Merge pull request #25 from keep-network/storage-dir-validation

Checking if a storage dir is readable and writable

Author: lukasz-zimnoch

pkg/persistence/disk_persistence.go

@@ -12,28 +12,25 @@ const (
 )
 
 // NewDiskHandle creates on-disk data persistence handle
-func NewDiskHandle(path string) Handle {
-	err := createDir(path, currentDir)
+func NewDiskHandle(path string) (Handle, error) {
+	err := checkStoragePermission(path)
 	if err != nil {
-		logger.Errorf(
-			"failed while creating directory [%v]: [%v]",
-			currentDir,
-			err,
-		)
+		return nil, err
+	}
+
+	err = createDir(path, currentDir)
+	if err != nil {
+		return nil, err
 	}
 
 	err = createDir(path, archiveDir)
 	if err != nil {
-		logger.Errorf(
-			"failed while creating directory [%v]: [%v]",
-			archiveDir,
-			err,
-		)
+		return nil, err
 	}
 
 	return &diskPersistence{
 		dataDir: path,
-	}
+	}, nil
 }
 
 type diskPersistence struct {
@@ -65,6 +62,22 @@ func (ds *diskPersistence) getStorageCurrentDirPath() string {
 	return fmt.Sprintf("%s/%s", ds.dataDir, currentDir)
 }
 
+func checkStoragePermission(dirBasePath string) error {
+	_, err := ioutil.ReadDir(dirBasePath)
+	if err != nil {
+		return fmt.Errorf("cannot read from the storage directory: [%v]", err)
+	}
+
+	tempFile, err := ioutil.TempFile(dirBasePath, "write-test.*.tmp")
+	if err != nil {
+		return fmt.Errorf("cannot write to the storage directory: [%v]", err)
+	}
+
+	defer os.RemoveAll(tempFile.Name())
+
+	return nil
+}
+
 func createDir(dirBasePath, newDirName string) error {
 	dirPath := fmt.Sprintf("%s/%s", dirBasePath, newDirName)
 	if _, err := os.Stat(dirPath); os.IsNotExist(err) {

pkg/persistence/disk_persistence_test.go

@@ -2,11 +2,13 @@ package persistence
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
+	"io/ioutil"
 	"os"
+	"strings"
 	"sync"
 	"testing"
-	"io/ioutil"
 )
 
 var (
@@ -24,6 +26,9 @@ var (
 
 	pathToCurrent = fmt.Sprintf("%s/%s", dataDir, dirCurrent)
 	pathToArchive = fmt.Sprintf("%s/%s", dataDir, dirArchive)
+
+	errExpectedRead  = errors.New("cannot read from the storage directory: ")
+	errExpectedWrite = errors.New("cannot write to the storage directory: ")
 )
 
 func TestMain(m *testing.M) {
@@ -34,7 +39,7 @@ func TestMain(m *testing.M) {
 }
 
 func TestDiskPersistence_Save(t *testing.T) {
-	diskPersistence := NewDiskHandle(dataDir)
+	diskPersistence, _ := NewDiskHandle(dataDir)
 	bytesToTest := []byte{115, 111, 109, 101, 10}
 
 	diskPersistence.Save(bytesToTest, dirName1, fileName11)
@@ -46,8 +51,30 @@ func TestDiskPersistence_Save(t *testing.T) {
 	}
 }
 
+func TestDiskPersistence_StoragePermission(t *testing.T) {
+	tempDir := "./data_storage"
+
+	err := os.Mkdir(tempDir, 0000) // d---------
+	if _, err := os.Stat(tempDir); os.IsNotExist(err) {
+		t.Fatalf("dir [%+v] was supposed to be created", tempDir)
+	}
+	defer os.RemoveAll(tempDir)
+
+	_, err = NewDiskHandle(tempDir)
+	if err == nil || !strings.Contains(err.Error(), errExpectedRead.Error()) {
+		t.Fatalf("error on read was supposed to be returned")
+	}
+
+	os.Chmod(tempDir, 0444) // dr--r--r
+
+	_, err = NewDiskHandle(tempDir)
+	if err == nil || !strings.Contains(err.Error(), errExpectedWrite.Error()) {
+		t.Fatalf("error on write was supposed to be returned")
+	}
+}
+
 func TestDiskPersistence_ReadAll(t *testing.T) {
-	diskPersistence := NewDiskHandle(dataDir)
+	diskPersistence, _ := NewDiskHandle(dataDir)
 
 	bytesToTest := []byte{115, 111, 109, 101, 10}
 	expectedBytes := [][]byte{bytesToTest, bytesToTest, bytesToTest}
@@ -110,7 +137,7 @@ func TestDiskPersistence_ReadAll(t *testing.T) {
 }
 
 func TestDiskPersistence_Archive(t *testing.T) {
-	diskPersistence := NewDiskHandle(dataDir)
+	diskPersistence, _ := NewDiskHandle(dataDir)
 
 	pathMoveFrom := fmt.Sprintf("%s/%s", pathToCurrent, dirName1)
 	pathMoveTo := fmt.Sprintf("%s/%s", pathToArchive, dirName1)
@@ -147,7 +174,7 @@ func TestDiskPersistence_Archive(t *testing.T) {
 }
 
 func TestDiskPersistence_AppendToArchive(t *testing.T) {
-	diskPersistence := NewDiskHandle(dataDir)
+	diskPersistence, _ := NewDiskHandle(dataDir)
 
 	pathMoveFrom := fmt.Sprintf("%s/%s", pathToCurrent, dirName1)
 	pathMoveTo := fmt.Sprintf("%s/%s", pathToArchive, dirName1)
@@ -157,11 +184,11 @@ func TestDiskPersistence_AppendToArchive(t *testing.T) {
 	diskPersistence.Save(bytesToTest, dirName1, fileName11)
 	diskPersistence.Save(bytesToTest, dirName1, fileName12)
 	diskPersistence.Archive(dirName1)
-	
+
 	diskPersistence.Save(bytesToTest, dirName1, "/file13")
 	diskPersistence.Save(bytesToTest, dirName1, "/file14")
 	diskPersistence.Archive(dirName1)
-	
+
 	if _, err := os.Stat(pathMoveFrom); !os.IsNotExist(err) {
 		t.Fatalf("Dir [%+v] was supposed to be removed", pathMoveFrom)
 	}
@@ -171,4 +198,4 @@ func TestDiskPersistence_AppendToArchive(t *testing.T) {
 		t.Fatalf("Number of all files was supposed to be [%+v]", 4)
 	}
 
-}
+}