feat(bank): Add secondary query for bank metadata

CHANGELOG.md

@@ -66,6 +66,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/distribution) [#16607](https://github.com/cosmos/cosmos-sdk/pull/16607) use collections for `ValidatorHistoricalRewards` state management:
     * remove `Keeper`: `IterateValidatorHistoricalRewards`, `GetValidatorHistoricalRewards`, `SetValidatorHistoricalRewards`, `DeleteValidatorHistoricalRewards`, `DeleteValidatorHistoricalReward`, `DeleteAllValidatorHistoricalRewards`
 * (x/staking) [#16795](https://github.com/cosmos/cosmos-sdk/pull/16795) `DelegationToDelegationResponse`, `DelegationsToDelegationResponses`, `RedelegationsToRedelegationResponses` are no longer exported.
+* (x/module) [#16795](https://github.com/cosmos/cosmos-sdk/pull/16852) Add `DenomMetadataByQueryString` query in bank module to support metadata query by query string.
 * [#16441](https://github.com/cosmos/cosmos-sdk/pull/16441) Params state is migrated to collections. `GetParams` has been removed
 
 ## [v0.50.0-alpha.1](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.50.0-alpha.1) - 2023-06-30

proto/cosmos/bank/v1beta1/query.proto

@@ -83,6 +83,12 @@ service Query {
     option (google.api.http).get               = "/cosmos/bank/v1beta1/denoms_metadata/{denom}";
   }
 
+  // DenomsMetadata queries the client metadata of a given coin denomination.
+  rpc DenomMetadataByQueryString(QueryDenomMetadataByQueryStringRequest)
+      returns (QueryDenomMetadataByQueryStringResponse) {
+    option (cosmos.query.v1.module_query_safe) = true;
+    option (google.api.http).get               = "/cosmos/bank/v1beta1/denoms_metadata_by_query_string";
+  }
   // DenomsMetadata queries the client metadata for all registered coin
   // denominations.
   rpc DenomsMetadata(QueryDenomsMetadataRequest) returns (QueryDenomsMetadataResponse) {
@@ -300,6 +306,20 @@ message QueryDenomMetadataResponse {
   Metadata metadata = 1 [(gogoproto.nullable) = false, (amino.dont_omitempty) = true];
 }
 
+// QueryDenomMetadataByQueryStringRequest is the request type for the Query/DenomMetadata RPC method.
+// Identical with QueryDenomMetadataRequest but receives denom as query string.
+message QueryDenomMetadataByQueryStringRequest {
+  // denom is the coin denom to query the metadata for.
+  string denom = 1;
+}
+
+// QueryDenomMetadataByQueryStringResponse is the response type for the Query/DenomMetadata RPC
+// method. Identical with QueryDenomMetadataResponse but receives denom as query string in request.
+message QueryDenomMetadataByQueryStringResponse {
+  // metadata describes and provides all the client information for the requested token.
+  Metadata metadata = 1 [(gogoproto.nullable) = false, (amino.dont_omitempty) = true];
+}
+
 // QueryDenomOwnersRequest defines the request type for the DenomOwners RPC query,
 // which queries for a paginated set of all account holders of a particular
 // denomination.

x/bank/keeper/grpc_query.go

@@ -225,6 +225,28 @@ func (k BaseKeeper) DenomMetadata(c context.Context, req *types.QueryDenomMetada
 	}, nil
 }
 
+// DenomMetadataByQueryString is identical to DenomMetadata query, but receives request via query string.
+func (k BaseKeeper) DenomMetadataByQueryString(c context.Context, req *types.QueryDenomMetadataByQueryStringRequest) (*types.QueryDenomMetadataByQueryStringResponse, error) {
+	if req == nil {
+		return nil, status.Errorf(codes.InvalidArgument, "empty request")
+	}
+
+	if err := sdk.ValidateDenom(req.Denom); err != nil {
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	}
+
+	ctx := sdk.UnwrapSDKContext(c)
+
+	metadata, found := k.GetDenomMetaData(ctx, req.Denom)
+	if !found {
+		return nil, status.Errorf(codes.NotFound, "client metadata for denom %s", req.Denom)
+	}
+
+	return &types.QueryDenomMetadataByQueryStringResponse{
+		Metadata: metadata,
+	}, nil
+}
+
 // DenomMetadataV2 is identical to DenomMetadata but receives protoreflect types instead of gogo types.  It exists to
 // resolve a cyclic dependency existent between x/auth and x/bank, so that x/auth may call this keeper without
 // depending on x/bank.

x/bank/keeper/grpc_query_test.go

@@ -455,6 +455,83 @@ func (suite *KeeperTestSuite) TestQueryDenomMetadataRequest() {
 	}
 }
 
+func (suite *KeeperTestSuite) TestQueryDenomMetadataByQueryStringRequest() {
+	var (
+		req         *types.QueryDenomMetadataByQueryStringRequest
+		expMetadata = types.Metadata{}
+	)
+
+	testCases := []struct {
+		msg      string
+		malleate func()
+		expPass  bool
+	}{
+		{
+			"empty denom",
+			func() {
+				req = &types.QueryDenomMetadataByQueryStringRequest{}
+			},
+			false,
+		},
+		{
+			"not found denom",
+			func() {
+				req = &types.QueryDenomMetadataByQueryStringRequest{
+					Denom: "foo",
+				}
+			},
+			false,
+		},
+		{
+			"success",
+			func() {
+				expMetadata = types.Metadata{
+					Description: "The native staking token of the Cosmos Hub.",
+					DenomUnits: []*types.DenomUnit{
+						{
+							Denom:    "uatom",
+							Exponent: 0,
+							Aliases:  []string{"microatom"},
+						},
+						{
+							Denom:    "atom",
+							Exponent: 6,
+							Aliases:  []string{"ATOM"},
+						},
+					},
+					Base:    "uatom",
+					Display: "atom",
+				}
+
+				suite.bankKeeper.SetDenomMetaData(suite.ctx, expMetadata)
+				req = &types.QueryDenomMetadataByQueryStringRequest{
+					Denom: expMetadata.Base,
+				}
+			},
+			true,
+		},
+	}
+
+	for _, tc := range testCases {
+		suite.Run(fmt.Sprintf("Case %s", tc.msg), func() {
+			suite.SetupTest() // reset
+
+			tc.malleate()
+			ctx := suite.ctx
+
+			res, err := suite.queryClient.DenomMetadataByQueryString(ctx, req)
+
+			if tc.expPass {
+				suite.Require().NoError(err)
+				suite.Require().NotNil(res)
+				suite.Require().Equal(expMetadata, res.Metadata)
+			} else {
+				suite.Require().Error(err)
+			}
+		})
+	}
+}
+
 func (suite *KeeperTestSuite) TestGRPCDenomOwners() {
 	ctx := suite.ctx