Implement Read Only mode

lib/storage/fs.go

@@ -0,0 +1,42 @@
+package storage
+
+import (
+	p "path"
+
+	"io"
+	"os"
+)
+
+type fsStore struct {
+	path string
+}
+
+func (st *fsStore) Create(id string, name string) (io.WriteCloser, error) {
+	path := idPath(st.path, id)
+	err := os.MkdirAll(path, os.ModePerm)
+	if err != nil {
+		return nil, err
+	}
+
+	return os.Create(p.Join(path, name))
+}
+
+func (st *fsStore) Store(id string, file io.Reader, name string) (size int64, err error) {
+	dest, err := st.Create(id, name)
+	if err != nil {
+		return 0, err
+	}
+	defer dest.Close()
+
+	return io.Copy(dest, file)
+}
+
+func (st *fsStore) Get(id string, name string) (File, error) {
+	path := idPath(st.path, id)
+	return os.Open(p.Join(path, name))
+}
+
+func (st *fsStore) Delete(id string) error {
+	path := idPath(st.path, id)
+	return os.RemoveAll(path)
+}

lib/storage/ro.go

@@ -0,0 +1,26 @@
+package storage
+
+import (
+	"errors"
+	"io"
+)
+
+type roStore struct {
+	store Store
+}
+
+func (st *roStore) Create(id string, name string) (io.WriteCloser, error) {
+	return nil, errors.New("Can't create, RO storage")
+}
+
+func (st *roStore) Store(id string, file io.Reader, name string) (size int64, err error) {
+	return 0, errors.New("Can't store, RO storage")
+}
+
+func (st *roStore) Get(id string, name string) (File, error) {
+	return st.store.Get(id, name)
+}
+
+func (st *roStore) Delete(id string) error {
+	return errors.New("Can't delete, RO storage")
+}

lib/storage/storage.go

@@ -1,14 +1,15 @@
 package storage
 
 import (
-	p "path"
-
 	"io"
 	"os"
 )
 
-type Store struct {
-	path string
+type Store interface {
+	Create(id string, name string) (io.WriteCloser, error)
+	Store(id string, file io.Reader, name string) (size int64, err error)
+	Get(id string, name string) (File, error)
+	Delete(id string) error
 }
 
 type File interface {
@@ -17,8 +18,8 @@ type File interface {
 	Stat() (fi os.FileInfo, err error)
 }
 
-func Init(path string) (*Store, error) {
-	st := new(Store)
+func Init(path string) (Store, error) {
+	st := new(fsStore)
 	st.path = path
 
 	_, err := os.Stat(path)
@@ -28,36 +29,6 @@ func Init(path string) (*Store, error) {
 	return st, err
 }
 
-func (st *Store) Create(id string, name string) (io.WriteCloser, error) {
-	path := idPath(st.path, id)
-	err := os.MkdirAll(path, os.ModePerm)
-	if err != nil {
-		return nil, err
-	}
-
-	return os.Create(p.Join(path, name))
-}
-
-func (st *Store) Store(id string, file io.Reader, name string) (size int64, err error) {
-	dest, err := st.Create(id, name)
-	if err != nil {
-		return 0, err
-	}
-	defer dest.Close()
-
-	return io.Copy(dest, file)
-}
-
-func (st *Store) Get(id string, name string) (File, error) {
-	path := idPath(st.path, id)
-	return os.Open(p.Join(path, name))
-}
-
-func (st *Store) Delete(id string) error {
-	path := idPath(st.path, id)
-	return os.RemoveAll(path)
-}
-
-func (st *Store) del() {
-	os.RemoveAll(st.path)
+func RO(st Store) Store {
+	return &roStore{st}
 }

lib/storage/storage_test.go

@@ -25,11 +25,11 @@ const (
 )
 
 func TestInit(t *testing.T) {
-	st, err := Init(test_path)
+	_, err := Init(test_path)
 	if err != nil {
 		t.Fatal("An error ocurred initializing the store =>", err)
 	}
-	defer st.del()
+	defer del()
 
 	info, err := os.Stat(test_path)
 	if err != nil {
@@ -50,7 +50,7 @@ func TestInit(t *testing.T) {
 
 func TestStore(t *testing.T) {
 	st, err := Init(test_path)
-	defer st.del()
+	defer del()
 
 	_, err = st.Store(test_id, strings.NewReader(test_book), "epub")
 	if err != nil {
@@ -72,7 +72,7 @@ func TestStore(t *testing.T) {
 
 func TestCreate(t *testing.T) {
 	st, err := Init(test_path)
-	defer st.del()
+	defer del()
 
 	f, err := st.Create(test_id, "img")
 	if err != nil {
@@ -95,7 +95,7 @@ func TestCreate(t *testing.T) {
 
 func TestDelete(t *testing.T) {
 	st, err := Init(test_path)
-	defer st.del()
+	defer del()
 
 	_, err = st.Store(test_id, strings.NewReader(test_book), "epub")
 	if err != nil {
@@ -111,3 +111,7 @@ func TestDelete(t *testing.T) {
 		t.Fatal("Retrieve book without error.")
 	}
 }
+
+func del() {
+	os.RemoveAll(test_path)
+}