add(store): import storage layer and tests

store/.gitignore

@@ -0,0 +1 @@
+/test

store/interfaces.go

@@ -0,0 +1,23 @@
+package store
+
+import "io"
+
+type (
+	store struct {
+		namespace string
+
+		originalFn func(id uint64, ext string) string
+		previewFn  func(id uint64, ext string) string
+	}
+
+	Store interface {
+		Namespace() string
+
+		Original(id uint64, ext string) string
+		Preview(id uint64, ext string) string
+
+		Save(filename string, contents io.Reader) error
+		Remove(filename string) error
+		Open(filename string) (io.Reader, error)
+	}
+)

store/store.go

@@ -0,0 +1,75 @@
+package store
+
+import (
+	"fmt"
+	"io"
+	"path"
+
+	"github.com/spf13/afero"
+	"github.com/pkg/errors"
+)
+
+func New(namespace string) (Store, error) {
+	return &store{
+		namespace: namespace,
+		originalFn: func(id uint64, ext string) string {
+			return fmt.Sprintf("%d.%s", id, ext)
+		},
+		previewFn: func(id uint64, ext string) string {
+			return fmt.Sprintf("%d_preview.%s", id, ext)
+		},
+	}, nil
+}
+
+func (s *store) Namespace() string {
+	return s.namespace
+}
+
+func (s *store) check(filename string) error {
+	if filename[:len(s.namespace)+1] != s.namespace + "/" {
+		return errors.Errorf("Invalid namespace when trying to store file: %s (for %s)", filename, s.namespace)
+	}
+	return nil
+}
+
+func (s *store) Original(id uint64, ext string) string {
+	return path.Join(s.namespace, s.originalFn(id, ext))
+}
+
+func (s *store) Preview(id uint64, ext string) string {
+	return path.Join(s.namespace, s.previewFn(id, ext))
+}
+
+func (s *store) Save(filename string, contents io.Reader) error {
+	// check filename for validity
+	if err := s.check(filename); err != nil {
+		return err
+	}
+
+	folder := path.Dir(filename)
+
+	fs := afero.NewOsFs()
+	fs.MkdirAll(folder, 0755)
+
+	return afero.WriteReader(fs, filename, contents)
+}
+
+func (s *store) Remove(filename string) error {
+	// check filename for validity
+	if err := s.check(filename); err != nil {
+		return err
+	}
+
+	fs := afero.NewOsFs()
+	return fs.Remove(filename)
+}
+
+func (s *store) Open(filename string) (io.Reader, error) {
+	// check filename for validity
+	if err := s.check(filename); err != nil {
+		return nil, err
+	}
+
+	fs := afero.NewOsFs()
+	return fs.Open(filename)
+}

store/store_test.go

@@ -0,0 +1,72 @@
+package store_test
+
+import (
+	"io"
+	"bytes"
+	"testing"
+
+	"github.com/crusttech/crust/store"
+)
+
+func TestStore(t *testing.T) {
+	assert := func(ok bool, format string, params ...interface{}) {
+		if !ok {
+			t.Fatalf(format, params...)
+		}
+	}
+	readerToString := func(r io.Reader) string {
+		b := new(bytes.Buffer)
+		b.ReadFrom(r)
+		return b.String()
+	}
+
+	store, err := store.New("test")
+	assert(err == nil, "Unexpected error when creating store: %+v", err)
+	assert(store != nil, "Expected non-nil return for new store")
+	assert(store.Namespace() == "test", "Unexpected store namespace: test != %s", store.Namespace())
+
+	{
+		fn := store.Original(123, "jpg")
+		expected := "test/123.jpg"
+		assert(fn == expected, "Unexpected filename returned: %s != %s", expected, fn)
+	}
+
+	{
+		fn := store.Preview(123, "jpg")
+		expected := "test/123_preview.jpg"
+		assert(fn == expected, "Unexpected filename returned: %s != %s", expected, fn)
+	}
+
+	// write a file
+	{
+		buf := bytes.NewBuffer([]byte("This is a testing buffer"))
+		err := store.Save("test/123.jpg", buf)
+		assert(err == nil, "Error saving file, %+v", err)
+
+		err = store.Save("test123/123.jpg", buf)
+		assert(err != nil, "Expected error when saving file outside of namespace")
+	}
+
+	// read a file
+	{
+		buf, err := store.Open("test/123.jpg")
+		assert(err == nil, "Unexpected error when reading file: %+v", err)
+		s := readerToString(buf)
+		assert(s == "This is a testing buffer", "Unexpected response when reading file: %s", s)
+
+		_, err = store.Open("test/1234.jpg")
+		assert(err != nil, "Expected error when opening non-existent file")
+		_, err = store.Open("test123/123.jpg")
+		assert(err != nil, "Expected error when opening file outside of namespace")
+	}
+
+	// delete a file
+	{
+		err := store.Remove("test/123.jpg")
+		assert(err == nil, "Unexpected error when removing file: %+v", err)
+		err = store.Remove("test/123.jpg")
+		assert(err != nil, "Expected error when removing missing file")
+		err = store.Remove("test123/123.jpg")
+		assert(err != nil, "Expected error when deleting file outside of namespace")
+	}
+}