Completely replace sync implementation

2020-04-11 10:37:54 +01:00
parent 6d553cb6fe
commit 39470c1b11
21 changed files with 435 additions and 1441 deletions
--- a/sync/etcd/etcd.go
+++ b/sync/etcd/etcd.go
@@ -0,0 +1,179 @@
+// Package etcd is an etcd implementation of lock
+package etcd
+
+import (
+	"context"
+	"errors"
+	"log"
+	"path"
+	"strings"
+	gosync "sync"
+
+	client "github.com/coreos/etcd/clientv3"
+	cc "github.com/coreos/etcd/clientv3/concurrency"
+	"github.com/micro/go-micro/v2/sync"
+)
+
+type etcdSync struct {
+	options sync.Options
+	path    string
+	client  *client.Client
+
+	mtx   gosync.Mutex
+	locks map[string]*etcdLock
+}
+
+type etcdLock struct {
+	s *cc.Session
+	m *cc.Mutex
+}
+
+type etcdLeader struct {
+	opts sync.LeaderOptions
+	s    *cc.Session
+	e    *cc.Election
+	id   string
+}
+
+func (e *etcdSync) Leader(id string, opts ...sync.LeaderOption) (sync.Leader, error) {
+	var options sync.LeaderOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// make path
+	path := path.Join(e.path, strings.Replace(e.options.Prefix+id, "/", "-", -1))
+
+	s, err := cc.NewSession(e.client)
+	if err != nil {
+		return nil, err
+	}
+
+	l := cc.NewElection(s, path)
+
+	if err := l.Campaign(context.TODO(), id); err != nil {
+		return nil, err
+	}
+
+	return &etcdLeader{
+		opts: options,
+		e:    l,
+		id:   id,
+	}, nil
+}
+
+func (e *etcdLeader) Status() chan bool {
+	ch := make(chan bool, 1)
+	ech := e.e.Observe(context.Background())
+
+	go func() {
+		for r := range ech {
+			if string(r.Kvs[0].Value) != e.id {
+				ch <- true
+				close(ch)
+				return
+			}
+		}
+	}()
+
+	return ch
+}
+
+func (e *etcdLeader) Resign() error {
+	return e.e.Resign(context.Background())
+}
+
+func (e *etcdSync) Init(opts ...sync.Option) error {
+	for _, o := range opts {
+		o(&e.options)
+	}
+	return nil
+}
+
+func (e *etcdSync) Options() sync.Options {
+	return e.options
+}
+
+func (e *etcdSync) Lock(id string, opts ...sync.LockOption) error {
+	var options sync.LockOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// make path
+	path := path.Join(e.path, strings.Replace(e.options.Prefix+id, "/", "-", -1))
+
+	var sopts []cc.SessionOption
+	if options.TTL > 0 {
+		sopts = append(sopts, cc.WithTTL(int(options.TTL.Seconds())))
+	}
+
+	s, err := cc.NewSession(e.client, sopts...)
+	if err != nil {
+		return err
+	}
+
+	m := cc.NewMutex(s, path)
+
+	if err := m.Lock(context.TODO()); err != nil {
+		return err
+	}
+
+	e.mtx.Lock()
+	e.locks[id] = &etcdLock{
+		s: s,
+		m: m,
+	}
+	e.mtx.Unlock()
+	return nil
+}
+
+func (e *etcdSync) Unlock(id string) error {
+	e.mtx.Lock()
+	defer e.mtx.Unlock()
+	v, ok := e.locks[id]
+	if !ok {
+		return errors.New("lock not found")
+	}
+	err := v.m.Unlock(context.Background())
+	delete(e.locks, id)
+	return err
+}
+
+func (e *etcdSync) String() string {
+	return "etcd"
+}
+
+func NewSync(opts ...sync.Option) sync.Sync {
+	var options sync.Options
+	for _, o := range opts {
+		o(&options)
+	}
+
+	var endpoints []string
+
+	for _, addr := range options.Nodes {
+		if len(addr) > 0 {
+			endpoints = append(endpoints, addr)
+		}
+	}
+
+	if len(endpoints) == 0 {
+		endpoints = []string{"http://127.0.0.1:2379"}
+	}
+
+	// TODO: parse addresses
+	c, err := client.New(client.Config{
+		Endpoints: endpoints,
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	return &etcdSync{
+		path:    "/micro/sync",
+		client:  c,
+		options: options,
+		locks:   make(map[string]*etcdLock),
+	}
+}