rename package

pkg/thumbnail/storage/filesystem.go

@@ -0,0 +1,82 @@
+package storage
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+
+	"github.com/owncloud/ocis-pkg/v2/log"
+	"github.com/owncloud/ocis-thumbnails/pkg/config"
+)
+
+// NewFileSystemStorage creates a new instanz of FileSystem
+func NewFileSystemStorage(cfg config.FileSystemStorage, logger log.Logger) FileSystem {
+	return FileSystem{
+		dir:    cfg.RootDirectory,
+		logger: logger,
+	}
+}
+
+// FileSystem represents a storage for the thumbnails using the local file system.
+type FileSystem struct {
+	dir    string
+	logger log.Logger
+}
+
+// Get loads the image from the file system.
+func (s FileSystem) Get(key string) []byte {
+	content, err := ioutil.ReadFile(filepath.Join(s.dir, key))
+	if err != nil {
+		s.logger.Warn().Err(err).Msgf("could not read file %s", key)
+		return nil
+	}
+
+	return content
+}
+
+// Set writes the image to the file system.
+func (s FileSystem) Set(key string, img []byte) error {
+	path := filepath.Join(s.dir, key)
+	dir := filepath.Dir(path)
+	if err := os.MkdirAll(dir, 0700); err != nil {
+		return fmt.Errorf("error while creating directory %s", dir)
+	}
+
+	f, err := os.Create(path)
+	if err != nil {
+		return fmt.Errorf("could not create file \"%s\" error: %s", key, err.Error())
+	}
+	defer f.Close()
+	_, err = f.Write(img)
+	if err != nil {
+		return fmt.Errorf("could not write to file \"%s\" error: %s", key, err.Error())
+	}
+	return nil
+}
+
+// BuildKey generate the unique key for a thumbnail.
+// The key is structure as follows:
+//
+// <first two letters of etag>/<next two letters of etag>/<rest of etag>/<width>x<height>.<filetype>
+//
+// e.g. 97/9f/4c8db98f7b82e768ef478d3c8612/500x300.png
+//
+// The key also represents the path to the thumbnail in the filesystem under the configured root directory.
+func (s FileSystem) BuildKey(r Request) string {
+	etag := r.ETag
+	filetype := r.Types[0]
+	filename := r.Resolution.String() + "." + filetype
+
+	key := new(bytes.Buffer)
+	key.WriteString(etag[:2])
+	key.WriteRune('/')
+	key.WriteString(etag[2:4])
+	key.WriteRune('/')
+	key.WriteString(etag[4:])
+	key.WriteRune('/')
+	key.WriteString(filename)
+
+	return key.String()
+}