route/vendor/github.com/mtneug/pkg/startstopper/map.go

123 lines
3.3 KiB
Go

// Copyright (c) 2016 Matthias Neugebauer
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
package startstopper
import (
"context"
"sync"
)
// Map maps string keys to StartStopper.
type Map interface {
sync.Locker
// AddAndStart adds a StartStopper to the store and starts it.
AddAndStart(ctx context.Context, key string, ss StartStopper) (changed bool, err error)
// UpdateAndRestart stops the old version of the StartStopper, replaces it
// with the started new one.
UpdateAndRestart(ctx context.Context, key string, ss StartStopper) (changed bool, err error)
// DeleteAndStop stops the StartStopper and deletes it. If it is not in the
// store no change is made.
DeleteAndStop(ctx context.Context, key string) (changed bool, err error)
// Get the StartStopper of given key.
Get(key string) (ss StartStopper, ok bool)
// ForEach executes the given function for each StartStopper passing it and
// its key as arguments.
ForEach(func(key string, ss StartStopper))
// Len returns how many StartStopper are stored.
Len() int
}
type inMemoryMap struct {
sync.Mutex
store map[string]StartStopper
}
// NewInMemoryMap creates a new Map that stores
// StartStopper in memory.
func NewInMemoryMap() Map {
return &inMemoryMap{
store: make(map[string]StartStopper),
}
}
func (i *inMemoryMap) Len() int {
return len(i.store)
}
func (i *inMemoryMap) Get(key string) (ss StartStopper, ok bool) {
ss, ok = i.store[key]
return
}
func (i *inMemoryMap) AddAndStart(ctx context.Context, key string, ss StartStopper) (changed bool, err error) {
_, ok := i.store[key]
if !ok {
err = ss.Start(ctx)
if err != nil {
return
}
i.store[key] = ss
changed = true
}
return
}
func (i *inMemoryMap) UpdateAndRestart(ctx context.Context, key string, ss StartStopper) (changed bool, err error) {
changed, err = i.DeleteAndStop(ctx, key)
if err != nil {
return
}
changed2, err := i.AddAndStart(ctx, key, ss)
changed = changed || changed2
return
}
func (i *inMemoryMap) DeleteAndStop(ctx context.Context, key string) (changed bool, err error) {
ss, ok := i.store[key]
if ok {
err = ss.Stop(ctx)
if err != nil {
return
}
delete(i.store, key)
changed = true
}
return
}
func (i *inMemoryMap) ForEach(f func(key string, ss StartStopper)) {
for key, ss := range i.store {
f(key, ss)
}
}