milvus/pkg/util/lifetime/lifetime.go
yah01 be980fbc38
Refine state check (#27541)
Signed-off-by: yah01 <yah2er0ne@outlook.com>
2023-10-11 21:01:35 +08:00

105 lines
2.8 KiB
Go

// Licensed to the LF AI & Data foundation 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 lifetime provides common component lifetime control logic.
package lifetime
import (
"sync"
)
// Lifetime interface for lifetime control.
type Lifetime[T any] interface {
SafeChan
// SetState is the method to change lifetime state.
SetState(state T)
// GetState returns current state.
GetState() T
// Add records a task is running, returns false if the lifetime is not healthy.
Add(isHealthy CheckHealth[T]) error
// Done records a task is done.
Done()
// Wait waits until all tasks are done.
Wait()
}
// CheckHealth function type for lifetime healthy check.
type CheckHealth[T any] func(T) error
var _ Lifetime[any] = (*lifetime[any])(nil)
// NewLifetime returns a new instance of Lifetime with init state and isHealthy logic.
func NewLifetime[T any](initState T) Lifetime[T] {
return &lifetime[T]{
safeChan: newSafeChan(),
state: initState,
}
}
// lifetime implementation of Lifetime.
// users shall not care about the internal fields of this struct.
type lifetime[T any] struct {
*safeChan
// wg is used for keeping record each running task.
wg sync.WaitGroup
// state is the "atomic" value to store component state.
state T
// mut is the rwmutex to control each task and state change event.
mut sync.RWMutex
// isHealthy is the method to check whether is legal to add a task.
isHealthy func(int32) error
}
// SetState is the method to change lifetime state.
func (l *lifetime[T]) SetState(state T) {
l.mut.Lock()
defer l.mut.Unlock()
l.state = state
}
// GetState returns current state.
func (l *lifetime[T]) GetState() T {
l.mut.RLock()
defer l.mut.RUnlock()
return l.state
}
// Add records a task is running, returns false if the lifetime is not healthy.
func (l *lifetime[T]) Add(checkHealth CheckHealth[T]) error {
l.mut.RLock()
defer l.mut.RUnlock()
// check lifetime healthy
if err := checkHealth(l.state); err != nil {
return err
}
l.wg.Add(1)
return nil
}
// Done records a task is done.
func (l *lifetime[T]) Done() {
l.wg.Done()
}
// Wait waits until all tasks are done.
func (l *lifetime[T]) Wait() {
l.wg.Wait()
}