Imported Upstream version 1.0.1

files/package_pool.go

@@ -0,0 +1,169 @@
+package files
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sync"
+
+	"github.com/smira/aptly/aptly"
+)
+
+// PackagePool is deduplicated storage of package files on filesystem
+type PackagePool struct {
+	sync.Mutex
+	rootPath string
+}
+
+// Check interface
+var (
+	_ aptly.PackagePool = (*PackagePool)(nil)
+)
+
+// NewPackagePool creates new instance of PackagePool which specified root
+func NewPackagePool(root string) *PackagePool {
+	return &PackagePool{rootPath: filepath.Join(root, "pool")}
+}
+
+// RelativePath returns path relative to pool's root for package files given MD5 and original filename
+func (pool *PackagePool) RelativePath(filename string, hashMD5 string) (string, error) {
+	filename = filepath.Base(filename)
+	if filename == "." || filename == "/" {
+		return "", fmt.Errorf("filename %s is invalid", filename)
+	}
+
+	if len(hashMD5) < 4 {
+		return "", fmt.Errorf("unable to compute pool location for filename %v, MD5 is missing", filename)
+	}
+
+	return filepath.Join(hashMD5[0:2], hashMD5[2:4], filename), nil
+}
+
+// Path returns full path to package file in pool given any name and hash of file contents
+func (pool *PackagePool) Path(filename string, hashMD5 string) (string, error) {
+	relative, err := pool.RelativePath(filename, hashMD5)
+	if err != nil {
+		return "", err
+	}
+
+	return filepath.Join(pool.rootPath, relative), nil
+}
+
+// FilepathList returns file paths of all the files in the pool
+func (pool *PackagePool) FilepathList(progress aptly.Progress) ([]string, error) {
+	pool.Lock()
+	defer pool.Unlock()
+
+	dirs, err := ioutil.ReadDir(pool.rootPath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, err
+	}
+
+	if len(dirs) == 0 {
+		return nil, nil
+	}
+
+	if progress != nil {
+		progress.InitBar(int64(len(dirs)), false)
+		defer progress.ShutdownBar()
+	}
+
+	result := []string{}
+
+	for _, dir := range dirs {
+		err = filepath.Walk(filepath.Join(pool.rootPath, dir.Name()), func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+			if !info.IsDir() {
+				result = append(result, path[len(pool.rootPath)+1:])
+			}
+			return nil
+		})
+		if err != nil {
+			return nil, err
+		}
+
+		if progress != nil {
+			progress.AddBar(1)
+		}
+	}
+
+	return result, nil
+}
+
+// Remove deletes file in package pool returns its size
+func (pool *PackagePool) Remove(path string) (size int64, err error) {
+	pool.Lock()
+	defer pool.Unlock()
+
+	path = filepath.Join(pool.rootPath, path)
+
+	info, err := os.Stat(path)
+	if err != nil {
+		return 0, err
+	}
+
+	err = os.Remove(path)
+	return info.Size(), err
+}
+
+// Import copies file into package pool
+func (pool *PackagePool) Import(path string, hashMD5 string) error {
+	pool.Lock()
+	defer pool.Unlock()
+
+	source, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer source.Close()
+
+	sourceInfo, err := source.Stat()
+	if err != nil {
+		return err
+	}
+
+	poolPath, err := pool.Path(path, hashMD5)
+	if err != nil {
+		return err
+	}
+
+	targetInfo, err := os.Stat(poolPath)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			// unable to stat target location?
+			return err
+		}
+	} else {
+		// target already exists
+		if targetInfo.Size() != sourceInfo.Size() {
+			// trying to overwrite file?
+			return fmt.Errorf("unable to import into pool: file %s already exists", poolPath)
+		}
+
+		// assume that target is already there
+		return nil
+	}
+
+	// create subdirs as necessary
+	err = os.MkdirAll(filepath.Dir(poolPath), 0777)
+	if err != nil {
+		return err
+	}
+
+	target, err := os.Create(poolPath)
+	if err != nil {
+		return err
+	}
+	defer target.Close()
+
+	_, err = io.Copy(target, source)
+
+	return err
+}