74 lines
1.4 KiB
Go
74 lines
1.4 KiB
Go
package cache
|
|
|
|
import (
|
|
"log"
|
|
"os"
|
|
"path/filepath"
|
|
)
|
|
|
|
func (c *Cache) Fetch(relPath string) (*CacheFile, error) {
|
|
// return file directly if exists in cache
|
|
cf, err := getCachedFile(c.cfg.cacheRoot, relPath)
|
|
if err == nil {
|
|
return cf, nil
|
|
}
|
|
|
|
// fetch file from upstream
|
|
_, err, _ = c.sf.Do(relPath, func() (any, error) {
|
|
// #log
|
|
log.Print("calling fetch")
|
|
return nil, c.fetch(relPath)
|
|
})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
cf, err = getCachedFile(c.cfg.cacheRoot, relPath)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return cf, nil
|
|
}
|
|
|
|
func (c *Cache) fetch(relPath string) error {
|
|
// relPath is relative to the localRoot
|
|
// ie relPath includes /{repo}/os/{arch}/ and the actual name linux-x.x.x.pkg.tar.zst
|
|
|
|
// final file name and path
|
|
destPath := filepath.Join(c.cfg.cacheRoot, relPath)
|
|
|
|
// declare vars outside loop
|
|
var err error
|
|
// fetch pkgs from mirror with retry logic
|
|
for range len(c.cfg.mirrorURLs) {
|
|
url := c.nextMirror() + relPath
|
|
err = downloadToDisk(url, destPath, c.client)
|
|
if err == nil {
|
|
break
|
|
}
|
|
}
|
|
if err != nil {
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func getCachedFile(cacheRoot, relPath string) (*CacheFile, error) {
|
|
filePath := filepath.Join(cacheRoot, relPath)
|
|
info, err := os.Stat(filePath)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
f, err := os.Open(filePath)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return &CacheFile{
|
|
Reader: f,
|
|
Size: info.Size(),
|
|
Filename: filepath.Base(filePath),
|
|
}, nil
|
|
}
|