Victor_Jay
593b52096f
- 新增 internal/cache/home_cache.go，实现带 TTL 的首页文章列表内存缓存 - frontend.go 首页 handler 优先读取缓存，未命中/过期时查询 DB 并回填 - PostService 注入失效回调，在 Create/Update/Delete/Approve 后自动失效缓存 - 减少首页每次请求都查 DB 的开销
56 lines
1.3 KiB
Go
56 lines
1.3 KiB
Go
package cache
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import (
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"sync"
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"time"
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"metazone.cc/metalab/internal/model"
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)
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// HomePageCache 首页内存缓存，30 秒 TTL，创建/更新/删除/审核通过时失效
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type HomePageCache struct {
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mu sync.RWMutex
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posts []model.Post
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total int64
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expires time.Time
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ttl time.Duration
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}
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// NewHomePageCache 创建首页缓存，ttl 为缓存有效期
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func NewHomePageCache(ttl time.Duration) *HomePageCache {
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return &HomePageCache{ttl: ttl}
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}
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// Get 返回缓存数据，ok=false 表示缓存未命中或已过期
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func (c *HomePageCache) Get() (posts []model.Post, total int64, ok bool) {
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c.mu.RLock()
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defer c.mu.RUnlock()
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if time.Now().After(c.expires) {
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return nil, 0, false
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}
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// 返回浅拷贝以防止调用方修改缓存内部数据
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copied := make([]model.Post, len(c.posts))
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copy(copied, c.posts)
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return copied, c.total, true
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}
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// Set 写入缓存数据
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func (c *HomePageCache) Set(posts []model.Post, total int64) {
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c.mu.Lock()
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defer c.mu.Unlock()
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// 深拷贝一份避免外部修改影响缓存
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c.posts = make([]model.Post, len(posts))
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copy(c.posts, posts)
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c.total = total
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c.expires = time.Now().Add(c.ttl)
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}
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// Invalidate 主动失效缓存
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func (c *HomePageCache) Invalidate() {
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c.mu.Lock()
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defer c.mu.Unlock()
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c.posts = nil
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c.total = 0
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c.expires = time.Time{}
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}
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