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kratos/pkg/naming/discovery/discovery.go

669 lines
15 KiB

package discovery
import (
"context"
"encoding/json"
"errors"
"fmt"
"math/rand"
"net/url"
"os"
"strconv"
"strings"
"sync"
"sync/atomic"
"time"
"github.com/bilibili/kratos/pkg/conf/env"
"github.com/bilibili/kratos/pkg/ecode"
"github.com/bilibili/kratos/pkg/log"
"github.com/bilibili/kratos/pkg/naming"
bm "github.com/bilibili/kratos/pkg/net/http/blademaster"
"github.com/bilibili/kratos/pkg/net/netutil"
"github.com/bilibili/kratos/pkg/net/netutil/breaker"
xstr "github.com/bilibili/kratos/pkg/str"
xtime "github.com/bilibili/kratos/pkg/time"
)
const (
_registerURL = "http://%s/discovery/register"
_setURL = "http://%s/discovery/set"
_cancelURL = "http://%s/discovery/cancel"
_renewURL = "http://%s/discovery/renew"
_pollURL = "http://%s/discovery/polls"
_nodesURL = "http://%s/discovery/nodes"
_registerGap = 30 * time.Second
_statusUP = "1"
)
const (
_appid = "infra.discovery"
)
var (
_ naming.Builder = &Discovery{}
_ naming.Registry = &Discovery{}
// ErrDuplication duplication treeid.
ErrDuplication = errors.New("discovery: instance duplicate registration")
)
// Config discovery configures.
type Config struct {
Nodes []string
Zone string
Env string
Host string
}
// Discovery is discovery client.
type Discovery struct {
once sync.Once
conf *Config
ctx context.Context
cancelFunc context.CancelFunc
httpClient *bm.Client
mutex sync.RWMutex
apps map[string]*appInfo
registry map[string]struct{}
lastHost string
cancelPolls context.CancelFunc
idx uint64
node atomic.Value
delete chan *appInfo
}
type appInfo struct {
zoneIns atomic.Value
resolver map[*Resolver]struct{}
lastTs int64 // latest timestamp
}
func fixConfig(c *Config) {
if len(c.Nodes) == 0 {
c.Nodes = []string{"NOTE: please config a default HOST"}
}
if env.Zone != "" {
c.Zone = env.Zone
}
if env.DeployEnv != "" {
c.Env = env.DeployEnv
}
if env.Hostname != "" {
c.Host = env.Hostname
} else {
c.Host, _ = os.Hostname()
}
}
var (
once sync.Once
_defaultDiscovery *Discovery
)
func initDefault() {
once.Do(func() {
_defaultDiscovery = New(nil)
})
}
// Builder return default discvoery resolver builder.
func Builder() naming.Builder {
if _defaultDiscovery == nil {
initDefault()
}
return _defaultDiscovery
}
// Build register resolver into default discovery.
func Build(id string) naming.Resolver {
if _defaultDiscovery == nil {
initDefault()
}
return _defaultDiscovery.Build(id)
}
// New new a discovery client.
func New(c *Config) (d *Discovery) {
if c == nil {
c = &Config{}
}
fixConfig(c)
ctx, cancel := context.WithCancel(context.Background())
d = &Discovery{
ctx: ctx,
cancelFunc: cancel,
conf: c,
apps: map[string]*appInfo{},
registry: map[string]struct{}{},
delete: make(chan *appInfo, 10),
}
// httpClient
cfg := &bm.ClientConfig{
Dial: xtime.Duration(3 * time.Second),
Timeout: xtime.Duration(40 * time.Second),
Breaker: &breaker.Config{
Window: 100,
Sleep: 3,
Bucket: 10,
Ratio: 0.5,
Request: 100,
},
}
d.httpClient = bm.NewClient(cfg)
resolver := d.Build(_appid)
event := resolver.Watch()
_, ok := <-event
if !ok {
panic("discovery watch failed")
}
ins, ok := resolver.Fetch(context.Background())
if ok {
d.newSelf(ins)
}
go d.selfproc(resolver, event)
return
}
func (d *Discovery) selfproc(resolver naming.Resolver, event <-chan struct{}) {
for {
_, ok := <-event
if !ok {
return
}
instances, ok := resolver.Fetch(context.Background())
if ok {
d.newSelf(instances)
}
}
}
func (d *Discovery) newSelf(instances *naming.InstancesInfo) {
ins, ok := instances.Instances[d.conf.Zone]
if !ok {
return
}
var nodes []string
for _, in := range ins {
for _, addr := range in.Addrs {
u, err := url.Parse(addr)
if err == nil && u.Scheme == "http" {
nodes = append(nodes, u.Host)
}
}
}
// diff old nodes
olds, ok := d.node.Load().([]string)
if ok {
var diff int
for _, n := range nodes {
for _, o := range olds {
if o == n {
diff++
break
}
}
}
if len(nodes) == diff {
return
}
}
rand.Shuffle(len(nodes), func(i, j int) {
nodes[i], nodes[j] = nodes[j], nodes[i]
})
d.node.Store(nodes)
}
// Build disovery resovler builder.
func (d *Discovery) Build(appid string) naming.Resolver {
r := &Resolver{
id: appid,
d: d,
event: make(chan struct{}, 1),
}
d.mutex.Lock()
app, ok := d.apps[appid]
if !ok {
app = &appInfo{
resolver: make(map[*Resolver]struct{}),
}
d.apps[appid] = app
cancel := d.cancelPolls
if cancel != nil {
cancel()
}
}
app.resolver[r] = struct{}{}
d.mutex.Unlock()
if ok {
select {
case r.event <- struct{}{}:
default:
}
}
log.Info("disocvery: AddWatch(%s) already watch(%v)", appid, ok)
d.once.Do(func() {
go d.serverproc()
})
return r
}
// Scheme return discovery's scheme
func (d *Discovery) Scheme() string {
return "discovery"
}
// Resolver discveory resolver.
type Resolver struct {
id string
event chan struct{}
d *Discovery
}
// Watch watch instance.
func (r *Resolver) Watch() <-chan struct{} {
return r.event
}
// Fetch fetch resolver instance.
func (r *Resolver) Fetch(c context.Context) (ins *naming.InstancesInfo, ok bool) {
r.d.mutex.RLock()
app, ok := r.d.apps[r.id]
r.d.mutex.RUnlock()
if ok {
ins, ok = app.zoneIns.Load().(*naming.InstancesInfo)
return
}
return
}
// Close close resolver.
func (r *Resolver) Close() error {
r.d.mutex.Lock()
if app, ok := r.d.apps[r.id]; ok && len(app.resolver) != 0 {
delete(app.resolver, r)
// TODO: delete app from builder
}
r.d.mutex.Unlock()
return nil
}
func (d *Discovery) pickNode() string {
nodes, ok := d.node.Load().([]string)
if !ok || len(nodes) == 0 {
return d.conf.Nodes[d.idx%uint64(len(d.conf.Nodes))]
}
return nodes[d.idx%uint64(len(nodes))]
}
func (d *Discovery) switchNode() {
atomic.AddUint64(&d.idx, 1)
}
// Reload reload the config
func (d *Discovery) Reload(c *Config) {
fixConfig(c)
d.mutex.Lock()
d.conf = c
d.mutex.Unlock()
}
// Close stop all running process including discovery and register
func (d *Discovery) Close() error {
d.cancelFunc()
return nil
}
// Register Register an instance with discovery and renew automatically
func (d *Discovery) Register(c context.Context, ins *naming.Instance) (cancelFunc context.CancelFunc, err error) {
d.mutex.Lock()
if _, ok := d.registry[ins.AppID]; ok {
err = ErrDuplication
} else {
d.registry[ins.AppID] = struct{}{}
}
d.mutex.Unlock()
if err != nil {
return
}
if err = d.register(c, ins); err != nil {
d.mutex.Lock()
delete(d.registry, ins.AppID)
d.mutex.Unlock()
return
}
ctx, cancel := context.WithCancel(d.ctx)
ch := make(chan struct{}, 1)
cancelFunc = context.CancelFunc(func() {
cancel()
<-ch
})
go func() {
ticker := time.NewTicker(_registerGap)
defer ticker.Stop()
for {
select {
case <-ticker.C:
if err := d.renew(ctx, ins); err != nil && ecode.NothingFound.Equal(err) {
d.register(ctx, ins)
}
case <-ctx.Done():
d.cancel(ins)
ch <- struct{}{}
return
}
}
}()
return
}
// Set set ins status and metadata.
func (d *Discovery) Set(ins *naming.Instance) error {
return d.set(context.Background(), ins)
}
// cancel Remove the registered instance from discovery
func (d *Discovery) cancel(ins *naming.Instance) (err error) {
d.mutex.RLock()
conf := d.conf
d.mutex.RUnlock()
res := new(struct {
Code int `json:"code"`
Message string `json:"message"`
})
uri := fmt.Sprintf(_cancelURL, d.pickNode())
params := d.newParams(conf)
params.Set("appid", ins.AppID)
// request
if err = d.httpClient.Post(context.Background(), uri, "", params, &res); err != nil {
d.switchNode()
log.Error("discovery cancel client.Get(%v) env(%s) appid(%s) hostname(%s) error(%v)",
uri, conf.Env, ins.AppID, conf.Host, err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
log.Warn("discovery cancel client.Get(%v) env(%s) appid(%s) hostname(%s) code(%v)",
uri, conf.Env, ins.AppID, conf.Host, res.Code)
err = ec
return
}
log.Info("discovery cancel client.Get(%v) env(%s) appid(%s) hostname(%s) success",
uri, conf.Env, ins.AppID, conf.Host)
return
}
// register Register an instance with discovery
func (d *Discovery) register(ctx context.Context, ins *naming.Instance) (err error) {
d.mutex.RLock()
conf := d.conf
d.mutex.RUnlock()
var metadata []byte
if ins.Metadata != nil {
if metadata, err = json.Marshal(ins.Metadata); err != nil {
log.Error("discovery:register instance Marshal metadata(%v) failed!error(%v)", ins.Metadata, err)
}
}
res := new(struct {
Code int `json:"code"`
Message string `json:"message"`
})
uri := fmt.Sprintf(_registerURL, d.pickNode())
params := d.newParams(conf)
params.Set("appid", ins.AppID)
params.Set("addrs", strings.Join(ins.Addrs, ","))
params.Set("version", ins.Version)
params.Set("status", _statusUP)
params.Set("metadata", string(metadata))
if err = d.httpClient.Post(ctx, uri, "", params, &res); err != nil {
d.switchNode()
log.Error("discovery: register client.Get(%v) zone(%s) env(%s) appid(%s) addrs(%v) error(%v)",
uri, conf.Zone, conf.Env, ins.AppID, ins.Addrs, err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
log.Warn("discovery: register client.Get(%v) env(%s) appid(%s) addrs(%v) code(%v)",
uri, conf.Env, ins.AppID, ins.Addrs, res.Code)
err = ec
return
}
log.Info("discovery: register client.Get(%v) env(%s) appid(%s) addrs(%s) success",
uri, conf.Env, ins.AppID, ins.Addrs)
return
}
// rset set instance info with discovery
func (d *Discovery) set(ctx context.Context, ins *naming.Instance) (err error) {
d.mutex.RLock()
conf := d.conf
d.mutex.RUnlock()
res := new(struct {
Code int `json:"code"`
Message string `json:"message"`
})
uri := fmt.Sprintf(_setURL, d.pickNode())
params := d.newParams(conf)
params.Set("appid", ins.AppID)
params.Set("version", ins.Version)
params.Set("status", strconv.FormatInt(ins.Status, 10))
if ins.Metadata != nil {
var metadata []byte
if metadata, err = json.Marshal(ins.Metadata); err != nil {
log.Error("discovery:set instance Marshal metadata(%v) failed!error(%v)", ins.Metadata, err)
}
params.Set("metadata", string(metadata))
}
if err = d.httpClient.Post(ctx, uri, "", params, &res); err != nil {
d.switchNode()
log.Error("discovery: set client.Get(%v) zone(%s) env(%s) appid(%s) addrs(%v) error(%v)",
uri, conf.Zone, conf.Env, ins.AppID, ins.Addrs, err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
log.Warn("discovery: set client.Get(%v) env(%s) appid(%s) addrs(%v) code(%v)",
uri, conf.Env, ins.AppID, ins.Addrs, res.Code)
err = ec
return
}
log.Info("discovery: set client.Get(%v) env(%s) appid(%s) addrs(%s) success",
uri+"?"+params.Encode(), conf.Env, ins.AppID, ins.Addrs)
return
}
// renew Renew an instance with discovery
func (d *Discovery) renew(ctx context.Context, ins *naming.Instance) (err error) {
d.mutex.RLock()
conf := d.conf
d.mutex.RUnlock()
res := new(struct {
Code int `json:"code"`
Message string `json:"message"`
})
uri := fmt.Sprintf(_renewURL, d.pickNode())
params := d.newParams(conf)
params.Set("appid", ins.AppID)
if err = d.httpClient.Post(ctx, uri, "", params, &res); err != nil {
d.switchNode()
log.Error("discovery: renew client.Get(%v) env(%s) appid(%s) hostname(%s) error(%v)",
uri, conf.Env, ins.AppID, conf.Host, err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
err = ec
if ec.Equal(ecode.NothingFound) {
return
}
log.Error("discovery: renew client.Get(%v) env(%s) appid(%s) hostname(%s) code(%v)",
uri, conf.Env, ins.AppID, conf.Host, res.Code)
return
}
return
}
func (d *Discovery) serverproc() {
var (
retry int
ctx context.Context
cancel context.CancelFunc
)
bc := netutil.DefaultBackoffConfig
ticker := time.NewTicker(time.Minute * 30)
defer ticker.Stop()
for {
if ctx == nil {
ctx, cancel = context.WithCancel(d.ctx)
d.mutex.Lock()
d.cancelPolls = cancel
d.mutex.Unlock()
}
select {
case <-d.ctx.Done():
return
default:
}
apps, err := d.polls(ctx, d.pickNode())
if err != nil {
d.switchNode()
if ctx.Err() == context.Canceled {
ctx = nil
continue
}
time.Sleep(bc.Backoff(retry))
retry++
continue
}
retry = 0
d.broadcast(apps)
}
}
func (d *Discovery) nodes() (nodes []string) {
res := new(struct {
Code int `json:"code"`
Data []struct {
Addr string `json:"addr"`
} `json:"data"`
})
uri := fmt.Sprintf(_nodesURL, d.pickNode())
if err := d.httpClient.Get(d.ctx, uri, "", nil, res); err != nil {
d.switchNode()
log.Error("discovery: consumer client.Get(%v)error(%+v)", uri, err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
log.Error("discovery: consumer client.Get(%v) error(%v)", uri, res.Code)
return
}
if len(res.Data) == 0 {
log.Warn("discovery: get nodes(%s) failed,no nodes found!", uri)
return
}
nodes = make([]string, 0, len(res.Data))
for i := range res.Data {
nodes = append(nodes, res.Data[i].Addr)
}
return
}
func (d *Discovery) polls(ctx context.Context, host string) (apps map[string]naming.InstancesInfo, err error) {
var (
lastTs []int64
appid []string
changed bool
)
if host != d.lastHost {
d.lastHost = host
changed = true
}
d.mutex.RLock()
conf := d.conf
for k, v := range d.apps {
if changed {
v.lastTs = 0
}
appid = append(appid, k)
lastTs = append(lastTs, v.lastTs)
}
d.mutex.RUnlock()
if len(appid) == 0 {
return
}
uri := fmt.Sprintf(_pollURL, host)
res := new(struct {
Code int `json:"code"`
Data map[string]naming.InstancesInfo `json:"data"`
})
params := url.Values{}
params.Set("env", conf.Env)
params.Set("hostname", conf.Host)
params.Set("appid", strings.Join(appid, ","))
params.Set("latest_timestamp", xstr.JoinInts(lastTs))
if err = d.httpClient.Get(ctx, uri, "", params, res); err != nil {
log.Error("discovery: client.Get(%s) error(%+v)", uri+"?"+params.Encode(), err)
return
}
if ec := ecode.Int(res.Code); !ec.Equal(ecode.OK) {
if !ec.Equal(ecode.NotModified) {
log.Error("discovery: client.Get(%s) get error code(%d)", uri+"?"+params.Encode(), res.Code)
err = ec
}
return
}
info, _ := json.Marshal(res.Data)
for _, app := range res.Data {
if app.LastTs == 0 {
err = ecode.ServerErr
log.Error("discovery: client.Get(%s) latest_timestamp is 0,instances:(%s)", uri+"?"+params.Encode(), info)
return
}
}
log.Info("discovery: polls uri(%s)", uri+"?"+params.Encode())
log.Info("discovery: successfully polls(%s) instances (%s)", uri+"?"+params.Encode(), info)
apps = res.Data
return
}
func (d *Discovery) broadcast(apps map[string]naming.InstancesInfo) {
for id, v := range apps {
var count int
for zone, ins := range v.Instances {
if len(ins) == 0 {
delete(v.Instances, zone)
}
count += len(ins)
}
if count == 0 {
continue
}
d.mutex.RLock()
app, ok := d.apps[id]
d.mutex.RUnlock()
if ok {
app.lastTs = v.LastTs
app.zoneIns.Store(v)
d.mutex.RLock()
for rs := range app.resolver {
select {
case rs.event <- struct{}{}:
default:
}
}
d.mutex.RUnlock()
}
}
}
func (d *Discovery) newParams(conf *Config) url.Values {
params := url.Values{}
params.Set("zone", conf.Zone)
params.Set("env", conf.Env)
params.Set("hostname", conf.Host)
return params
}