Factoring metadata out into seperate file

meta.go

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2015 Alex Yatskov <alex@foosoft.net>
+ * Author: Alex Yatskov <alex@foosoft.net>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+package main
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+type versionMetadata struct {
+	Deleted []string `json:"deleted"`
+	path    string
+}
+
+func newVersionMetadata(path string) (*versionMetadata, error) {
+	meta := &versionMetadata{path: path}
+	if err := meta.load(); err != nil {
+		return nil, err
+	}
+
+	return meta, nil
+}
+
+func (this *versionMetadata) filter(base string, nodes map[string]versionedNode) {
+	for _, delPath := range this.Deleted {
+		dir, file := filepath.Split(delPath)
+		if dir == base {
+			delete(nodes, file)
+		}
+	}
+}
+
+func (this *versionMetadata) load() error {
+	if _, err := os.Stat(this.path); os.IsNotExist(err) {
+		return nil
+	}
+
+	bytes, err := ioutil.ReadFile(this.path)
+	if err != nil {
+		return err
+	}
+
+	if err := json.Unmarshal(bytes, &this); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (this *versionMetadata) save() error {
+	js, err := json.Marshal(this)
+	if err != nil {
+		return err
+	}
+
+	return ioutil.WriteFile(this.path, js, 0644)
+}

version.go

@@ -24,7 +24,6 @@ package main
 
 import (
 	"bazil.org/fuse/fs"
-	"encoding/json"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -35,19 +34,6 @@ import (
 	"time"
 )
 
-type versionMetadata struct {
-	Deleted []string `json:"deleted"`
-}
-
-func (this *versionMetadata) filter(base string, nodes map[string]versionedNode) {
-	for _, delPath := range this.Deleted {
-		dir, file := filepath.Split(delPath)
-		if dir == base {
-			delete(nodes, file)
-		}
-	}
-}
-
 type versionedNode struct {
 	path string
 	info os.FileInfo
@@ -57,7 +43,7 @@ type version struct {
 	base      string
 	parent    *version
 	timestamp time.Time
-	meta      versionMetadata
+	meta      *versionMetadata
 	root      *versionedDir
 	inodeCnt  uint64
 }
@@ -83,7 +69,8 @@ func newVersion(base string, parent *version) (*version, error) {
 		parent:    parent,
 		timestamp: time.Unix(timeval, 0)}
 
-	if err := ver.loadMetadata(); err != nil {
+	ver.meta, err = newVersionMetadata(ver.metadataPath())
+	if err != nil {
 		return nil, err
 	}
 
@@ -166,32 +153,6 @@ func (this *version) resolve() error {
 	return this.buildDir("/", this.root)
 }
 
-func (this *version) loadMetadata() error {
-	if _, err := os.Stat(this.metadataPath()); os.IsNotExist(err) {
-		return nil
-	}
-
-	bytes, err := ioutil.ReadFile(this.metadataPath())
-	if err != nil {
-		return err
-	}
-
-	if err := json.Unmarshal(bytes, &this.meta); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-func (this *version) saveMetadata() error {
-	js, err := json.Marshal(this.meta)
-	if err != nil {
-		return err
-	}
-
-	return ioutil.WriteFile(this.metadataPath(), js, 0644)
-}
-
 func (this *version) metadataPath() string {
 	return filepath.Join(this.base, "meta.json")
 }