beego/client/cache/write_delete.go

97 lines
3.2 KiB
Go

// Copyright 2014 beego Author. All Rights Reserved.
//
// 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 cache
import (
"context"
"errors"
"fmt"
"time"
"github.com/beego/beego/v2/core/berror"
)
type WriteDeleteCache struct {
Cache
storeFunc func(ctx context.Context, key string, val any) error
}
// NewWriteDeleteCache creates a write delete cache pattern decorator.
// The fn is the function that persistent the key and val.
func NewWriteDeleteCache(cache Cache, fn func(ctx context.Context, key string, val any) error) (*WriteDeleteCache, error) {
if fn == nil || cache == nil {
return nil, berror.Error(InvalidInitParameters, "cache or storeFunc can not be nil")
}
w := &WriteDeleteCache{
Cache: cache,
storeFunc: fn,
}
return w, nil
}
func (w *WriteDeleteCache) Set(ctx context.Context, key string, val any) error {
err := w.storeFunc(ctx, key, val)
if err != nil && !errors.Is(err, context.DeadlineExceeded) {
return berror.Wrap(err, PersistCacheFailed, fmt.Sprintf("key: %s, val: %v", key, val))
}
return w.Cache.Delete(ctx, key)
}
// WriteDoubleDeleteCache creates write double delete cache pattern decorator.
// The fn is the function that persistent the key and val.
// it will delete the key from cache when you call Set function, and wait for interval, it will delete the key from cache one more time.
// This pattern help to reduce the possibility of data inconsistencies, but it's still possible to be inconsistent among database and cache.
type WriteDoubleDeleteCache struct {
Cache
interval time.Duration
timeout time.Duration
storeFunc func(ctx context.Context, key string, val any) error
}
type WriteDoubleDeleteCacheOption func(c *WriteDoubleDeleteCache)
func NewWriteDoubleDeleteCache(cache Cache, interval, timeout time.Duration,
fn func(ctx context.Context, key string, val any) error) (*WriteDoubleDeleteCache, error) {
if fn == nil || cache == nil {
return nil, berror.Error(InvalidInitParameters, "cache or storeFunc can not be nil")
}
return &WriteDoubleDeleteCache{
Cache: cache,
interval: interval,
timeout: timeout,
storeFunc: fn,
}, nil
}
func (c *WriteDoubleDeleteCache) Set(
ctx context.Context, key string, val any) error {
err := c.storeFunc(ctx, key, val)
if err != nil && !errors.Is(err, context.DeadlineExceeded) {
return berror.Wrap(err, PersistCacheFailed, fmt.Sprintf("key: %s, val: %v", key, val))
}
time.AfterFunc(c.interval, func() {
rCtx, cancel := context.WithTimeout(context.Background(), c.timeout)
_ = c.Cache.Delete(rCtx, key)
cancel()
})
err = c.Cache.Delete(ctx, key)
if err != nil {
return berror.Wrap(err, DeleteFailed, fmt.Sprintf("write double delete pattern failed to delete the key: %s", key))
}
return nil
}