Rainbond/discover/discover.go
2020-11-25 16:39:38 +08:00

316 lines
7.8 KiB
Go

// Copyright (C) 2014-2018 Goodrain Co., Ltd.
// RAINBOND, Application Management Platform
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version. For any non-GPL usage of Rainbond,
// one or multiple Commercial Licenses authorized by Goodrain Co., Ltd.
// must be obtained first.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package discover
import (
"fmt"
"strconv"
"strings"
"sync"
"time"
"github.com/goodrain/rainbond/util/watch"
"github.com/goodrain/rainbond/discover/config"
"golang.org/x/net/context"
"github.com/coreos/etcd/mvcc/mvccpb"
etcdutil "github.com/goodrain/rainbond/util/etcd"
"github.com/sirupsen/logrus"
)
//CallbackUpdate 每次返还变化
type CallbackUpdate interface {
//TODO:
//weight自动发现更改实现暂时不 Ready
UpdateEndpoints(operation config.Operation, endpoints ...*config.Endpoint)
//when watch occurred error,will exec this method
Error(error)
}
//Callback 每次返回全部节点
type Callback interface {
UpdateEndpoints(endpoints ...*config.Endpoint)
//when watch occurred error,will exec this method
Error(error)
}
//Discover 后端服务自动发现
type Discover interface {
AddProject(name string, callback Callback)
AddUpdateProject(name string, callback CallbackUpdate)
Stop()
}
//GetDiscover 获取服务发现管理器
func GetDiscover(opt config.DiscoverConfig) (Discover, error) {
if opt.Ctx == nil {
opt.Ctx = context.Background()
}
ctx, cancel := context.WithCancel(opt.Ctx)
client, err := etcdutil.NewClient(ctx, opt.EtcdClientArgs)
if err != nil {
cancel()
return nil, err
}
watcher := watch.New(client, "")
etcdD := &etcdDiscover{
projects: make(map[string]CallbackUpdate),
ctx: ctx,
cancel: cancel,
watcher: watcher,
prefix: "/traefik",
}
return etcdD, nil
}
type etcdDiscover struct {
projects map[string]CallbackUpdate
lock sync.Mutex
ctx context.Context
cancel context.CancelFunc
watcher watch.Watch
prefix string
}
type defaultCallBackUpdate struct {
endpoints map[string]*config.Endpoint
callback Callback
lock sync.Mutex
}
func (d *defaultCallBackUpdate) UpdateEndpoints(operation config.Operation, endpoints ...*config.Endpoint) {
d.lock.Lock()
defer d.lock.Unlock()
switch operation {
case config.ADD:
for _, e := range endpoints {
if old, ok := d.endpoints[e.Name]; !ok {
d.endpoints[e.Name] = e
} else {
if e.Mode == 0 {
old.URL = e.URL
}
if e.Mode == 1 {
old.Weight = e.Weight
}
if e.Mode == 2 {
old.URL = e.URL
old.Weight = e.Weight
}
}
}
case config.SYNC:
for _, e := range endpoints {
if old, ok := d.endpoints[e.Name]; !ok {
d.endpoints[e.Name] = e
} else {
if e.Mode == 0 {
old.URL = e.URL
}
if e.Mode == 1 {
old.Weight = e.Weight
}
if e.Mode == 2 {
old.URL = e.URL
old.Weight = e.Weight
}
}
}
case config.DELETE:
for _, e := range endpoints {
if e.Mode == 0 {
if old, ok := d.endpoints[e.Name]; ok {
old.URL = ""
}
}
if e.Mode == 1 {
if old, ok := d.endpoints[e.Name]; ok {
old.Weight = 0
}
}
if e.Mode == 2 {
if _, ok := d.endpoints[e.Name]; ok {
delete(d.endpoints, e.Name)
}
}
}
case config.UPDATE:
for _, e := range endpoints {
if e.Mode == 0 {
if old, ok := d.endpoints[e.Name]; ok {
old.URL = e.URL
}
}
if e.Mode == 1 {
if old, ok := d.endpoints[e.Name]; ok {
old.Weight = e.Weight
}
}
if e.Mode == 2 {
if old, ok := d.endpoints[e.Name]; ok {
old.URL = e.URL
old.Weight = e.Weight
}
}
}
}
var re []*config.Endpoint
for _, v := range d.endpoints {
if v.URL != "" {
re = append(re, v)
}
}
d.callback.UpdateEndpoints(re...)
}
func (d *defaultCallBackUpdate) Error(err error) {
d.callback.Error(err)
}
func (e *etcdDiscover) AddProject(name string, callback Callback) {
e.lock.Lock()
defer e.lock.Unlock()
if _, ok := e.projects[name]; !ok {
cal := &defaultCallBackUpdate{
callback: callback,
endpoints: make(map[string]*config.Endpoint),
}
e.projects[name] = cal
go e.discover(name, cal)
}
}
func (e *etcdDiscover) AddUpdateProject(name string, callback CallbackUpdate) {
e.lock.Lock()
defer e.lock.Unlock()
if _, ok := e.projects[name]; !ok {
e.projects[name] = callback
go e.discover(name, callback)
}
}
func (e *etcdDiscover) Stop() {
e.cancel()
}
func (e *etcdDiscover) removeProject(name string) {
e.lock.Lock()
defer e.lock.Unlock()
if _, ok := e.projects[name]; ok {
delete(e.projects, name)
}
}
func (e *etcdDiscover) discover(name string, callback CallbackUpdate) {
watchChan, err := e.watcher.WatchList(e.ctx, fmt.Sprintf("%s/backends/%s/servers", e.prefix, name), "")
if err != nil {
callback.Error(err)
e.removeProject(name)
return
}
defer watchChan.Stop()
for event := range watchChan.ResultChan() {
if event.Source == nil {
continue
}
var end *config.Endpoint
if strings.HasSuffix(event.GetKey(), "/url") { //服务地址变化
kstep := strings.Split(event.GetKey(), "/")
if len(kstep) > 2 {
serverName := kstep[len(kstep)-2]
serverURL := event.GetValueString()
end = &config.Endpoint{Name: serverName, URL: serverURL, Mode: 0}
}
}
if strings.HasSuffix(event.GetKey(), "/weight") { //获取服务地址
kstep := strings.Split(event.GetKey(), "/")
if len(kstep) > 2 {
serverName := kstep[len(kstep)-2]
serverWeight := event.GetValueString()
weight, _ := strconv.Atoi(serverWeight)
end = &config.Endpoint{Name: serverName, Weight: weight, Mode: 1}
}
}
switch event.Type {
case watch.Added:
if end != nil {
callback.UpdateEndpoints(config.ADD, end)
}
case watch.Modified:
if end != nil {
callback.UpdateEndpoints(config.UPDATE, end)
}
case watch.Deleted:
if end != nil {
callback.UpdateEndpoints(config.DELETE, end)
}
case watch.Error:
callback.Error(event.Error)
logrus.Errorf("monitor discover get watch error: %s, remove this watch target first, and then sleep 10 sec, we will re-watch it", event.Error.Error())
e.removeProject(name)
time.Sleep(10 * time.Second)
e.AddUpdateProject(name, callback)
return
}
}
}
func makeEndpointForKvs(kvs []*mvccpb.KeyValue) (res []*config.Endpoint) {
var ends = make(map[string]*config.Endpoint)
for _, kv := range kvs {
if strings.HasSuffix(string(kv.Key), "/url") { //获取服务地址
kstep := strings.Split(string(kv.Key), "/")
if len(kstep) > 2 {
serverName := kstep[len(kstep)-2]
serverURL := string(kv.Value)
if en, ok := ends[serverName]; ok {
en.URL = serverURL
} else {
ends[serverName] = &config.Endpoint{Name: serverName, URL: serverURL}
}
}
}
if strings.HasSuffix(string(kv.Key), "/weight") { //获取服务权重
kstep := strings.Split(string(kv.Key), "/")
if len(kstep) > 2 {
serverName := kstep[len(kstep)-2]
serverWeight := string(kv.Value)
if en, ok := ends[serverName]; ok {
var err error
en.Weight, err = strconv.Atoi(serverWeight)
if err != nil {
logrus.Error("get server weight error.", err.Error())
}
} else {
weight, err := strconv.Atoi(serverWeight)
if err != nil {
logrus.Error("get server weight error.", err.Error())
}
ends[serverName] = &config.Endpoint{Name: serverName, Weight: weight}
}
}
}
}
for _, v := range ends {
res = append(res, v)
}
return
}