 
 	"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"
@@ -17,6 +18,7 @@ import (
 )
 
 var (
+	_ module.AppModule           = AppModule{}
 	_ module.AppModuleBasic      = AppModuleBasic{}
 	_ module.AppModuleSimulation = AppModule{}
 )
@@ -55,21 +57,38 @@ func (AppModuleBasic) GetQueryCmd(_ *codec.Codec) *cobra.Command { return nil }
 // AppModule implements an application module for the distribution module.
 type AppModule struct {
 	AppModuleBasic
+
+	keeper Keeper
 }
 
 // NewAppModule creates a new AppModule object
-func NewAppModule() AppModule {
+func NewAppModule(k Keeper) AppModule {
 	return AppModule{
 		AppModuleBasic: AppModuleBasic{},
+		keeper:         k,
 	}
 }
 
-//____________________________________________________________________________
+func (am AppModule) RegisterInvariants(_ sdk.InvariantRegistry) {}
 
-// AppModuleSimulation functions
+func (am AppModule) NewHandler() sdk.Handler { return nil }
+
+// InitGenesis performs a no-op.
+func (am AppModule) InitGenesis(_ sdk.Context, _ codec.JSONMarshaler, _ json.RawMessage) []abci.ValidatorUpdate {
+	return []abci.ValidatorUpdate{}
+}
+
+func (AppModule) Route() string { return "" }
 
 // GenerateGenesisState performs a no-op.
-func (AppModule) GenerateGenesisState(simState *module.SimulationState) {
+func (AppModule) GenerateGenesisState(simState *module.SimulationState) {}
+
+// QuerierRoute returns the x/param module's querier route name.
+func (AppModule) QuerierRoute() string { return QuerierRoute }
+
+// NewQuerierHandler returns the x/params querier handler.
+func (am AppModule) NewQuerierHandler() sdk.Querier {
+	return NewQuerier(am.keeper)
 }
 
 // ProposalContents returns all the params content functions used to
@@ -90,3 +109,16 @@ func (AppModule) RegisterStoreDecoder(sdr sdk.StoreDecoderRegistry) {}
 func (am AppModule) WeightedOperations(_ module.SimulationState) []simtypes.WeightedOperation {
 	return nil
 }
+
+// ExportGenesis performs a no-op.
+func (am AppModule) ExportGenesis(_ sdk.Context, _ codec.JSONMarshaler) json.RawMessage {
+	return nil
+}
+
+// BeginBlock performs a no-op.
+func (AppModule) BeginBlock(_ sdk.Context, _ abci.RequestBeginBlock) {}
+
+// EndBlock performs a no-op.
+func (AppModule) EndBlock(_ sdk.Context, _ abci.RequestEndBlock) []abci.ValidatorUpdate {
+	return []abci.ValidatorUpdate{}
+}

x/params/types/keys.go

@@ -0,0 +1,9 @@
+package types
+
+const (
+	// ModuleName defines the module name
+	ModuleName = "params"
+
+	// QuerierRoute defines the module's query routing key
+	QuerierRoute = ModuleName
+)

x/params/types/querier.go

@@ -0,0 +1,35 @@
+package types
+
+// Querier path constants
+const (
+	QueryParams = "params"
+)
+
+// QuerySubspaceParams defines the params for querying module params by a given
+// subspace and key.
+type QuerySubspaceParams struct {
+	Subspace string
+	Key      string
+}
+
+// SubspaceParamsResponse defines the response for quering parameters by subspace.
+type SubspaceParamsResponse struct {
+	Subspace string
+	Key      string
+	Value    string
+}
+
+func NewQuerySubspaceParams(ss, key string) QuerySubspaceParams {
+	return QuerySubspaceParams{
+		Subspace: ss,
+		Key:      key,
+	}
+}
+
+func NewSubspaceParamsResponse(ss, key, value string) SubspaceParamsResponse {
+	return SubspaceParamsResponse{
+		Subspace: ss,
+		Key:      key,
+		Value:    value,
+	}
+}