traefik/vendor/github.com/mesos/mesos-go/detector/interface.go
2017-03-09 13:13:02 +01:00

68 lines
2.5 KiB
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 detector
import (
mesos "github.com/mesos/mesos-go/mesosproto"
)
type MasterChanged interface {
// Invoked when the master changes
OnMasterChanged(*mesos.MasterInfo)
}
// AllMasters defines an optional interface that, if implemented by the same
// struct as implements MasterChanged, will receive an additional callbacks
// independently of leadership changes. it's possible that, as a result of a
// leadership change, both the OnMasterChanged and UpdatedMasters callbacks
// would be invoked.
//
// **NOTE:** Detector implementations are not required to support this optional
// interface. Please RTFM of the detector implementation that you want to use.
type AllMasters interface {
// UpdatedMasters is invoked upon a change in the membership of mesos
// masters, and is useful to clients that wish to know the entire set
// of Mesos masters currently running.
UpdatedMasters([]*mesos.MasterInfo)
}
// func/interface adapter
type OnMasterChanged func(*mesos.MasterInfo)
func (f OnMasterChanged) OnMasterChanged(mi *mesos.MasterInfo) {
f(mi)
}
// An abstraction of a Master detector which can be used to
// detect the leading master from a group.
type Master interface {
// Detect new master election. Every time a new master is elected, the
// detector will alert the observer. The first call to Detect is expected
// to kickstart any background detection processing (and not before then).
// If detection startup fails, or the listener cannot be added, then an
// error is returned.
Detect(MasterChanged) error
// returns a chan that, when closed, indicates the detector has terminated
Done() <-chan struct{}
// cancel the detector. it's ok to call this multiple times, or even if
// Detect() hasn't been invoked yet.
Cancel()
}