goldsmith/cache.go

95 lines
1.9 KiB
Go
Raw Normal View History

2018-12-08 19:18:51 +00:00
package goldsmith
import (
"encoding/binary"
"fmt"
"hash/crc32"
2023-11-11 19:04:37 +00:00
"io"
2018-12-08 19:18:51 +00:00
"os"
"path/filepath"
"sort"
2023-12-10 17:41:50 +00:00
"strings"
2018-12-08 19:18:51 +00:00
)
2018-12-10 01:00:46 +00:00
type cache struct {
2018-12-08 19:18:51 +00:00
baseDir string
}
func (self *cache) retrieveFile(context *Context, outputPath string, inputFiles []*File) (*File, error) {
cachePath, err := self.buildCachePath(context, outputPath, inputFiles)
2018-12-08 19:18:51 +00:00
if err != nil {
return nil, err
}
outputFile, err := context.CreateFileFromAsset(outputPath, cachePath)
if err != nil {
if os.IsNotExist(err) {
return nil, nil
}
return nil, err
}
return outputFile, nil
}
func (self *cache) storeFile(context *Context, outputFile *File, inputFiles []*File) error {
cachePath, err := self.buildCachePath(context, outputFile.Path(), inputFiles)
2018-12-08 19:18:51 +00:00
if err != nil {
return err
}
if err := os.MkdirAll(self.baseDir, 0755); err != nil {
2018-12-08 19:18:51 +00:00
return err
}
fp, err := os.Create(cachePath)
if err != nil {
return err
}
defer fp.Close()
2023-11-11 19:04:37 +00:00
offset, err := outputFile.Seek(0, io.SeekCurrent)
2018-12-08 19:18:51 +00:00
if err != nil {
return err
}
2023-11-11 19:04:37 +00:00
if _, err := outputFile.Seek(0, io.SeekStart); err != nil {
2018-12-08 19:18:51 +00:00
return err
}
if _, err := outputFile.WriteTo(fp); err != nil {
return err
}
2023-11-11 19:04:37 +00:00
if _, err := outputFile.Seek(offset, io.SeekStart); err != nil {
2018-12-08 19:18:51 +00:00
return err
}
return nil
}
func (self *cache) buildCachePath(context *Context, outputPath string, inputFiles []*File) (string, error) {
2018-12-08 19:18:51 +00:00
hasher := crc32.NewIEEE()
hasher.Write([]byte(outputPath))
2023-12-10 17:41:50 +00:00
sort.Slice(inputFiles, func(i, j int) bool {
return strings.Compare(inputFiles[i].Path(), inputFiles[j].Path()) < 0
})
2018-12-08 19:18:51 +00:00
for _, inputFile := range inputFiles {
modTimeBuff := make([]byte, 8)
binary.LittleEndian.PutUint64(modTimeBuff, uint64(inputFile.ModTime().UnixNano()))
2018-12-08 19:18:51 +00:00
hasher.Write([]byte(inputFile.Path()))
hasher.Write(modTimeBuff)
2018-12-08 19:18:51 +00:00
}
cachePath := filepath.Join(self.baseDir, fmt.Sprintf(
2018-12-08 19:18:51 +00:00
"gs_%.8x%s",
hasher.Sum32(),
filepath.Ext(outputPath),
))
return cachePath, nil
}