43 lines
914 B
Go
43 lines
914 B
Go
package htmlquery
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import (
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"sync"
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"github.com/antchfx/xpath"
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"github.com/golang/groupcache/lru"
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)
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// DisableSelectorCache will disable caching for the query selector if value is true.
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var DisableSelectorCache = false
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// SelectorCacheMaxEntries allows how many selector object can be caching. Default is 50.
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// Will disable caching if SelectorCacheMaxEntries <= 0.
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var SelectorCacheMaxEntries = 50
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var (
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cacheOnce sync.Once
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cache *lru.Cache
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cacheMutex sync.Mutex
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)
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func getQuery(expr string) (*xpath.Expr, error) {
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if DisableSelectorCache || SelectorCacheMaxEntries <= 0 {
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return xpath.Compile(expr)
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}
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cacheOnce.Do(func() {
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cache = lru.New(SelectorCacheMaxEntries)
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})
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cacheMutex.Lock()
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defer cacheMutex.Unlock()
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if v, ok := cache.Get(expr); ok {
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return v.(*xpath.Expr), nil
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}
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v, err := xpath.Compile(expr)
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if err != nil {
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return nil, err
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}
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cache.Add(expr, v)
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return v, nil
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}
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