// publish registers server information into the cluster. The information
// is the JSON representation of this server's member struct, updated with the
// static clientURLs of the server.
// The function keeps attempting to register until it succeeds,
// or its server is stopped.
func (s *EtcdServer) publish(retryInterval time.Duration) {
b, err := json.Marshal(s.attributes)
if err != nil {
log.Printf("etcdserver: json marshal error: %v", err)
return
}
req := pb.Request{
ID: GenID(),
Method: "PUT",
Path: path.Join(memberStoreKey(s.id), attributesSuffix),
Val: string(b),
}
for {
ctx, cancel := context.WithTimeout(context.Background(), retryInterval)
_, err := s.Do(ctx, req)
cancel()
switch err {
case nil:
log.Printf("etcdserver: published %+v to cluster %x", s.attributes, s.Cluster.ID())
return
case ErrStopped:
log.Printf("etcdserver: aborting publish because server is stopped")
return
default:
log.Printf("etcdserver: publish error: %v", err)
}
}
}
func ExampleWithTimeout() {
// Pass a context with a timeout to tell a blocking function that it
// should abandon its work after the timeout elapses.
ctx, _ := context.WithTimeout(context.Background(), 100*time.Millisecond)
select {
case <-time.After(200 * time.Millisecond):
fmt.Println("overslept")
case <-ctx.Done():
fmt.Println(ctx.Err()) // prints "context deadline exceeded"
}
// Output:
// context deadline exceeded
}
func (h *keysHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if !allowMethod(w, r.Method, "GET", "PUT", "POST", "DELETE") {
return
}
cid := strconv.FormatUint(h.clusterInfo.ID(), 16)
w.Header().Set("X-Etcd-Cluster-ID", cid)
ctx, cancel := context.WithTimeout(context.Background(), h.timeout)
defer cancel()
rr, err := parseKeyRequest(r, etcdserver.GenID(), clockwork.NewRealClock())
if err != nil {
writeError(w, err)
return
}
resp, err := h.server.Do(ctx, rr)
if err != nil {
err = trimErrorPrefix(err, etcdserver.StoreKeysPrefix)
writeError(w, err)
return
}
switch {
case resp.Event != nil:
if err := writeKeyEvent(w, resp.Event, h.timer); err != nil {
// Should never be reached
log.Printf("error writing event: %v", err)
}
case resp.Watcher != nil:
ctx, cancel := context.WithTimeout(context.Background(), defaultWatchTimeout)
defer cancel()
handleKeyWatch(ctx, w, resp.Watcher, rr.Stream, h.timer)
default:
writeError(w, errors.New("received response with no Event/Watcher!"))
}
}
// sync proposes a SYNC request and is non-blocking.
// This makes no guarantee that the request will be proposed or performed.
// The request will be cancelled after the given timeout.
func (s *EtcdServer) sync(timeout time.Duration) {
ctx, cancel := context.WithTimeout(context.Background(), timeout)
req := pb.Request{
Method: "SYNC",
ID: GenID(),
Time: time.Now().UnixNano(),
}
data := pbutil.MustMarshal(&req)
// There is no promise that node has leader when do SYNC request,
// so it uses goroutine to propose.
go func() {
s.node.Propose(ctx, data)
cancel()
}()
}
func (c *httpClient) doWithTimeout(act httpAction) (*http.Response, []byte, error) {
ctx, cancel := context.WithTimeout(context.Background(), c.timeout)
defer cancel()
return c.do(ctx, act)
}
func (h *adminMembersHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if !allowMethod(w, r.Method, "GET", "POST", "DELETE") {
return
}
cid := strconv.FormatUint(h.clusterInfo.ID(), 16)
w.Header().Set("X-Etcd-Cluster-ID", cid)
ctx, cancel := context.WithTimeout(context.Background(), defaultServerTimeout)
defer cancel()
switch r.Method {
case "GET":
if trimPrefix(r.URL.Path, adminMembersPrefix) != "" {
writeError(w, httptypes.NewHTTPError(http.StatusNotFound, "Not found"))
return
}
mc := newMemberCollection(h.clusterInfo.Members())
w.Header().Set("Content-Type", "application/json")
if err := json.NewEncoder(w).Encode(mc); err != nil {
log.Printf("etcdhttp: %v", err)
}
case "POST":
ctype := r.Header.Get("Content-Type")
if ctype != "application/json" {
writeError(w, httptypes.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Bad Content-Type %s, accept application/json", ctype)))
return
}
b, err := ioutil.ReadAll(r.Body)
if err != nil {
writeError(w, httptypes.NewHTTPError(http.StatusBadRequest, err.Error()))
return
}
raftAttr := etcdserver.RaftAttributes{}
if err := json.Unmarshal(b, &raftAttr); err != nil {
writeError(w, httptypes.NewHTTPError(http.StatusBadRequest, err.Error()))
return
}
validURLs, err := types.NewURLs(raftAttr.PeerURLs)
if err != nil {
writeError(w, httptypes.NewHTTPError(http.StatusBadRequest, "Bad peer urls"))
return
}
now := h.clock.Now()
m := etcdserver.NewMember("", validURLs, "", &now)
if err := h.server.AddMember(ctx, *m); err != nil {
log.Printf("etcdhttp: error adding node %x: %v", m.ID, err)
writeError(w, err)
return
}
log.Printf("etcdhttp: added node %x with peer urls %v", m.ID, raftAttr.PeerURLs)
w.Header().Set("Content-Type", "application/json")
w.WriteHeader(http.StatusCreated)
if err := json.NewEncoder(w).Encode(m); err != nil {
log.Printf("etcdhttp: %v", err)
}
case "DELETE":
idStr := trimPrefix(r.URL.Path, adminMembersPrefix)
if idStr == "" {
http.Error(w, "Method Not Allowed", http.StatusMethodNotAllowed)
return
}
id, err := strconv.ParseUint(idStr, 16, 64)
if err != nil {
writeError(w, httptypes.NewHTTPError(http.StatusBadRequest, err.Error()))
return
}
log.Printf("etcdhttp: remove node %x", id)
if err := h.server.RemoveMember(ctx, id); err != nil {
log.Printf("etcdhttp: error removing node %x: %v", id, err)
writeError(w, err)
return
}
w.WriteHeader(http.StatusNoContent)
}
}