35 lines
824 B
Go
35 lines
824 B
Go
package cache
|
|
|
|
import (
|
|
"crypto/sha256"
|
|
"fmt"
|
|
"io"
|
|
"os"
|
|
)
|
|
|
|
// HashFile computes the SHA-256 hex digest of the file at path.
|
|
func HashFile(path string) (string, error) {
|
|
f, err := os.Open(path)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
defer f.Close()
|
|
h := sha256.New()
|
|
if _, err := io.Copy(h, f); err != nil {
|
|
return "", err
|
|
}
|
|
return fmt.Sprintf("%x", h.Sum(nil)), nil
|
|
}
|
|
|
|
// AnalysisKey builds a cache key for FFF or SLA analysis.
|
|
// Format: "<endpoint>:<filehash>:scale=<scale>"
|
|
// scale uses %.6g so "1.50" and "1.5" map to the same key.
|
|
func AnalysisKey(endpoint, fileHash string, scale float64) string {
|
|
return fmt.Sprintf("%s:%s:scale=%.6g", endpoint, fileHash, scale)
|
|
}
|
|
|
|
// ThumbnailKey builds a cache key for thumbnail generation.
|
|
func ThumbnailKey(fileHash string) string {
|
|
return "thumbnail:" + fileHash
|
|
}
|