zolfa
/
tendermint


								package rpcclient


								import (

									"context"

									"encoding/json"

									"net/http"

									"net/http/httptest"

									"sync"

									"testing"

									"time"


									"github.com/gorilla/websocket"

									"github.com/stretchr/testify/require"

									"github.com/tendermint/tendermint/libs/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().String())

									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().String())

									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().String())

									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().String())

									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 string) *WSClient {

									c := NewWSClient(addr, "/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.Errorf("unexpected error: %v", resp.Error)

												return

											}

											if resp.Result != nil {

												wg.Done()

											}

										case <-c.Quit():

											return

										}

									}

								}