gateway: open timeout function cabinet (#3047)

Co-authored-by: Kevin Wan <wanjunfeng@gmail.com>

internal/mock/depositserver.go

@@ -0,0 +1,22 @@
+package mock
+
+import (
+	"context"
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// DepositServer is used for mocking.
+type DepositServer struct{}
+
+// Deposit handles the deposit requests.
+func (*DepositServer) Deposit(ctx context.Context, req *DepositRequest) (*DepositResponse, error) {
+	if req.GetAmount() < 0 {
+		return nil, status.Errorf(codes.InvalidArgument, "cannot deposit %v", req.GetAmount())
+	}
+
+	time.Sleep(time.Duration(req.GetAmount()) * time.Millisecond)
+	return &DepositResponse{Ok: true}, nil
+}