gitea/modules/cache/context.go

93 lines
2.2 KiB
Go

// Copyright 2022 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package cache
import (
"context"
"sync"
"code.gitea.io/gitea/modules/log"
)
// cacheContext is a context that can be used to cache data in a request level context
// This is useful for caching data that is expensive to calculate and is likely to be
// used multiple times in a request.
type cacheContext struct {
ctx context.Context
data map[any]map[any]any
lock sync.RWMutex
}
func (cc *cacheContext) Get(tp, key any) any {
cc.lock.RLock()
defer cc.lock.RUnlock()
if cc.data[tp] == nil {
return nil
}
return cc.data[tp][key]
}
func (cc *cacheContext) Put(tp, key, value any) {
cc.lock.Lock()
defer cc.lock.Unlock()
if cc.data[tp] == nil {
cc.data[tp] = make(map[any]any)
}
cc.data[tp][key] = value
}
func (cc *cacheContext) Delete(tp, key any) {
cc.lock.Lock()
defer cc.lock.Unlock()
if cc.data[tp] == nil {
return
}
delete(cc.data[tp], key)
}
var cacheContextKey = struct{}{}
func WithCacheContext(ctx context.Context) context.Context {
return context.WithValue(ctx, cacheContextKey, &cacheContext{
ctx: ctx,
data: make(map[any]map[any]any),
})
}
func GetContextData(ctx context.Context, tp, key any) any {
if c, ok := ctx.Value(cacheContextKey).(*cacheContext); ok {
return c.Get(tp, key)
}
log.Warn("cannot get cache context when getting data: %v", ctx)
return nil
}
func SetContextData(ctx context.Context, tp, key, value any) {
if c, ok := ctx.Value(cacheContextKey).(*cacheContext); ok {
c.Put(tp, key, value)
return
}
log.Warn("cannot get cache context when setting data: %v", ctx)
}
func RemoveContextData(ctx context.Context, tp, key any) {
if c, ok := ctx.Value(cacheContextKey).(*cacheContext); ok {
c.Delete(tp, key)
}
}
// GetWithContextCache returns the cache value of the given key in the given context.
func GetWithContextCache[T any](ctx context.Context, cacheGroupKey string, cacheTargetID any, f func() (T, error)) (T, error) {
v := GetContextData(ctx, cacheGroupKey, cacheTargetID)
if vv, ok := v.(T); ok {
return vv, nil
}
t, err := f()
if err != nil {
return t, err
}
SetContextData(ctx, cacheGroupKey, cacheTargetID, t)
return t, nil
}