server/pubsub/event_handler.go

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package pubsub

import (
	"strings"

	"github.com/go-chassis/openlog"
	"github.com/hashicorp/serf/cmd/serf/command/agent"
	"github.com/hashicorp/serf/serf"
)

var handlers = make(map[string]agent.EventHandler)

func RegisterHandler(typ string, h agent.EventHandler) {
	handlers[typ] = h
	openlog.Info("register handler for:" + typ)
}

// ClusterEventHandler handler serf custom event, it is singleton
type ClusterEventHandler struct {
}

// HandleEvent send event to subscribers
func (h *ClusterEventHandler) HandleEvent(e serf.Event) {
	openlog.Debug("receive event:" + e.EventType().String())
	switch e.EventType().String() {
	case "user":
		h.DispatchEvent(e)
	}

}

func (h *ClusterEventHandler) DispatchEvent(e serf.Event) {
	typ := strings.Replace(e.String(), "user-event: ", "", 1)
	eh, ok := handlers[typ]
	if !ok {
		openlog.Warn("can not handle:" + typ)
		return
	}
	eh.HandleEvent(e)
}