frostfs-s3-gw/pkg/event/targetlist.go

149 lines
3.3 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018 MinIO, Inc.
*
* 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 (
"fmt"
"sync"
)
// Target - event target interface
type Target interface {
ID() TargetID
IsActive() (bool, error)
Save(Event) error
Send(string) error
Close() error
HasQueueStore() bool
}
// TargetList - holds list of targets indexed by target ID.
type TargetList struct {
sync.RWMutex
targets map[TargetID]Target
}
// Add - adds unique target to target list.
func (list *TargetList) Add(targets ...Target) error {
list.Lock()
defer list.Unlock()
for _, target := range targets {
if _, ok := list.targets[target.ID()]; ok {
return fmt.Errorf("target %v already exists", target.ID())
}
list.targets[target.ID()] = target
}
return nil
}
// Exists - checks whether target by target ID exists or not.
func (list *TargetList) Exists(id TargetID) bool {
list.RLock()
defer list.RUnlock()
_, found := list.targets[id]
return found
}
// TargetIDResult returns result of Remove/Send operation, sets err if
// any for the associated TargetID
type TargetIDResult struct {
// ID where the remove or send were initiated.
ID TargetID
// Stores any error while removing a target or while sending an event.
Err error
}
// Remove - closes and removes targets by given target IDs.
func (list *TargetList) Remove(targetIDSet TargetIDSet) {
list.Lock()
defer list.Unlock()
for id := range targetIDSet {
target, ok := list.targets[id]
if ok {
target.Close()
delete(list.targets, id)
}
}
}
// Targets - list all targets
func (list *TargetList) Targets() []Target {
list.RLock()
defer list.RUnlock()
targets := []Target{}
for _, tgt := range list.targets {
targets = append(targets, tgt)
}
return targets
}
// List - returns available target IDs.
func (list *TargetList) List() []TargetID {
list.RLock()
defer list.RUnlock()
keys := []TargetID{}
for k := range list.targets {
keys = append(keys, k)
}
return keys
}
// TargetMap - returns available targets.
func (list *TargetList) TargetMap() map[TargetID]Target {
list.RLock()
defer list.RUnlock()
return list.targets
}
// Send - sends events to targets identified by target IDs.
func (list *TargetList) Send(event Event, targetIDset TargetIDSet, resCh chan<- TargetIDResult) {
go func() {
var wg sync.WaitGroup
for id := range targetIDset {
list.RLock()
target, ok := list.targets[id]
list.RUnlock()
if ok {
wg.Add(1)
go func(id TargetID, target Target) {
defer wg.Done()
tgtRes := TargetIDResult{ID: id}
if err := target.Save(event); err != nil {
tgtRes.Err = err
}
resCh <- tgtRes
}(id, target)
} else {
resCh <- TargetIDResult{ID: id}
}
}
wg.Wait()
}()
}
// NewTargetList - creates TargetList.
func NewTargetList() *TargetList {
return &TargetList{targets: make(map[TargetID]Target)}
}