etcd/rafthttp/http.go

194 lines
5.0 KiB
Go

// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package rafthttp
import (
"io/ioutil"
"log"
"net/http"
"path"
"github.com/coreos/etcd/Godeps/_workspace/src/golang.org/x/net/context"
pioutil "github.com/coreos/etcd/pkg/ioutil"
"github.com/coreos/etcd/pkg/types"
"github.com/coreos/etcd/raft/raftpb"
)
const (
ConnReadLimitByte = 64 * 1024
)
var (
RaftPrefix = "/raft"
RaftStreamPrefix = path.Join(RaftPrefix, "stream")
)
func NewHandler(r Raft, cid types.ID) http.Handler {
return &handler{
r: r,
cid: cid,
}
}
func newStreamHandler(tr *transport, id, cid types.ID) http.Handler {
return &streamHandler{
tr: tr,
id: id,
cid: cid,
}
}
type writerToResponse interface {
WriteTo(w http.ResponseWriter)
}
type handler struct {
r Raft
cid types.ID
}
func (h *handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if r.Method != "POST" {
w.Header().Set("Allow", "POST")
http.Error(w, "Method Not Allowed", http.StatusMethodNotAllowed)
return
}
wcid := h.cid.String()
w.Header().Set("X-Etcd-Cluster-ID", wcid)
gcid := r.Header.Get("X-Etcd-Cluster-ID")
if gcid != wcid {
log.Printf("rafthttp: request ignored due to cluster ID mismatch got %s want %s", gcid, wcid)
http.Error(w, "clusterID mismatch", http.StatusPreconditionFailed)
return
}
// Limit the data size that could be read from the request body, which ensures that read from
// connection will not time out accidentally due to possible block in underlying implementation.
limitedr := pioutil.NewLimitedBufferReader(r.Body, ConnReadLimitByte)
b, err := ioutil.ReadAll(limitedr)
if err != nil {
log.Println("rafthttp: error reading raft message:", err)
http.Error(w, "error reading raft message", http.StatusBadRequest)
return
}
var m raftpb.Message
if err := m.Unmarshal(b); err != nil {
log.Println("rafthttp: error unmarshaling raft message:", err)
http.Error(w, "error unmarshaling raft message", http.StatusBadRequest)
return
}
if err := h.r.Process(context.TODO(), m); err != nil {
switch v := err.(type) {
case writerToResponse:
v.WriteTo(w)
default:
log.Printf("rafthttp: error processing raft message: %v", err)
http.Error(w, "error processing raft message", http.StatusInternalServerError)
}
return
}
w.WriteHeader(http.StatusNoContent)
}
type streamHandler struct {
tr *transport
id types.ID
cid types.ID
}
func (h *streamHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if r.Method != "GET" {
w.Header().Set("Allow", "GET")
http.Error(w, "Method Not Allowed", http.StatusMethodNotAllowed)
return
}
var t streamType
switch path.Dir(r.URL.Path) {
case path.Join(RaftStreamPrefix, string(streamTypeMsgApp)):
t = streamTypeMsgApp
case path.Join(RaftStreamPrefix, string(streamTypeMessage)):
t = streamTypeMessage
// backward compatibility
case RaftStreamPrefix:
t = streamTypeMsgApp
default:
log.Printf("rafthttp: ignored unexpected streaming request path %s", r.URL.Path)
http.Error(w, "invalid path", http.StatusNotFound)
return
}
fromStr := path.Base(r.URL.Path)
from, err := types.IDFromString(fromStr)
if err != nil {
log.Printf("rafthttp: failed to parse from %s into ID", fromStr)
http.Error(w, "invalid from", http.StatusNotFound)
return
}
p := h.tr.Peer(from)
if p == nil {
log.Printf("rafthttp: fail to find sender %s", from)
http.Error(w, "error sender not found", http.StatusNotFound)
return
}
wcid := h.cid.String()
if gcid := r.Header.Get("X-Etcd-Cluster-ID"); gcid != wcid {
log.Printf("rafthttp: streaming request ignored due to cluster ID mismatch got %s want %s", gcid, wcid)
http.Error(w, "clusterID mismatch", http.StatusPreconditionFailed)
return
}
wto := h.id.String()
if gto := r.Header.Get("X-Raft-To"); gto != wto {
log.Printf("rafthttp: streaming request ignored due to ID mismatch got %s want %s", gto, wto)
http.Error(w, "to field mismatch", http.StatusPreconditionFailed)
return
}
w.WriteHeader(http.StatusOK)
w.(http.Flusher).Flush()
c := newCloseNotifier()
conn := &outgoingConn{
t: t,
termStr: r.Header.Get("X-Raft-Term"),
Writer: w,
Flusher: w.(http.Flusher),
Closer: c,
}
p.attachOutgoingConn(conn)
<-c.closeNotify()
}
type closeNotifier struct {
done chan struct{}
}
func newCloseNotifier() *closeNotifier {
return &closeNotifier{
done: make(chan struct{}),
}
}
func (n *closeNotifier) Close() error {
close(n.done)
return nil
}
func (n *closeNotifier) closeNotify() <-chan struct{} { return n.done }