vfs: Use fuse.Forget instead of cache TTL (#12)

* vfs: Use fuse.Forget instead of cache TTL

Signed-off-by: Xuanwo <github@xuanwo.io>

* Update docs

Signed-off-by: Xuanwo <github@xuanwo.io>

README.md

@@ -1,3 +1,15 @@
 # BeyondFS
 
-A high-performance, POSIX-ish File System based on [aos-dev/go-storage](https://github.com/aos-dev/go-storage).
+A high-performance, POSIX-ish File System based on [beyondstorage/go-storage](https://github.com/beyondstorage/go-storage).
+
+## Design
+
+- Only cache metadata
+- Sharable
+- POSIX-ish
+
+Refer to [RFC-5: BeyondFS Design](./docs/rfcs/5-beyond-fs-design.md) to know more. 
+
+## Current Status
+
+We are working on [implement a POSIX-ish file system that only caches metadata locally](https://github.com/beyondstorage/beyond-fs/issues/8)

fuse/hanwen/fs.go

@@ -166,6 +166,10 @@ func (fs *FS) Lookup(cancel <-chan struct{}, header *fuse.InHeader, name string,
 }
 
 func (fs *FS) Forget(nodeid, nlookup uint64) {
+	err := fs.fs.DeleteInodeByID(nodeid)
+	if err != nil {
+		fs.logger.Error("forget", zap.Error(err))
+	}
 }
 
 func (fs *FS) GetAttr(cancel <-chan struct{}, input *fuse.GetAttrIn, out *fuse.AttrOut) (code fuse.Status) {

meta/badger.go

@@ -2,7 +2,6 @@ package meta
 
 import (
 	"fmt"
-	"time"
 
 	"github.com/dgraph-io/badger/v3"
 )
@@ -38,7 +37,7 @@ func (db badgerDB) Get(key []byte) (value []byte, err error) {
 	return v.ValueCopy(nil)
 }
 
-func (db badgerDB) Set(key, value []byte, ttl time.Duration) (err error) {
+func (db badgerDB) Set(key, value []byte) (err error) {
 	txn := db.db.NewTransaction(true)
 	defer txn.Discard()
 
@@ -47,10 +46,6 @@ func (db badgerDB) Set(key, value []byte, ttl time.Duration) (err error) {
 		Value: value,
 	}
 
-	if ttl != 0 {
-		e.ExpiresAt = uint64(time.Now().Add(ttl).Unix())
-	}
-
 	err = txn.SetEntry(e)
 	if err != nil {
 		return err

meta/badger_bench_test.go

@@ -3,7 +3,6 @@ package meta
 import (
 	"bytes"
 	"testing"
-	"time"
 )
 
 func BenchmarkGet(b *testing.B) {
@@ -16,7 +15,7 @@ func BenchmarkGet(b *testing.B) {
 	key := bytes.Repeat([]byte{'a'}, 128)
 	value := bytes.Repeat([]byte{'a'}, 1024)
 
-	err = srv.Set(key, value, time.Hour)
+	err = srv.Set(key, value)
 	if err != nil {
 		b.Error(err)
 		return
@@ -38,6 +37,6 @@ func BenchmarkSet(b *testing.B) {
 	value := bytes.Repeat([]byte{'a'}, 1024)
 
 	for i := 0; i < b.N; i++ {
-		_ = srv.Set(key, value, time.Hour)
+		_ = srv.Set(key, value)
 	}
 }

meta/meta.go

@@ -1,13 +1,11 @@
 package meta
 
-import "time"
-
 type Service interface {
 	// Get will get the value with specified key.
 	//
 	// value will be nil if key not found.
 	Get(key []byte) (value []byte, err error)
-	Set(key, value []byte, ttl time.Duration) (err error)
+	Set(key, value []byte) (err error)
 	Delete(key []byte) (err error)
 	PrefixDelete(prefix []byte) (err error)
 	Scan(prefix []byte) Iterator

vfs/dir.go

@@ -5,7 +5,6 @@ import (
 	"github.com/beyondstorage/beyond-fs/meta"
 	"github.com/beyondstorage/go-storage/v4/types"
 	"sync"
-	"time"
 )
 
 type dirHandleMap struct {
@@ -58,8 +57,9 @@ func (dh *DirHandle) Next() (ino *Inode, err error) {
 		return nil, err
 	}
 
+	// TODO: maybe we can read data from cache instead.
 	ino = newInode(dh.ino.ID, o)
-	err = dh.fs.SetInode(ino, time.Hour)
+	err = dh.fs.SetInode(ino)
 	if err != nil {
 		return
 	}

vfs/fs.go

@@ -2,14 +2,13 @@ package vfs
 
 import (
 	"fmt"
-	"go.uber.org/atomic"
-	"time"
 
 	_ "github.com/beyondstorage/go-service-fs/v3"
 	_ "github.com/beyondstorage/go-service-s3/v2"
 	"github.com/beyondstorage/go-storage/v4/pairs"
 	"github.com/beyondstorage/go-storage/v4/services"
 	"github.com/beyondstorage/go-storage/v4/types"
+	"go.uber.org/atomic"
 	"go.uber.org/zap"
 
 	"github.com/beyondstorage/beyond-fs/meta"
@@ -65,7 +64,7 @@ func NewFS(cfg *Config) (fs *FS, err error) {
 	o.ID = store.Metadata().WorkDir
 	o.Path = ""
 	o.Mode = types.ModeDir
-	err = fs.SetInode(newInode(1, o), 0)
+	err = fs.SetInode(newInode(1, o))
 	if err != nil {
 		return nil, err
 	}
@@ -85,6 +84,10 @@ func (fs *FS) Delete(parent uint64, name string) (err error) {
 	if err != nil {
 		return
 	}
+	err = fs.DeleteEntry(parent, name)
+	if err != nil {
+		return
+	}
 	return
 }
 
@@ -118,13 +121,13 @@ func (fs *FS) DeleteDirHandle(dhid uint64) (err error) {
 	return nil
 }
 
-func (fs *FS) SetInode(ino *Inode, ttl time.Duration) (err error) {
+func (fs *FS) SetInode(ino *Inode) (err error) {
 	bs, err := ino.MarshalMsg(nil)
 	if err != nil {
 		return fmt.Errorf("marshal inode: %w", err)
 	}
 
-	err = fs.meta.Set(meta.InodeKey(ino.ID), bs, ttl)
+	err = fs.meta.Set(meta.InodeKey(ino.ID), bs)
 	if err != nil {
 		return fmt.Errorf("set inode: %w", err)
 	}
@@ -132,7 +135,7 @@ func (fs *FS) SetInode(ino *Inode, ttl time.Duration) (err error) {
 		// Don't set entry key for root directory.
 		return nil
 	}
-	err = fs.meta.Set(meta.EntryKey(ino.ParentID, ino.Name), bs, ttl)
+	err = fs.meta.Set(meta.EntryKey(ino.ParentID, ino.Name), bs)
 	if err != nil {
 		return fmt.Errorf("set entry: %w", err)
 	}
@@ -162,7 +165,11 @@ func (fs *FS) DeleteInode(ino *Inode) (err error) {
 	if err != nil {
 		return fmt.Errorf("del inode: %w", err)
 	}
-	err = fs.meta.Delete(meta.EntryKey(ino.ParentID, ino.Name))
+	return
+}
+
+func (fs *FS) DeleteInodeByID(id uint64) (err error) {
+	err = fs.meta.Delete(meta.InodeKey(id))
 	if err != nil {
 		return fmt.Errorf("del inode: %w", err)
 	}
@@ -186,3 +193,11 @@ func (fs *FS) GetEntry(parent uint64, name string) (ino *Inode, err error) {
 	}
 	return
 }
+
+func (fs *FS) DeleteEntry(parent uint64, name string) (err error) {
+	err = fs.meta.Delete(meta.EntryKey(parent, name))
+	if err != nil {
+		return fmt.Errorf("del inode: %w", err)
+	}
+	return
+}