// WaitForStateChange blocks until the state changes to something other than the sourceState.
func (cc *Conn) WaitForStateChange(ctx context.Context, sourceState ConnectivityState) (ConnectivityState, error) {
cc.mu.Lock()
defer cc.mu.Unlock()
if sourceState != cc.state {
return cc.state, nil
}
done := make(chan struct{})
var err error
go func() {
select {
case <-ctx.Done():
cc.mu.Lock()
err = ctx.Err()
cc.stateCV.Broadcast()
cc.mu.Unlock()
case <-done:
}
}()
defer close(done)
for sourceState == cc.state {
cc.stateCV.Wait()
if err != nil {
return cc.state, err
}
}
return cc.state, nil
}
func (s *EtcdServer) processInternalRaftRequest(ctx context.Context, r pb.InternalRaftRequest) (*applyResult, error) {
r.ID = s.reqIDGen.Next()
data, err := r.Marshal()
if err != nil {
return nil, err
}
if len(data) > maxRequestBytes {
return nil, ErrRequestTooLarge
}
ch := s.w.Register(r.ID)
s.r.Propose(ctx, data)
select {
case x := <-ch:
return x.(*applyResult), nil
case <-ctx.Done():
s.w.Trigger(r.ID, nil) // GC wait
return nil, ctx.Err()
case <-s.done:
return nil, ErrStopped
}
}
// Wait blocks until i) the new transport is up or ii) ctx is done or iii) cc is closed.
func (cc *Conn) Wait(ctx context.Context) (transport.ClientTransport, error) {
for {
cc.mu.Lock()
switch {
case cc.state == Shutdown:
cc.mu.Unlock()
return nil, ErrClientConnClosing
case cc.state == Ready:
ct := cc.transport
cc.mu.Unlock()
return ct, nil
default:
ready := cc.ready
if ready == nil {
ready = make(chan struct{})
cc.ready = ready
}
cc.mu.Unlock()
select {
case <-ctx.Done():
return nil, transport.ContextErr(ctx.Err())
// Wait until the new transport is ready or failed.
case <-ready:
}
}
}
}
// When wait returns, either the new transport is up or ClientConn is
// closing. Used to avoid working on a dying transport. It updates and
// returns the transport and its version when there is no error.
func (cc *ClientConn) wait(ctx context.Context, ts int) (transport.ClientTransport, int, error) {
for {
cc.mu.Lock()
switch {
case cc.closing:
cc.mu.Unlock()
return nil, 0, ErrClientConnClosing
case ts < cc.transportSeq:
// Worked on a dying transport. Try the new one immediately.
defer cc.mu.Unlock()
return cc.transport, cc.transportSeq, nil
default:
ready := cc.ready
if ready == nil {
ready = make(chan struct{})
cc.ready = ready
}
cc.mu.Unlock()
select {
case <-ctx.Done():
return nil, 0, transport.ContextErr(ctx.Err())
// Wait until the new transport is ready or failed.
case <-ready:
}
}
}
}
// Do interprets r and performs an operation on s.store according to r.Method
// and other fields. If r.Method is "POST", "PUT", "DELETE", or a "GET" with
// Quorum == true, r will be sent through consensus before performing its
// respective operation. Do will block until an action is performed or there is
// an error.
func (s *EtcdServer) Do(ctx context.Context, r pb.Request) (Response, error) {
r.ID = s.reqIDGen.Next()
if r.Method == "GET" && r.Quorum {
r.Method = "QGET"
}
switch r.Method {
case "POST", "PUT", "DELETE", "QGET":
var raftReq pb.InternalRaftRequest
raftReq.V2 = &r
data, err := raftReq.Marshal()
if err != nil {
return Response{}, err
}
ch := s.w.Register(r.ID)
// TODO: benchmark the cost of time.Now()
// might be sampling?
start := time.Now()
s.r.Propose(ctx, data)
proposePending.Inc()
defer proposePending.Dec()
select {
case x := <-ch:
proposeDurations.Observe(float64(time.Since(start).Nanoseconds() / int64(time.Millisecond)))
resp := x.(Response)
return resp, resp.err
case <-ctx.Done():
proposeFailed.Inc()
s.w.Trigger(r.ID, nil) // GC wait
return Response{}, parseCtxErr(ctx.Err())
case <-s.done:
return Response{}, ErrStopped
}
case "GET":
switch {
case r.Wait:
wc, err := s.store.Watch(r.Path, r.Recursive, r.Stream, r.Since)
if err != nil {
return Response{}, err
}
return Response{Watcher: wc}, nil
default:
ev, err := s.store.Get(r.Path, r.Recursive, r.Sorted)
if err != nil {
return Response{}, err
}
return Response{Event: ev}, nil
}
case "HEAD":
ev, err := s.store.Get(r.Path, r.Recursive, r.Sorted)
if err != nil {
return Response{}, err
}
return Response{Event: ev}, nil
default:
return Response{}, ErrUnknownMethod
}
}
func (c *simpleHTTPClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
req := act.HTTPRequest(c.endpoint)
if err := printcURL(req); err != nil {
return nil, nil, err
}
rtchan := make(chan roundTripResponse, 1)
go func() {
resp, err := c.transport.RoundTrip(req)
rtchan <- roundTripResponse{resp: resp, err: err}
close(rtchan)
}()
var resp *http.Response
var err error
select {
case rtresp := <-rtchan:
resp, err = rtresp.resp, rtresp.err
case <-ctx.Done():
// cancel and wait for request to actually exit before continuing
c.transport.CancelRequest(req)
rtresp := <-rtchan
resp = rtresp.resp
err = ctx.Err()
}
// always check for resp nil-ness to deal with possible
// race conditions between channels above
defer func() {
if resp != nil {
resp.Body.Close()
}
}()
if err != nil {
return nil, nil, err
}
var body []byte
done := make(chan struct{})
go func() {
body, err = ioutil.ReadAll(resp.Body)
done <- struct{}{}
}()
select {
case <-ctx.Done():
err = resp.Body.Close()
<-done
if err == nil {
err = ctx.Err()
}
case <-done:
}
return resp, body, err
}
func waitUpdate(ctx context.Context, client *v3.Client, key string, opts ...v3.OpOption) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wresp, ok := <-client.Watch(cctx, key, opts...)
if !ok {
return ctx.Err()
}
return wresp.Err()
}
// wait blocks until it can receive from ctx.Done, closing, or proceed.
// If it receives from ctx.Done, it returns 0, the StreamError for ctx.Err.
// If it receives from closing, it returns 0, ErrConnClosing.
// If it receives from proceed, it returns the received integer, nil.
func wait(ctx context.Context, closing <-chan struct{}, proceed <-chan int) (int, error) {
select {
case <-ctx.Done():
return 0, ContextErr(ctx.Err())
case <-closing:
return 0, ErrConnClosing
case i := <-proceed:
return i, nil
}
}
// Do sends an HTTP request with the provided http.Client and returns an HTTP response.
// If the client is nil, http.DefaultClient is used.
// If the context is canceled or times out, ctx.Err() will be returned.
func Do(ctx context.Context, client *http.Client, req *http.Request) (*http.Response, error) {
if client == nil {
client = http.DefaultClient
}
// Request cancelation changed in Go 1.5, see cancelreq.go and cancelreq_go14.go.
cancel := canceler(client, req)
type responseAndError struct {
resp *http.Response
err error
}
result := make(chan responseAndError, 1)
go func() {
resp, err := client.Do(req)
testHookDoReturned()
result <- responseAndError{resp, err}
}()
var resp *http.Response
select {
case <-ctx.Done():
testHookContextDoneBeforeHeaders()
cancel()
// Clean up after the goroutine calling client.Do:
go func() {
if r := <-result; r.resp != nil {
testHookDidBodyClose()
r.resp.Body.Close()
}
}()
return nil, ctx.Err()
case r := <-result:
var err error
resp, err = r.resp, r.err
if err != nil {
return resp, err
}
}
c := make(chan struct{})
go func() {
select {
case <-ctx.Done():
cancel()
case <-c:
// The response's Body is closed.
}
}()
resp.Body = ¬ifyingReader{resp.Body, c}
return resp, nil
}
// Do interprets r and performs an operation on s.store according to r.Method
// and other fields. If r.Method is "POST", "PUT", "DELETE", or a "GET" with
// Quorum == true, r will be sent through consensus before performing its
// respective operation. Do will block until an action is performed or there is
// an error.
func (s *EtcdServer) Do(ctx context.Context, r pb.Request) (Response, error) {
if r.ID == 0 {
log.Panicf("request ID should never be 0")
}
if r.Method == "GET" && r.Quorum {
r.Method = "QGET"
}
switch r.Method {
case "POST", "PUT", "DELETE", "QGET":
data, err := r.Marshal()
if err != nil {
return Response{}, err
}
ch := s.w.Register(r.ID)
s.node.Propose(ctx, data)
select {
case x := <-ch:
resp := x.(Response)
return resp, resp.err
case <-ctx.Done():
s.w.Trigger(r.ID, nil) // GC wait
return Response{}, parseCtxErr(ctx.Err())
case <-s.done:
return Response{}, ErrStopped
}
case "GET":
switch {
case r.Wait:
wc, err := s.store.Watch(r.Path, r.Recursive, r.Stream, r.Since)
if err != nil {
return Response{}, err
}
return Response{Watcher: wc}, nil
default:
ev, err := s.store.Get(r.Path, r.Recursive, r.Sorted)
if err != nil {
return Response{}, err
}
return Response{Event: ev}, nil
}
case "HEAD":
ev, err := s.store.Get(r.Path, r.Recursive, r.Sorted)
if err != nil {
return Response{}, err
}
return Response{Event: ev}, nil
default:
return Response{}, ErrUnknownMethod
}
}
func (c *httpClusterClient) AutoSync(ctx context.Context, interval time.Duration) error {
ticker := time.NewTicker(interval)
defer ticker.Stop()
for {
err := c.Sync(ctx)
if err != nil {
return err
}
select {
case <-ctx.Done():
return ctx.Err()
case <-ticker.C:
}
}
}
// Step advances the state machine using msgs. The ctx.Err() will be returned,
// if any.
func (n *node) step(ctx context.Context, m pb.Message) error {
ch := n.recvc
if m.Type == pb.MsgProp {
ch = n.propc
}
select {
case ch <- m:
return nil
case <-ctx.Done():
return ctx.Err()
case <-n.done:
return ErrStopped
}
}
func (mn *multiNode) step(ctx context.Context, m multiMessage) error {
ch := mn.recvc
if m.msg.Type == pb.MsgProp {
ch = mn.propc
}
select {
case ch <- m:
return nil
case <-ctx.Done():
return ctx.Err()
case <-mn.done:
return ErrStopped
}
}
func waitDelete(ctx context.Context, client *v3.Client, key string, rev int64) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wch := client.Watch(cctx, key, v3.WithRev(rev))
for wr := range wch {
for _, ev := range wr.Events {
if ev.Type == storagepb.DELETE {
return nil
}
}
}
if err := ctx.Err(); err != nil {
return err
}
return fmt.Errorf("lost watcher waiting for delete")
}
func waitUpdate(ctx context.Context, client *v3.Client, key string, opts ...v3.OpOption) error {
w := v3.NewWatcher(client)
defer w.Close()
wc := w.Watch(ctx, key, opts...)
if wc == nil {
return ctx.Err()
}
wresp, ok := <-wc
if !ok {
return ctx.Err()
}
if len(wresp.Events) == 0 {
return v3rpc.ErrCompacted
}
return nil
}
// Step advances the state machine using msgs. The ctx.Err() will be returned,
// if any.
func (n *node) step(ctx context.Context, m pb.Message) error {
ch := n.recvc
if m.Type == pb.MsgProp {
ch = n.propc
}
select {
case ch <- m:
if m.Type == pb.MsgProp {
//NOTE: this case is accessed before quorum check
//plog.Infof("message is in channel")
}
return nil
case <-ctx.Done():
//plog.Infof("context is done, should not happen")
return ctx.Err()
case <-n.done:
//plog.Infof("node stopped")
return ErrStopped
}
}
// configure sends a configuration change through consensus and
// then waits for it to be applied to the server. It
// will block until the change is performed or there is an error.
func (s *EtcdServer) configure(ctx context.Context, cc raftpb.ConfChange) error {
ch := s.w.Register(cc.ID)
if err := s.node.ProposeConfChange(ctx, cc); err != nil {
s.w.Trigger(cc.ID, nil)
return err
}
select {
case x := <-ch:
if err, ok := x.(error); ok {
return err
}
if x != nil {
log.Panicf("return type should always be error")
}
return nil
case <-ctx.Done():
s.w.Trigger(cc.ID, nil) // GC wait
return parseCtxErr(ctx.Err())
case <-s.done:
return ErrStopped
}
}
func (s *EtcdServer) V3DemoDo(ctx context.Context, r pb.InternalRaftRequest) (proto.Message, error) {
r.ID = s.reqIDGen.Next()
data, err := r.Marshal()
if err != nil {
return &pb.EmptyResponse{}, err
}
ch := s.w.Register(r.ID)
s.r.Propose(ctx, data)
select {
case x := <-ch:
resp := x.(proto.Message)
return resp, nil
case <-ctx.Done():
s.w.Trigger(r.ID, nil) // GC wait
return &pb.EmptyResponse{}, ctx.Err()
case <-s.done:
return &pb.EmptyResponse{}, ErrStopped
}
}
func (c *httpClient) Do(ctx context.Context, act HTTPAction) (*http.Response, []byte, error) {
req := act.HTTPRequest(c.endpoint)
rtchan := make(chan roundTripResponse, 1)
go func() {
resp, err := c.transport.RoundTrip(req)
rtchan <- roundTripResponse{resp: resp, err: err}
close(rtchan)
}()
var resp *http.Response
var err error
select {
case rtresp := <-rtchan:
resp, err = rtresp.resp, rtresp.err
case <-ctx.Done():
c.transport.CancelRequest(req)
// wait for request to actually exit before continuing
<-rtchan
err = ctx.Err()
}
// always check for resp nil-ness to deal with possible
// race conditions between channels above
defer func() {
if resp != nil {
resp.Body.Close()
}
}()
if err != nil {
return nil, nil, err
}
body, err := ioutil.ReadAll(resp.Body)
return resp, body, err
}
func (c *simpleHTTPClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
req := act.HTTPRequest(c.endpoint)
if err := printcURL(req); err != nil {
return nil, nil, err
}
hctx, hcancel := context.WithCancel(ctx)
if c.headerTimeout > 0 {
hctx, hcancel = context.WithTimeout(ctx, c.headerTimeout)
}
defer hcancel()
rtchan := make(chan roundTripResponse, 1)
go func() {
resp, err := c.transport.RoundTrip(req)
rtchan <- roundTripResponse{resp: resp, err: err}
close(rtchan)
}()
var resp *http.Response
var err error
select {
case rtresp := <-rtchan:
resp, err = rtresp.resp, rtresp.err
case <-hctx.Done():
// cancel and wait for request to actually exit before continuing
c.transport.CancelRequest(req)
rtresp := <-rtchan
resp = rtresp.resp
switch {
case ctx.Err() != nil:
err = ctx.Err()
case hctx.Err() != nil:
err = fmt.Errorf("client: endpoint %s exceeded header timeout", c.endpoint.String())
default:
panic("failed to get error from context")
}
}
// always check for resp nil-ness to deal with possible
// race conditions between channels above
defer func() {
if resp != nil {
resp.Body.Close()
}
}()
if err != nil {
return nil, nil, err
}
var body []byte
done := make(chan struct{})
go func() {
body, err = ioutil.ReadAll(resp.Body)
done <- struct{}{}
}()
select {
case <-ctx.Done():
resp.Body.Close()
<-done
return nil, nil, ctx.Err()
case <-done:
}
return resp, body, err
}
// isHalted returns true if the given error and context indicate no forward
// progress can be made, even after reconnecting.
func isHalted(ctx context.Context, err error) bool {
isRPCError := strings.HasPrefix(grpc.ErrorDesc(err), "etcdserver: ")
return isRPCError || ctx.Err() != nil
}
func (c *simpleHTTPClient) Do(ctx context.Context, act httpAction) (*http.Response, []byte, error) {
req := act.HTTPRequest(c.endpoint)
if err := printcURL(req); err != nil {
return nil, nil, err
}
isWait := false
if req != nil && req.URL != nil {
ws := req.URL.Query().Get("wait")
if len(ws) != 0 {
var err error
isWait, err = strconv.ParseBool(ws)
if err != nil {
return nil, nil, fmt.Errorf("wrong wait value %s (%v for %+v)", ws, err, req)
}
}
}
var hctx context.Context
var hcancel context.CancelFunc
if !isWait && c.headerTimeout > 0 {
hctx, hcancel = context.WithTimeout(ctx, c.headerTimeout)
} else {
hctx, hcancel = context.WithCancel(ctx)
}
defer hcancel()
reqcancel := requestCanceler(c.transport, req)
rtchan := make(chan roundTripResponse, 1)
go func() {
resp, err := c.transport.RoundTrip(req)
rtchan <- roundTripResponse{resp: resp, err: err}
close(rtchan)
}()
var resp *http.Response
var err error
select {
case rtresp := <-rtchan:
resp, err = rtresp.resp, rtresp.err
case <-hctx.Done():
// cancel and wait for request to actually exit before continuing
reqcancel()
rtresp := <-rtchan
resp = rtresp.resp
switch {
case ctx.Err() != nil:
err = ctx.Err()
case hctx.Err() != nil:
err = fmt.Errorf("client: endpoint %s exceeded header timeout", c.endpoint.String())
default:
panic("failed to get error from context")
}
}
// always check for resp nil-ness to deal with possible
// race conditions between channels above
defer func() {
if resp != nil {
resp.Body.Close()
}
}()
if err != nil {
return nil, nil, err
}
var body []byte
done := make(chan struct{})
go func() {
body, err = ioutil.ReadAll(resp.Body)
done <- struct{}{}
}()
select {
case <-ctx.Done():
resp.Body.Close()
<-done
return nil, nil, ctx.Err()
case <-done:
}
return resp, body, err
}