Sergey Filkin
92 lines
1.5 KiB
Go
92 lines
1.5 KiB
Go
package server
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import (
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"context"
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"sync"
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"time"
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"github.com/google/uuid"
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)
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const janitorInterval = 5 * time.Minute
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type PreviewStore struct {
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mu sync.Mutex
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items map[string]previewItem
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ttl time.Duration
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now func() time.Time
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}
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type previewItem struct {
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html []byte
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mime string
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filename string
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expires time.Time
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}
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func NewPreviewStore(ttl time.Duration) *PreviewStore {
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return &PreviewStore{
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items: make(map[string]previewItem),
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ttl: ttl,
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now: time.Now,
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}
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}
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func (s *PreviewStore) Put(html []byte, mime, filename string) string {
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s.mu.Lock()
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defer s.mu.Unlock()
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id := uuid.NewString()
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s.items[id] = previewItem{
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html: append([]byte(nil), html...),
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mime: mime,
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filename: filename,
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expires: s.now().Add(s.ttl),
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}
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return id
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}
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func (s *PreviewStore) Take(id string) (previewItem, bool) {
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s.mu.Lock()
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defer s.mu.Unlock()
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item, ok := s.items[id]
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if !ok {
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return previewItem{}, false
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}
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delete(s.items, id)
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if s.now().After(item.expires) {
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return previewItem{}, false
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}
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item.html = append([]byte(nil), item.html...)
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return item, true
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}
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func (s *PreviewStore) janitor(ctx context.Context) {
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ticker := time.NewTicker(janitorInterval)
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defer ticker.Stop()
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for {
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select {
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case <-ctx.Done():
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return
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case now := <-ticker.C:
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s.cleanupExpired(now)
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}
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}
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}
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func (s *PreviewStore) cleanupExpired(now time.Time) {
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s.mu.Lock()
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defer s.mu.Unlock()
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for id, item := range s.items {
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if now.After(item.expires) {
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delete(s.items, id)
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}
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}
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}
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