42 lines
1.1 KiB
Go
42 lines
1.1 KiB
Go
 
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package fetcher
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import (
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"crypto/sha256"
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"fmt"
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"os"
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"path/filepath"
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)
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// cacheRead returns the cached bytes for the given cache key, or (nil, false)
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// on a miss (key not present, dir empty, or any read error).
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func cacheRead(dir, key string) ([]byte, bool) {
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if dir == "" {
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return nil, false
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}
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data, err := os.ReadFile(cachePath(dir, key))
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if err != nil {
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return nil, false
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}
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return data, true
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}
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// cacheWrite stores bytes in the cache for the given key. Write errors are
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// silently ignored so cache failures never block the normal fetch path.
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func cacheWrite(dir, key string, data []byte) {
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if dir == "" {
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return
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}
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if err := os.MkdirAll(dir, 0o755); err != nil {
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return
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}
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_ = os.WriteFile(cachePath(dir, key), data, 0o644)
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}
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// cachePath returns the filesystem path for a cache entry.
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// The filename is the SHA-256 hex digest of the key so arbitrary keys (URLs,
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// "project:file@ref" strings) map to safe, stable filenames.
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func cachePath(dir, key string) string {
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h := sha256.Sum256([]byte(key))
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return filepath.Join(dir, fmt.Sprintf("%x.yml", h))
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}
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