Make client.Context implement gRPC ClientConn (#6342)

* Add QueryConn to client.Context

* Add integration test

* imports

* spelling

* Make client.Context implement grpc ClientConn

Co-authored-by: Alexander Bezobchuk <alexanderbez@users.noreply.github.com>
Co-authored-by: Federico Kunze <31522760+fedekunze@users.noreply.github.com>

baseapp/baseapp_test.go

@@ -1555,7 +1555,7 @@ func TestGRPCQuery(t *testing.T) {
 	grpcQueryOpt := func(bapp *BaseApp) {
 		testdata.RegisterTestServiceServer(
 			bapp.GRPCQueryRouter(),
-			testServer{},
+			testdata.TestServiceImpl{},
 		)
 	}
 

baseapp/grpcrouter_test.go

@@ -2,7 +2,6 @@ package baseapp
 
 import (
 	"context"
-	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/require"
@@ -11,22 +10,9 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
-type testServer struct{}
-
-func (e testServer) Echo(_ context.Context, req *testdata.EchoRequest) (*testdata.EchoResponse, error) {
-	return &testdata.EchoResponse{Message: req.Message}, nil
-}
-
-func (e testServer) SayHello(_ context.Context, request *testdata.SayHelloRequest) (*testdata.SayHelloResponse, error) {
-	greeting := fmt.Sprintf("Hello %s!", request.Name)
-	return &testdata.SayHelloResponse{Greeting: greeting}, nil
-}
-
-var _ testdata.TestServiceServer = testServer{}
-
 func TestGRPCRouter(t *testing.T) {
 	qr := NewGRPCQueryRouter()
-	testdata.RegisterTestServiceServer(qr, testServer{})
+	testdata.RegisterTestServiceServer(qr, testdata.TestServiceImpl{})
 	helper := &QueryServiceTestHelper{
 		GRPCQueryRouter: qr,
 		ctx:             sdk.Context{},

client/grpc_query.go

@@ -0,0 +1,33 @@
+package client
+
+import (
+	gocontext "context"
+	"fmt"
+
+	gogogrpc "github.com/gogo/protobuf/grpc"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/encoding"
+	"google.golang.org/grpc/encoding/proto"
+)
+
+var _ gogogrpc.ClientConn = Context{}
+
+var protoCodec = encoding.GetCodec(proto.Name)
+
+// Invoke implements the grpc ClientConn.Invoke method
+func (ctx Context) Invoke(_ gocontext.Context, method string, args, reply interface{}, _ ...grpc.CallOption) error {
+	reqBz, err := protoCodec.Marshal(args)
+	if err != nil {
+		return err
+	}
+	resBz, _, err := ctx.QueryWithData(method, reqBz)
+	if err != nil {
+		return err
+	}
+	return protoCodec.Unmarshal(resBz, reply)
+}
+
+// NewStream implements the grpc ClientConn.NewStream method
+func (Context) NewStream(gocontext.Context, *grpc.StreamDesc, string, ...grpc.CallOption) (grpc.ClientStream, error) {
+	return nil, fmt.Errorf("streaming rpc not supported")
+}

codec/testdata/test_service.go

@@ -0,0 +1,19 @@
+package testdata
+
+import (
+	"context"
+	"fmt"
+)
+
+type TestServiceImpl struct{}
+
+func (e TestServiceImpl) Echo(_ context.Context, req *EchoRequest) (*EchoResponse, error) {
+	return &EchoResponse{Message: req.Message}, nil
+}
+
+func (e TestServiceImpl) SayHello(_ context.Context, request *SayHelloRequest) (*SayHelloResponse, error) {
+	greeting := fmt.Sprintf("Hello %s!", request.Name)
+	return &SayHelloResponse{Greeting: greeting}, nil
+}
+
+var _ TestServiceServer = TestServiceImpl{}

simapp/app.go

@@ -4,8 +4,6 @@ import (
 	"io"
 	"os"
 
-	"github.com/cosmos/cosmos-sdk/codec/types"
-
 	abci "github.com/tendermint/tendermint/abci/types"
 	"github.com/tendermint/tendermint/libs/log"
 	tmos "github.com/tendermint/tendermint/libs/os"
@@ -13,6 +11,8 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
+	"github.com/cosmos/cosmos-sdk/codec/testdata"
+	"github.com/cosmos/cosmos-sdk/codec/types"
 	"github.com/cosmos/cosmos-sdk/std"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/module"
@@ -306,6 +306,9 @@ func NewSimApp(
 	app.mm.RegisterRoutes(app.Router(), app.QueryRouter())
 	app.mm.RegisterQueryServices(app.GRPCQueryRouter())
 
+	// add test gRPC service for testing gRPC queries in isolation
+	testdata.RegisterTestServiceServer(app.GRPCQueryRouter(), testdata.TestServiceImpl{})
+
 	// create the simulation manager and define the order of the modules for deterministic simulations
 	//
 	// NOTE: this is not required apps that don't use the simulator for fuzz testing

tests/cli/grpc_query_test.go

@@ -0,0 +1,28 @@
+// +build cli_test
+
+package cli
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/codec/testdata"
+)
+
+func TestCliQueryConn(t *testing.T) {
+	t.Parallel()
+	f := NewFixtures(t)
+
+	// start simd server
+	proc := f.SDStart()
+	t.Cleanup(func() { proc.Stop(false) })
+
+	ctx := client.NewContext()
+	testClient := testdata.NewTestServiceClient(ctx)
+	res, err := testClient.Echo(context.Background(), &testdata.EchoRequest{Message: "hello"})
+	require.NoError(t, err)
+	require.Equal(t, "hello", res.Message)
+}