app/imageoper, app/maindb: one image - one arch; app/storage: blob to name subdir

app/storage/file.go

@@ -0,0 +1,133 @@
+/*
+ * Copyright 2026 Oleg Borodin <onborodin@gmail.com>
+ *
+ * This work is published and licensed under a Creative Commons
+ * Attribution-NonCommercial-NoDerivatives 4.0 International License.
+ *
+ * Distribution of this work is permitted, but commercial use and
+ * modifications are strictly prohibited.
+ */
+package storage
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"mstore/pkg/auxuuid"
+)
+
+const (
+	sha256prefix = "sha256:"
+	fileSubdir   = "files"
+	tmpSubdir    = "tmps"
+)
+
+func (store *Storage) makeCollecionpath(collection string) string {
+	return filepath.Join(store.basepath, fileSubdir, collection)
+}
+
+func (store *Storage) makeFilepath(collection, filename string) string {
+	return filepath.Join(store.basepath, fileSubdir, collection, filename)
+}
+
+func (store *Storage) makeTmppath(tmpName string) string {
+	return filepath.Join(store.basepath, tmpSubdir, tmpName)
+}
+
+func (store *Storage) makeTmpsubdir() string {
+	return filepath.Join(store.basepath, tmpSubdir)
+}
+
+func (store *Storage) makeFilesubdir(collection, filename string) string {
+	return filepath.Join(store.basepath, fileSubdir)
+}
+
+func (store *Storage) GetFileReader(collection, filename string) (io.ReadCloser, error) {
+	var err error
+	var res io.ReadCloser
+
+	filename = store.makeFilepath(collection, filename)
+	file, err := os.OpenFile(filename, os.O_RDONLY, 0)
+	if err != nil {
+		return res, err
+	}
+	res = file
+	return res, err
+}
+
+func (store *Storage) WriteTempFile(source io.Reader) (string, int64, string, error) {
+	var err error
+	var size int64
+	var csum string
+
+	tmpName := fmt.Sprintf("%s.tmp", auxuuid.NewUUID())
+	tmpPath := store.makeTmppath(tmpName)
+
+	tmpdirpath := store.makeTmpsubdir()
+	err = os.MkdirAll(tmpdirpath, 0750)
+	if err != nil {
+		return tmpName, size, csum, err
+	}
+
+	file, err := os.OpenFile(tmpPath, os.O_WRONLY|os.O_CREATE, 0640)
+	if err != nil {
+		return tmpName, size, csum, err
+	}
+	defer file.Close()
+
+	hasher := NewHasher()
+	mWriter := io.MultiWriter(file, hasher.Writer())
+	size, err = io.Copy(mWriter, source)
+	if err != nil {
+		return tmpName, size, csum, err
+	}
+	csum = hasher.Hex()
+
+	return tmpName, size, csum, err
+}
+
+func (store *Storage) HardlinkFile(tmpName, collection, filename string) error {
+	var err error
+
+	dirname := store.makeCollecionpath(collection)
+	_, err = os.Stat(dirname)
+	if os.IsNotExist(err) {
+		err = os.MkdirAll(dirname, 0750)
+		if err != nil {
+			return err
+		}
+	}
+	if err != nil {
+		return err
+	}
+	filename = store.makeFilepath(collection, filename)
+	_, err = os.Stat(dirname)
+	if err == nil {
+		os.Remove(filename) // TODO: safe removing
+	}
+	tmpName = store.makeTmppath(tmpName)
+	err = os.Link(tmpName, filename)
+	if err != nil {
+		return err
+	}
+	err = os.Remove(tmpName)
+	if err != nil {
+		return err
+	}
+	return err
+}
+
+func (store *Storage) DeleteFile(collection, filename string) error {
+	var err error
+	filename = store.makeFilepath(collection, filename)
+	err = os.Remove(filename)
+	if err != nil {
+		return err
+	}
+	// TODO: clean removing
+	dirname := store.makeCollecionpath(collection)
+	os.RemoveAll(dirname)
+	return err
+}