test(abciclient): add parallel grpc execution test (#758)

* test(abciclient): add grpc client test

* chore: typo

abci/client/client.go

@@ -69,9 +69,9 @@ func makeReqRes(ctx context.Context, req *types.Request) *requestAndResponse {
 }
 
 // markDone marks the ReqRes object as done.
-func (r *requestAndResponse) markDone() {
-	r.mtx.Lock()
-	defer r.mtx.Unlock()
+func (reqResp *requestAndResponse) markDone() {
+	reqResp.mtx.Lock()
+	defer reqResp.mtx.Unlock()
 
-	close(r.signal)
+	close(reqResp.signal)
 }

abci/client/grpc_client_test.go

@@ -0,0 +1,114 @@
+package abciclient_test
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/fortytw2/leaktest"
+
+	abciclient "github.com/dashpay/tenderdash/abci/client"
+	abciserver "github.com/dashpay/tenderdash/abci/server"
+	"github.com/dashpay/tenderdash/abci/types"
+	"github.com/dashpay/tenderdash/libs/log"
+	"github.com/dashpay/tenderdash/libs/service"
+)
+
+// TestGRPCClientServerParallel tests that gRPC client and server can handle multiple parallel requests
+func TestGRPCClientServerParallel(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+	defer cancel()
+
+	logger := log.NewNopLogger()
+	app := &mockApplication{t: t}
+
+	socket := t.TempDir() + "/grpc_test"
+	client, _, err := makeGRPCClientServer(ctx, t, logger, app, socket)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// we'll use that mutex to ensure threads don't finish before we check status
+	app.mtx.Lock()
+
+	const threads = 5
+	// started will be marked as done as soon as app.Info() handler executes on the server
+	app.started.Add(threads)
+	// done will be used to wait for all threads to finish
+	var done sync.WaitGroup
+	done.Add(threads)
+
+	for i := 0; i < threads; i++ {
+		thread := uint64(i)
+		go func() {
+			_, _ = client.Info(ctx, &types.RequestInfo{BlockVersion: thread})
+			done.Done()
+		}()
+	}
+
+	// wait for threads to execute
+	// note it doesn't mean threads are really done, as they are waiting on the mtx
+	// so if all `started` are marked as done, it means all threads have started
+	// in parallel
+	app.started.Wait()
+
+	// unlock the mutex so that threads can finish their execution
+	app.mtx.Unlock()
+
+	// wait for all threads to really finish
+	done.Wait()
+}
+
+func makeGRPCClientServer(
+	ctx context.Context,
+	t *testing.T,
+	logger log.Logger,
+	app types.Application,
+	name string,
+) (abciclient.Client, service.Service, error) {
+	ctx, cancel := context.WithCancel(ctx)
+	t.Cleanup(cancel)
+	t.Cleanup(leaktest.Check(t))
+
+	// Start the listener
+	socket := fmt.Sprintf("unix://%s.sock", name)
+
+	server := abciserver.NewGRPCServer(logger.With("module", "abci-server"), socket, app)
+
+	if err := server.Start(ctx); err != nil {
+		cancel()
+		return nil, nil, err
+	}
+
+	client := abciclient.NewGRPCClient(logger.With("module", "abci-client"), socket, true)
+
+	if err := client.Start(ctx); err != nil {
+		cancel()
+		return nil, nil, err
+	}
+	return client, server, nil
+}
+
+// mockApplication that will decrease mockApplication.started when called Info, and then wait until
+// mtx is unlocked before it finishes
+type mockApplication struct {
+	types.BaseApplication
+	mtx sync.Mutex
+	// we'll use that to ensure all threads have started
+	started sync.WaitGroup
+
+	t *testing.T
+}
+
+func (m *mockApplication) Info(_ctx context.Context, req *types.RequestInfo) (res *types.ResponseInfo, err error) {
+	m.t.Logf("Info %d called", req.BlockVersion)
+	// mark wg as done to signal that we have executed
+	m.started.Done()
+	// we will wait here until all threads mark wg as done
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+	m.t.Logf("Info %d finished", req.BlockVersion)
+	return &types.ResponseInfo{}, nil
+}

abci/client/routed_client_test.go

@@ -128,7 +128,6 @@ func TestRoutedClientGrpc(t *testing.T) {
 
 	logger := log.NewTestingLogger(t)
 
-	// app := types.NewBaseApplication()
 	app := mocks.NewApplication(t)
 	defer app.AssertExpectations(t)
 	app.On("Echo", mock.Anything, mock.Anything).Return(