Implementation of File Exists Function; Delete FileInfos upon Permanent User Delete (#8958)

Check if file was deleted on FS

Warning message if file couldnt be removed

4 files changed, 49 insertions, 0 deletions

diff --git a/utils/file_backend.go b/utils/file_backend.go
index 9ed564592..368e1ba28 100644
--- a/utils/file_backend.go
+++ b/utils/file_backend.go
@@ -15,6 +15,7 @@ type FileBackend interface {
 
 	Reader(path string) (io.ReadCloser, *model.AppError)
 	ReadFile(path string) ([]byte, *model.AppError)
+	FileExists(path string) (bool, *model.AppError)
 	CopyFile(oldPath, newPath string) *model.AppError
 	MoveFile(oldPath, newPath string) *model.AppError
 	WriteFile(fr io.Reader, path string) (int64, *model.AppError)
diff --git a/utils/file_backend_local.go b/utils/file_backend_local.go
index ec0c657a7..681ab9234 100644
--- a/utils/file_backend_local.go
+++ b/utils/file_backend_local.go
@@ -49,6 +49,18 @@ func (b *LocalFileBackend) ReadFile(path string) ([]byte, *model.AppError) {
 	}
 }
 
+func (b *LocalFileBackend) FileExists(path string) (bool, *model.AppError) {
+	_, err := os.Stat(filepath.Join(b.directory, path))
+
+	if os.IsNotExist(err) {
+		return false, nil
+	} else if err == nil {
+		return true, nil
+	}
+
+	return false, model.NewAppError("ReadFile", "api.file.file_exists.exists_local.app_error", nil, err.Error(), http.StatusInternalServerError)
+}
+
 func (b *LocalFileBackend) CopyFile(oldPath, newPath string) *model.AppError {
 	if err := CopyFile(filepath.Join(b.directory, oldPath), filepath.Join(b.directory, newPath)); err != nil {
 		return model.NewAppError("copyFile", "api.file.move_file.rename.app_error", nil, err.Error(), http.StatusInternalServerError)
diff --git a/utils/file_backend_s3.go b/utils/file_backend_s3.go
index a0c46e5d3..dedcb2797 100644
--- a/utils/file_backend_s3.go
+++ b/utils/file_backend_s3.go
@@ -111,6 +111,25 @@ func (b *S3FileBackend) ReadFile(path string) ([]byte, *model.AppError) {
 	}
 }
 
+func (b *S3FileBackend) FileExists(path string) (bool, *model.AppError) {
+	s3Clnt, err := b.s3New()
+
+	if err != nil {
+		return false, model.NewAppError("FileExists", "api.file.file_exists.s3.app_error", nil, err.Error(), http.StatusInternalServerError)
+	}
+	_, err = s3Clnt.StatObject(b.bucket, path, s3.StatObjectOptions{})
+
+	if err == nil {
+		return true, nil
+	}
+
+	if err.(s3.ErrorResponse).Code == "NoSuchKey" {
+		return false, nil
+	}
+
+	return false, model.NewAppError("FileExists", "api.file.file_exists.s3.app_error", nil, err.Error(), http.StatusInternalServerError)
+}
+
 func (b *S3FileBackend) CopyFile(oldPath, newPath string) *model.AppError {
 	s3Clnt, err := b.s3New()
 	if err != nil {
diff --git a/utils/file_backend_test.go b/utils/file_backend_test.go
index 7f8265d73..f7ce7ca61 100644
--- a/utils/file_backend_test.go
+++ b/utils/file_backend_test.go
@@ -124,6 +124,23 @@ func (s *FileBackendTestSuite) TestReadWriteFileImage() {
 	s.EqualValues(readString, "testimage")
 }
 
+func (s *FileBackendTestSuite) TestFileExists() {
+	b := []byte("testimage")
+	path := "tests/" + model.NewId() + ".png"
+
+	_, err := s.backend.WriteFile(bytes.NewReader(b), path)
+	s.Nil(err)
+	defer s.backend.RemoveFile(path)
+
+	res, err := s.backend.FileExists(path)
+	s.Nil(err)
+	s.True(res)
+
+	res, err = s.backend.FileExists("tests/idontexist.png")
+	s.Nil(err)
+	s.False(res)
+}
+
 func (s *FileBackendTestSuite) TestCopyFile() {
 	b := []byte("test")
 	path1 := "tests/" + model.NewId()