package rpcclient import ( "context" "encoding/json" "net" "net/http" "net/http/httptest" "sync" "testing" "time" "github.com/gorilla/websocket" "github.com/stretchr/testify/require" "github.com/tendermint/tmlibs/log" types "github.com/tendermint/tendermint/rpc/lib/types" ) var wsCallTimeout = 5 * time.Second type myHandler struct { closeConnAfterRead bool mtx sync.RWMutex } var upgrader = websocket.Upgrader{ ReadBufferSize: 1024, WriteBufferSize: 1024, } func (h *myHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { conn, err := upgrader.Upgrade(w, r, nil) if err != nil { panic(err) } defer conn.Close() // nolint: errcheck for { messageType, _, err := conn.ReadMessage() if err != nil { return } h.mtx.RLock() if h.closeConnAfterRead { if err := conn.Close(); err != nil { panic(err) } } h.mtx.RUnlock() res := json.RawMessage(`{}`) emptyRespBytes, _ := json.Marshal(types.RPCResponse{Result: res}) if err := conn.WriteMessage(messageType, emptyRespBytes); err != nil { return } } } func TestWSClientReconnectsAfterReadFailure(t *testing.T) { var wg sync.WaitGroup // start server h := &myHandler{} s := httptest.NewServer(h) defer s.Close() c := startClient(t, s.Listener.Addr()) defer c.Stop() wg.Add(1) go callWgDoneOnResult(t, c, &wg) h.mtx.Lock() h.closeConnAfterRead = true h.mtx.Unlock() // results in WS read error, no send retry because write succeeded call(t, "a", c) // expect to reconnect almost immediately time.Sleep(10 * time.Millisecond) h.mtx.Lock() h.closeConnAfterRead = false h.mtx.Unlock() // should succeed call(t, "b", c) wg.Wait() } func TestWSClientReconnectsAfterWriteFailure(t *testing.T) { var wg sync.WaitGroup // start server h := &myHandler{} s := httptest.NewServer(h) c := startClient(t, s.Listener.Addr()) defer c.Stop() wg.Add(2) go callWgDoneOnResult(t, c, &wg) // hacky way to abort the connection before write if err := c.conn.Close(); err != nil { t.Error(err) } // results in WS write error, the client should resend on reconnect call(t, "a", c) // expect to reconnect almost immediately time.Sleep(10 * time.Millisecond) // should succeed call(t, "b", c) wg.Wait() } func TestWSClientReconnectFailure(t *testing.T) { // start server h := &myHandler{} s := httptest.NewServer(h) c := startClient(t, s.Listener.Addr()) defer c.Stop() go func() { for { select { case <-c.ResponsesCh: case <-c.Quit: return } } }() // hacky way to abort the connection before write if err := c.conn.Close(); err != nil { t.Error(err) } s.Close() // results in WS write error // provide timeout to avoid blocking ctx, cancel := context.WithTimeout(context.Background(), wsCallTimeout) defer cancel() if err := c.Call(ctx, "a", make(map[string]interface{})); err != nil { t.Error(err) } // expect to reconnect almost immediately time.Sleep(10 * time.Millisecond) done := make(chan struct{}) go func() { // client should block on this call(t, "b", c) close(done) }() // test that client blocks on the second send select { case <-done: t.Fatal("client should block on calling 'b' during reconnect") case <-time.After(5 * time.Second): t.Log("All good") } } func TestNotBlockingOnStop(t *testing.T) { timeout := 2 * time.Second s := httptest.NewServer(&myHandler{}) c := startClient(t, s.Listener.Addr()) c.Call(context.Background(), "a", make(map[string]interface{})) // Let the readRoutine get around to blocking time.Sleep(time.Second) passCh := make(chan struct{}) go func() { // Unless we have a non-blocking write to ResponsesCh from readRoutine // this blocks forever ont the waitgroup c.Stop() passCh <- struct{}{} }() select { case <-passCh: // Pass case <-time.After(timeout): t.Fatalf("WSClient did failed to stop within %v seconds - is one of the read/write routines blocking?", timeout.Seconds()) } } func startClient(t *testing.T, addr net.Addr) *WSClient { c := NewWSClient(addr.String(), "/websocket") err := c.Start() require.Nil(t, err) c.SetLogger(log.TestingLogger()) return c } func call(t *testing.T, method string, c *WSClient) { err := c.Call(context.Background(), method, make(map[string]interface{})) require.NoError(t, err) } func callWgDoneOnResult(t *testing.T, c *WSClient, wg *sync.WaitGroup) { for { select { case resp := <-c.ResponsesCh: if resp.Error != nil { t.Fatalf("unexpected error: %v", resp.Error) } if resp.Result != nil { wg.Done() } case <-c.Quit: return } } }