Integrate gRPC queries into BaseApp (cosmos#6335)

* Rename GRPCRouter to GRPCQueryRouter, add to BaseApp

* Rename field

* add comment

* Update baseapp/abci.go

* Update baseapp/abci.go

Co-authored-by: Alexander Bezobchuk <[email protected]>

* Address review feedback

* Improve code reuse

* Fix errors

Co-authored-by: Federico Kunze <[email protected]>
Co-authored-by: Alexander Bezobchuk <[email protected]>

baseapp/abci.go

@@ -294,6 +294,12 @@ func (app *BaseApp) halt() {
 // Query implements the ABCI interface. It delegates to CommitMultiStore if it
 // implements Queryable.
 func (app *BaseApp) Query(req abci.RequestQuery) abci.ResponseQuery {
+	// handle gRPC routes first rather than calling splitPath because '/' characters
+	// are used as part of gRPC paths
+	if grpcHandler := app.grpcQueryRouter.Route(req.Path); grpcHandler != nil {
+		return app.handleQueryGRPC(grpcHandler, req)
+	}
+
 	path := splitPath(req.Path)
 	if len(path) == 0 {
 		sdkerrors.QueryResult(sdkerrors.Wrap(sdkerrors.ErrUnknownRequest, "no query path provided"))
@@ -317,6 +323,53 @@ func (app *BaseApp) Query(req abci.RequestQuery) abci.ResponseQuery {
 	return sdkerrors.QueryResult(sdkerrors.Wrap(sdkerrors.ErrUnknownRequest, "unknown query path"))
 }
 
+func (app *BaseApp) handleQueryGRPC(handler GRPCQueryHandler, req abci.RequestQuery) abci.ResponseQuery {
+	ctx, err := app.createQueryContext(req)
+	if err != nil {
+		return sdkerrors.QueryResult(err)
+	}
+
+	res, err := handler(ctx, req)
+	if err != nil {
+		res = sdkerrors.QueryResult(err)
+		res.Height = req.Height
+		return res
+	}
+
+	return res
+}
+
+func (app *BaseApp) createQueryContext(req abci.RequestQuery) (sdk.Context, error) {
+	// when a client did not provide a query height, manually inject the latest
+	if req.Height == 0 {
+		req.Height = app.LastBlockHeight()
+	}
+
+	if req.Height <= 1 && req.Prove {
+		return sdk.Context{},
+			sdkerrors.Wrap(
+				sdkerrors.ErrInvalidRequest,
+				"cannot query with proof when height <= 1; please provide a valid height",
+			)
+	}
+
+	cacheMS, err := app.cms.CacheMultiStoreWithVersion(req.Height)
+	if err != nil {
+		return sdk.Context{},
+			sdkerrors.Wrapf(
+				sdkerrors.ErrInvalidRequest,
+				"failed to load state at height %d; %s (latest height: %d)", req.Height, err, app.LastBlockHeight(),
+			)
+	}
+
+	// cache wrap the commit-multistore for safety
+	ctx := sdk.NewContext(
+		cacheMS, app.checkState.ctx.BlockHeader(), true, app.logger,
+	).WithMinGasPrices(app.minGasPrices)
+
+	return ctx, nil
+}
+
 func handleQueryApp(app *BaseApp, path []string, req abci.RequestQuery) abci.ResponseQuery {
 	if len(path) >= 2 {
 		switch path[1] {
@@ -439,48 +492,20 @@ func handleQueryCustom(app *BaseApp, path []string, req abci.RequestQuery) abci.
 		return sdkerrors.QueryResult(sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "no custom querier found for route %s", path[1]))
 	}
 
-	// when a client did not provide a query height, manually inject the latest
-	if req.Height == 0 {
-		req.Height = app.LastBlockHeight()
-	}
-
-	if req.Height <= 1 && req.Prove {
-		return sdkerrors.QueryResult(
-			sdkerrors.Wrap(
-				sdkerrors.ErrInvalidRequest,
-				"cannot query with proof when height <= 1; please provide a valid height",
-			),
-		)
-	}
-
-	cacheMS, err := app.cms.CacheMultiStoreWithVersion(req.Height)
+	ctx, err := app.createQueryContext(req)
 	if err != nil {
-		return sdkerrors.QueryResult(
-			sdkerrors.Wrapf(
-				sdkerrors.ErrInvalidRequest,
-				"failed to load state at height %d; %s (latest height: %d)", req.Height, err, app.LastBlockHeight(),
-			),
-		)
+		return sdkerrors.QueryResult(err)
 	}
 
-	// cache wrap the commit-multistore for safety
-	ctx := sdk.NewContext(
-		cacheMS, app.checkState.ctx.BlockHeader(), true, app.logger,
-	).WithMinGasPrices(app.minGasPrices)
-
 	// Passes the rest of the path as an argument to the querier.
 	//
 	// For example, in the path "custom/gov/proposal/test", the gov querier gets
 	// []string{"proposal", "test"} as the path.
 	resBytes, err := querier(ctx, path[2:], req)
 	if err != nil {
-		space, code, log := sdkerrors.ABCIInfo(err, false)
-		return abci.ResponseQuery{
-			Code:      code,
-			Codespace: space,
-			Log:       log,
-			Height:    req.Height,
-		}
+		res := sdkerrors.QueryResult(err)
+		res.Height = req.Height
+		return res
 	}
 
 	return abci.ResponseQuery{

baseapp/baseapp.go

@@ -6,6 +6,8 @@ import (
 	"runtime/debug"
 	"strings"
 
+	"github.com/gogo/protobuf/grpc"
+
 	abci "github.com/tendermint/tendermint/abci/types"
 	"github.com/tendermint/tendermint/crypto/tmhash"
 	"github.com/tendermint/tendermint/libs/log"
@@ -41,14 +43,15 @@ type (
 // BaseApp reflects the ABCI application implementation.
 type BaseApp struct { // nolint: maligned
 	// initialized on creation
-	logger      log.Logger
-	name        string               // application name from abci.Info
-	db          dbm.DB               // common DB backend
-	cms         sdk.CommitMultiStore // Main (uncached) state
-	storeLoader StoreLoader          // function to handle store loading, may be overridden with SetStoreLoader()
-	router      sdk.Router           // handle any kind of message
-	queryRouter sdk.QueryRouter      // router for redirecting query calls
-	txDecoder   sdk.TxDecoder        // unmarshal []byte into sdk.Tx
+	logger          log.Logger
+	name            string               // application name from abci.Info
+	db              dbm.DB               // common DB backend
+	cms             sdk.CommitMultiStore // Main (uncached) state
+	storeLoader     StoreLoader          // function to handle store loading, may be overridden with SetStoreLoader()
+	router          sdk.Router           // handle any kind of message
+	queryRouter     sdk.QueryRouter      // router for redirecting query calls
+	grpcQueryRouter *GRPCQueryRouter     // router for redirecting gRPC query calls
+	txDecoder       sdk.TxDecoder        // unmarshal []byte into sdk.Tx
 
 	anteHandler    sdk.AnteHandler  // ante handler for fee and auth
 	initChainer    sdk.InitChainer  // initialize state with validators and state blob
@@ -101,15 +104,16 @@ func NewBaseApp(
 	name string, logger log.Logger, db dbm.DB, txDecoder sdk.TxDecoder, options ...func(*BaseApp),
 ) *BaseApp {
 	app := &BaseApp{
-		logger:         logger,
-		name:           name,
-		db:             db,
-		cms:            store.NewCommitMultiStore(db),
-		storeLoader:    DefaultStoreLoader,
-		router:         NewRouter(),
-		queryRouter:    NewQueryRouter(),
-		txDecoder:      txDecoder,
-		fauxMerkleMode: false,
+		logger:          logger,
+		name:            name,
+		db:              db,
+		cms:             store.NewCommitMultiStore(db),
+		storeLoader:     DefaultStoreLoader,
+		router:          NewRouter(),
+		queryRouter:     NewQueryRouter(),
+		grpcQueryRouter: NewGRPCQueryRouter(),
+		txDecoder:       txDecoder,
+		fauxMerkleMode:  false,
 	}
 
 	for _, option := range options {
@@ -282,6 +286,9 @@ func (app *BaseApp) Router() sdk.Router {
 // QueryRouter returns the QueryRouter of a BaseApp.
 func (app *BaseApp) QueryRouter() sdk.QueryRouter { return app.queryRouter }
 
+// GRPCQueryRouter returns the GRPCQueryRouter of a BaseApp.
+func (app *BaseApp) GRPCQueryRouter() grpc.Server { return app.grpcQueryRouter }
+
 // Seal seals a BaseApp. It prohibits any further modifications to a BaseApp.
 func (app *BaseApp) Seal() { app.sealed = true }
 

baseapp/baseapp_test.go

@@ -10,6 +10,8 @@ import (
 	"sync"
 	"testing"
 
+	"github.com/cosmos/cosmos-sdk/codec/testdata"
+
 	"github.com/gogo/protobuf/jsonpb"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -1506,6 +1508,40 @@ func TestQuery(t *testing.T) {
 	require.Equal(t, value, res.Value)
 }
 
+func TestGRPCQuery(t *testing.T) {
+	grpcQueryOpt := func(bapp *BaseApp) {
+		testdata.RegisterTestServiceServer(
+			bapp.GRPCQueryRouter(),
+			testServer{},
+		)
+	}
+
+	app := setupBaseApp(t, grpcQueryOpt)
+
+	app.InitChain(abci.RequestInitChain{})
+	header := abci.Header{Height: app.LastBlockHeight() + 1}
+	app.BeginBlock(abci.RequestBeginBlock{Header: header})
+	app.Commit()
+
+	req := testdata.SayHelloRequest{Name: "foo"}
+	reqBz, err := req.Marshal()
+	require.NoError(t, err)
+
+	reqQuery := abci.RequestQuery{
+		Data: reqBz,
+		Path: "/cosmos_sdk.codec.v1.TestService/SayHello",
+	}
+
+	resQuery := app.Query(reqQuery)
+
+	require.Equal(t, abci.CodeTypeOK, resQuery.Code, resQuery)
+
+	var res testdata.SayHelloResponse
+	err = res.Unmarshal(resQuery.Value)
+	require.NoError(t, err)
+	require.Equal(t, "Hello foo!", res.Greeting)
+}
+
 // Test p2p filter queries
 func TestP2PQuery(t *testing.T) {
 	addrPeerFilterOpt := func(bapp *BaseApp) {

baseapp/grpcrouter.go

@@ -14,16 +14,16 @@ import (
 
 var protoCodec = encoding.GetCodec(proto.Name)
 
-// GRPCRouter routes ABCI Query requests to GRPC handlers
-type GRPCRouter struct {
+// GRPCQueryRouter routes ABCI Query requests to GRPC handlers
+type GRPCQueryRouter struct {
 	routes map[string]GRPCQueryHandler
 }
 
 var _ gogogrpc.Server
 
-// NewGRPCRouter creates a new GRPCRouter
-func NewGRPCRouter() *GRPCRouter {
-	return &GRPCRouter{
+// NewGRPCQueryRouter creates a new GRPCQueryRouter
+func NewGRPCQueryRouter() *GRPCQueryRouter {
+	return &GRPCQueryRouter{
 		routes: map[string]GRPCQueryHandler{},
 	}
 }
@@ -34,7 +34,7 @@ type GRPCQueryHandler = func(ctx sdk.Context, req abci.RequestQuery) (abci.Respo
 
 // Route returns the GRPCQueryHandler for a given query route path or nil
 // if not found
-func (qrt *GRPCRouter) Route(path string) GRPCQueryHandler {
+func (qrt *GRPCQueryRouter) Route(path string) GRPCQueryHandler {
 	handler, found := qrt.routes[path]
 	if !found {
 		return nil
@@ -44,7 +44,7 @@ func (qrt *GRPCRouter) Route(path string) GRPCQueryHandler {
 
 // RegisterService implements the gRPC Server.RegisterService method. sd is a gRPC
 // service description, handler is an object which implements that gRPC service
-func (qrt *GRPCRouter) RegisterService(sd *grpc.ServiceDesc, handler interface{}) {
+func (qrt *GRPCQueryRouter) RegisterService(sd *grpc.ServiceDesc, handler interface{}) {
 	// adds a top-level query handler based on the gRPC service name
 	for _, method := range sd.Methods {
 		fqName := fmt.Sprintf("/%s/%s", sd.ServiceName, method.MethodName)

baseapp/grpcrouter_helpers.go

@@ -16,14 +16,14 @@ import (
 // interfaces needed to register a query service server and create a query
 // service client.
 type QueryServiceTestHelper struct {
-	*GRPCRouter
+	*GRPCQueryRouter
 	ctx sdk.Context
 }
 
 // NewQueryServerTestHelper creates a new QueryServiceTestHelper that wraps
 // the provided sdk.Context
 func NewQueryServerTestHelper(ctx sdk.Context) *QueryServiceTestHelper {
-	return &QueryServiceTestHelper{GRPCRouter: NewGRPCRouter(), ctx: ctx}
+	return &QueryServiceTestHelper{GRPCQueryRouter: NewGRPCQueryRouter(), ctx: ctx}
 }
 
 // Invoke implements the grpc ClientConn.Invoke method

baseapp/grpcrouter_test.go

@@ -25,11 +25,11 @@ func (e testServer) SayHello(_ context.Context, request *testdata.SayHelloReques
 var _ testdata.TestServiceServer = testServer{}
 
 func TestGRPCRouter(t *testing.T) {
-	qr := NewGRPCRouter()
+	qr := NewGRPCQueryRouter()
 	testdata.RegisterTestServiceServer(qr, testServer{})
 	helper := &QueryServiceTestHelper{
-		GRPCRouter: qr,
-		ctx:        sdk.Context{},
+		GRPCQueryRouter: qr,
+		ctx:             sdk.Context{},
 	}
 	client := testdata.NewTestServiceClient(helper)