micro/broker/memory/memory.go

181 lines
3.1 KiB
Go

// Package memory provides a memory broker
package memory
import (
"context"
"errors"
"math/rand"
"sync"
"time"
"github.com/google/uuid"
"github.com/micro/go-micro/v3/broker"
maddr "github.com/micro/go-micro/v3/util/addr"
mnet "github.com/micro/go-micro/v3/util/net"
)
type memoryBroker struct {
opts broker.Options
addr string
sync.RWMutex
connected bool
Subscribers map[string][]*memorySubscriber
}
type memorySubscriber struct {
id string
topic string
exit chan bool
handler broker.Handler
opts broker.SubscribeOptions
}
func (m *memoryBroker) Options() broker.Options {
return m.opts
}
func (m *memoryBroker) Address() string {
return m.addr
}
func (m *memoryBroker) Connect() error {
m.Lock()
defer m.Unlock()
if m.connected {
return nil
}
// use 127.0.0.1 to avoid scan of all network interfaces
addr, err := maddr.Extract("127.0.0.1")
if err != nil {
return err
}
i := rand.Intn(20000)
// set addr with port
addr = mnet.HostPort(addr, 10000+i)
m.addr = addr
m.connected = true
return nil
}
func (m *memoryBroker) Disconnect() error {
m.Lock()
defer m.Unlock()
if !m.connected {
return nil
}
m.connected = false
return nil
}
func (m *memoryBroker) Init(opts ...broker.Option) error {
for _, o := range opts {
o(&m.opts)
}
return nil
}
func (m *memoryBroker) Publish(topic string, msg *broker.Message, opts ...broker.PublishOption) error {
m.RLock()
if !m.connected {
m.RUnlock()
return errors.New("not connected")
}
subs, ok := m.Subscribers[topic]
m.RUnlock()
if !ok {
return nil
}
for _, sub := range subs {
if err := sub.handler(msg); err != nil {
continue
}
}
return nil
}
func (m *memoryBroker) Subscribe(topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
m.RLock()
if !m.connected {
m.RUnlock()
return nil, errors.New("not connected")
}
m.RUnlock()
var options broker.SubscribeOptions
for _, o := range opts {
o(&options)
}
sub := &memorySubscriber{
exit: make(chan bool, 1),
id: uuid.New().String(),
topic: topic,
handler: handler,
opts: options,
}
m.Lock()
m.Subscribers[topic] = append(m.Subscribers[topic], sub)
m.Unlock()
go func() {
<-sub.exit
m.Lock()
var newSubscribers []*memorySubscriber
for _, sb := range m.Subscribers[topic] {
if sb.id == sub.id {
continue
}
newSubscribers = append(newSubscribers, sb)
}
m.Subscribers[topic] = newSubscribers
m.Unlock()
}()
return sub, nil
}
func (m *memoryBroker) String() string {
return "memory"
}
func (m *memorySubscriber) Options() broker.SubscribeOptions {
return m.opts
}
func (m *memorySubscriber) Topic() string {
return m.topic
}
func (m *memorySubscriber) Unsubscribe() error {
m.exit <- true
return nil
}
func NewBroker(opts ...broker.Option) broker.Broker {
options := broker.Options{
Context: context.Background(),
}
rand.Seed(time.Now().UnixNano())
for _, o := range opts {
o(&options)
}
return &memoryBroker{
opts: options,
Subscribers: make(map[string][]*memorySubscriber),
}
}