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@@ -0,0 +1,107 @@
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+package bus
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+
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+import (
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+ "context"
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+ "fmt"
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+ "runtime"
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+ "sync"
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+)
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+
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+type InProcBus struct {
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+ ctx context.Context
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+ once sync.Once
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+ eventChan chan *Event
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+ subscriberLocker sync.RWMutex
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+ subscribers map[string]Subscriber
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+}
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+
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+func (bus *InProcBus) Subscribers() []Subscriber {
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+ bus.subscriberLocker.RLock()
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+ defer bus.subscriberLocker.RUnlock()
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+ vs := make([]Subscriber, len(bus.subscribers))
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+ i := 0
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+ for _, v := range bus.subscribers {
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+ vs[i] = v
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+ i++
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+ }
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+ return vs
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+}
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+
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+func (bus *InProcBus) worker() {
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+ for {
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+ select {
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+ case e, ok := <-bus.eventChan:
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+ if ok {
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+ _ = bus.Dispatch(e)
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+ }
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+ case <-bus.ctx.Done():
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+ return
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+ }
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+ }
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+}
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+
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+// Publish 发布一个事件
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+func (bus *InProcBus) Publish(e *Event) {
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+ bus.once.Do(func() {
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+ for i := 0; i < runtime.NumCPU(); i++ {
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+ go bus.worker()
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+ }
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+ })
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+ select {
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+ case bus.eventChan <- e:
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+ default:
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+ }
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+ return
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+}
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+
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+// Dispatch 分配事件,关心返回值
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+func (bus *InProcBus) Dispatch(e *Event) (err error) {
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+ return bus.DispatchCtx(context.Background(), e)
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+}
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+
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+func (bus *InProcBus) DispatchCtx(ctx context.Context, e *Event) (err error) {
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+ bus.subscriberLocker.RLock()
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+ defer bus.subscriberLocker.RUnlock()
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+ for _, sub := range bus.subscribers {
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+ if sub.HasTopic(e.Name) {
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+ err = sub.Process(ctx, e)
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+ }
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+ }
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+ releaseEvent(e)
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+ return
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+}
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+
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+func (bus *InProcBus) Subscribe(sub Subscriber) (err error) {
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+ bus.subscriberLocker.Lock()
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+ defer bus.subscriberLocker.Unlock()
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+ if _, ok := bus.subscribers[sub.ID()]; ok {
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+ err = fmt.Errorf("subscriber %s already exists", sub.ID())
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+ return
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+ }
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+ if err = sub.OnAttach(); err != nil {
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+ return
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+ }
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+ bus.subscribers[sub.ID()] = sub
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+ return
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+}
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+
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+func (bus *InProcBus) UnSubscribe(sub Subscriber) (err error) {
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+ bus.subscriberLocker.Lock()
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+ defer bus.subscriberLocker.Unlock()
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+ if instance, ok := bus.subscribers[sub.ID()]; !ok {
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+ err = fmt.Errorf("subscriber %s not exists", sub.ID())
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+ return
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+ } else {
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+ delete(bus.subscribers, sub.ID())
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+ err = instance.OnDetach()
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+ }
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+ return
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+}
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+
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+func NewInPrcBus(ctx context.Context) *InProcBus {
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+ return &InProcBus{
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+ ctx: ctx,
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+ eventChan: make(chan *Event, 100),
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+ subscribers: make(map[string]Subscriber),
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+ }
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+}
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