clair/ext/notification/driver.go
2017-01-22 23:02:50 -05:00

92 lines
2.5 KiB
Go

// Copyright 2017 clair authors
//
// 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 notification fetches notifications from the database and informs the
// specified remote handler about their existences, inviting the third party to
// actively query the API about it.
// Package notification exposes functions to dynamically register methods to
// deliver notifications from the Clair database.
package notification
import (
"sync"
"github.com/coreos/pkg/capnslog"
"github.com/coreos/clair/config"
"github.com/coreos/clair/database"
)
var (
log = capnslog.NewPackageLogger("github.com/coreos/clair", "ext/notification")
sendersM sync.RWMutex
senders = make(map[string]Sender)
)
// Sender represents anything that can transmit notifications.
type Sender interface {
// Configure attempts to initialize the notifier with the provided configuration.
// It returns whether the notifier is enabled or not.
Configure(*config.NotifierConfig) (bool, error)
// Send informs the existence of the specified notification.
Send(notification database.VulnerabilityNotification) error
}
// RegisterSender makes a Sender available by the provided name.
//
// If called twice with the same name, the name is blank, or if the provided
// Sender is nil, this function panics.
func RegisterSender(name string, s Sender) {
if name == "" {
panic("notification: could not register a Sender with an empty name")
}
if s == nil {
panic("notification: could not register a nil Sender")
}
sendersM.Lock()
defer sendersM.Unlock()
if _, dup := senders[name]; dup {
panic("notification: RegisterSender called twice for " + name)
}
senders[name] = s
}
// Senders returns the list of the registered Senders.
func Senders() map[string]Sender {
sendersM.RLock()
defer sendersM.RUnlock()
ret := make(map[string]Sender)
for k, v := range senders {
ret[k] = v
}
return ret
}
// UnregisterSender removes a Sender with a particular name from the list.
func UnregisterSender(name string) {
sendersM.Lock()
defer sendersM.Unlock()
delete(senders, name)
}