init

backend/providers/event/config.go

@@ -0,0 +1,99 @@
+package event
+
+import (
+	"context"
+
+	"github.com/ThreeDotsLabs/watermill"
+	"github.com/ThreeDotsLabs/watermill/message"
+	"go.ipao.vip/atom/container"
+	"go.ipao.vip/atom/contracts"
+	"go.ipao.vip/atom/opt"
+)
+
+const DefaultPrefix = "Events"
+
+func DefaultProvider() container.ProviderContainer {
+	return container.ProviderContainer{
+		Provider: ProvideChannel,
+		Options: []opt.Option{
+			opt.Prefix(DefaultPrefix),
+		},
+	}
+}
+
+type Config struct {
+	Sql   *ConfigSql
+	Kafka *ConfigKafka
+	Redis *ConfigRedis
+}
+
+type ConfigSql struct {
+	ConsumerGroup string
+}
+
+type ConfigRedis struct {
+	ConsumerGroup string
+	Streams       []string
+}
+
+type ConfigKafka struct {
+	ConsumerGroup string
+	Brokers       []string
+}
+
+type PubSub struct {
+	Router *message.Router
+
+	publishers  map[contracts.Channel]message.Publisher
+	subscribers map[contracts.Channel]message.Subscriber
+}
+
+func (ps *PubSub) Serve(ctx context.Context) error {
+	if err := ps.Router.Run(ctx); err != nil {
+		return err
+	}
+	return nil
+}
+
+// publish
+func (ps *PubSub) Publish(e contracts.EventPublisher) error {
+	if e == nil {
+		return nil
+	}
+
+	payload, err := e.Marshal()
+	if err != nil {
+		return err
+	}
+
+	msg := message.NewMessage(watermill.NewUUID(), payload)
+	return ps.getPublisher(e.Channel()).Publish(e.Topic(), msg)
+}
+
+// getPublisher returns the publisher for the specified channel.
+func (ps *PubSub) getPublisher(channel contracts.Channel) message.Publisher {
+	if pub, ok := ps.publishers[channel]; ok {
+		return pub
+	}
+	return ps.publishers[Go]
+}
+
+func (ps *PubSub) getSubscriber(channel contracts.Channel) message.Subscriber {
+	if sub, ok := ps.subscribers[channel]; ok {
+		return sub
+	}
+	return ps.subscribers[Go]
+}
+
+func (ps *PubSub) Handle(handlerName string, sub contracts.EventHandler) {
+	publishToCh, publishToTopic := sub.PublishTo()
+
+	ps.Router.AddHandler(
+		handlerName,
+		sub.Topic(),
+		ps.getSubscriber(sub.Channel()),
+		publishToTopic,
+		ps.getPublisher(publishToCh),
+		sub.Handler,
+	)
+}