event_manager.go

// Copyright 2016 VMware, Inc. All Rights Reserved.
//
// Licensed 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 event

import (
	"github.com/vmware/vic/lib/portlayer/event/collector"
	"github.com/vmware/vic/lib/portlayer/event/events"
)

// EventManager will provide a basic event pub/sub implementation
type EventManager interface {

	// RegisterCollector a collector with the manager
	RegisterCollector(collector.Collector)

	// Collectors returns registered collectors
	Collectors() map[string]collector.Collector

	// Subscribe for event callbacks
	Subscribe(eventTopic string, caller string, callback func(events.Event)) Subscriber

	// Unsubscribe from event callbacks
	Unsubscribe(eventTopic string, caller string)

	// Subscribers will return the subscriber map
	Subscribers() map[string]map[string]Subscriber

	// Subscribed returns subscriber count
	Subscribed() int

	// Publish the event to the subscribers
	Publish(e events.Event)
}