81 lines
1.3 KiB
Go
81 lines
1.3 KiB
Go
package lib
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import (
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"encoding/json"
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"os"
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)
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const cacheFile = "cache.json"
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type CacheItem struct {
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Fetcher string
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Value string
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}
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type Cache struct {
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Items []CacheItem
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}
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func (c *Cache) Update(fetcher string, value string) {
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for i := range c.Items {
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if c.Items[i].Fetcher == fetcher {
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c.Items[i].Value = value
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return
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}
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}
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c.Items = append(c.Items, CacheItem{
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Fetcher: fetcher,
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Value: value,
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})
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}
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func (c *Cache) Get(fetcher string) (string, bool) {
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for _, item := range c.Items {
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if item.Fetcher == fetcher {
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return item.Value, true
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}
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}
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return "", false
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}
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func (c *Cache) Has(fetcher string) bool {
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_, found := c.Get(fetcher)
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return found
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}
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func (c *Cache) IsChanged(fetcher string, value string) bool {
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cachedValue, found := c.Get(fetcher)
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if !found || cachedValue != value {
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return true
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}
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return false
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}
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func (c *Cache) TryUpdate(fetcher string, value string) bool {
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if c.IsChanged(fetcher, value) {
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c.Update(fetcher, value)
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return true
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}
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return false
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}
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func (c *Cache) Load() {
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f, err := os.Open(cacheFile)
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if err != nil {
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return
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}
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defer f.Close()
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_ = json.NewDecoder(f).Decode(&c.Items)
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}
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func (c *Cache) Save() {
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f, err := os.Create(cacheFile)
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if err != nil {
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return
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}
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defer f.Close()
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_ = json.NewEncoder(f).Encode(c.Items)
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}
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