diff --git a/server/app/files_test.go b/server/app/files_test.go
new file mode 100644
index 000000000..099d573aa
--- /dev/null
+++ b/server/app/files_test.go
@@ -0,0 +1,250 @@
+package app
+
+import (
+	"io"
+	"strings"
+	"testing"
+
+	"github.com/mattermost/mattermost-server/v6/plugin/plugintest/mock"
+	"github.com/mattermost/mattermost-server/v6/shared/filestore"
+	"github.com/mattermost/mattermost-server/v6/shared/filestore/mocks"
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	testFileName = "temp-file-name"
+	testRootID   = "test-root-id"
+	testFilePath = "1/test-root-id/temp-file-name"
+)
+
+type TestError struct{}
+
+func (err *TestError) Error() string { return "Mocked File backend error" }
+
+func TestGetFileReader(t *testing.T) {
+	th, _ := SetupTestHelper(t)
+	mockedReadCloseSeek := &mocks.ReadCloseSeeker{}
+	t.Run("should get file reader from filestore successfully", func(t *testing.T) {
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		readerFunc := func(path string) filestore.ReadCloseSeeker {
+			return mockedReadCloseSeek
+		}
+
+		readerErrorFunc := func(path string) error {
+			return nil
+		}
+
+		fileExistsFunc := func(path string) bool {
+			return true
+		}
+
+		fileExistsErrorFunc := func(path string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("Reader", testFilePath).Return(readerFunc, readerErrorFunc)
+		mockedFileBackend.On("FileExists", testFilePath).Return(fileExistsFunc, fileExistsErrorFunc)
+		actual, _ := th.App.GetFileReader("1", testRootID, testFileName)
+		assert.Equal(t, mockedReadCloseSeek, actual)
+	})
+
+	t.Run("should get error from filestore when file exists return error", func(t *testing.T) {
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		mockedError := &TestError{}
+		readerFunc := func(path string) filestore.ReadCloseSeeker {
+			return mockedReadCloseSeek
+		}
+
+		readerErrorFunc := func(path string) error {
+			return nil
+		}
+
+		fileExistsFunc := func(path string) bool {
+			return false
+		}
+
+		fileExistsErrorFunc := func(path string) error {
+			return mockedError
+		}
+
+		mockedFileBackend.On("Reader", testFilePath).Return(readerFunc, readerErrorFunc)
+		mockedFileBackend.On("FileExists", testFilePath).Return(fileExistsFunc, fileExistsErrorFunc)
+		actual, err := th.App.GetFileReader("1", testRootID, testFileName)
+		assert.Error(t, err, mockedError)
+		assert.Nil(t, actual)
+	})
+
+	t.Run("should return error, if get reader from file backend returns error", func(t *testing.T) {
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		mockedError := &TestError{}
+		readerFunc := func(path string) filestore.ReadCloseSeeker {
+			return nil
+		}
+
+		readerErrorFunc := func(path string) error {
+			return mockedError
+		}
+
+		fileExistsFunc := func(path string) bool {
+			return false
+		}
+
+		fileExistsErrorFunc := func(path string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("Reader", testFilePath).Return(readerFunc, readerErrorFunc)
+		mockedFileBackend.On("FileExists", testFilePath).Return(fileExistsFunc, fileExistsErrorFunc)
+		actual, err := th.App.GetFileReader("1", testRootID, testFileName)
+		assert.Error(t, err, mockedError)
+		assert.Nil(t, actual)
+	})
+
+	t.Run("should move file from old filepath to new filepath, if file doesnot exists in new filepath and workspace id is 0", func(t *testing.T) {
+		filePath := "0/test-root-id/temp-file-name"
+		workspaceid := "0"
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		readerFunc := func(path string) filestore.ReadCloseSeeker {
+			return mockedReadCloseSeek
+		}
+
+		readerErrorFunc := func(path string) error {
+			return nil
+		}
+
+		fileExistsFunc := func(path string) bool {
+			// return true for old path
+			return path == testFileName
+		}
+
+		fileExistsErrorFunc := func(path string) error {
+			return nil
+		}
+
+		moveFileFunc := func(oldFileName, newFileName string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("FileExists", filePath).Return(fileExistsFunc, fileExistsErrorFunc)
+		mockedFileBackend.On("FileExists", testFileName).Return(fileExistsFunc, fileExistsErrorFunc)
+		mockedFileBackend.On("MoveFile", testFileName, filePath).Return(moveFileFunc)
+		mockedFileBackend.On("Reader", filePath).Return(readerFunc, readerErrorFunc)
+
+		actual, _ := th.App.GetFileReader(workspaceid, testRootID, testFileName)
+		assert.Equal(t, mockedReadCloseSeek, actual)
+	})
+
+	t.Run("should return file reader, if file doesnot exists in new filepath and old file path", func(t *testing.T) {
+		filePath := "0/test-root-id/temp-file-name"
+		fileName := testFileName
+		workspaceid := "0"
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		readerFunc := func(path string) filestore.ReadCloseSeeker {
+			return mockedReadCloseSeek
+		}
+
+		readerErrorFunc := func(path string) error {
+			return nil
+		}
+
+		fileExistsFunc := func(path string) bool {
+			// return true for old path
+			return false
+		}
+
+		fileExistsErrorFunc := func(path string) error {
+			return nil
+		}
+
+		moveFileFunc := func(oldFileName, newFileName string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("FileExists", filePath).Return(fileExistsFunc, fileExistsErrorFunc)
+		mockedFileBackend.On("FileExists", testFileName).Return(fileExistsFunc, fileExistsErrorFunc)
+		mockedFileBackend.On("MoveFile", fileName, filePath).Return(moveFileFunc)
+		mockedFileBackend.On("Reader", filePath).Return(readerFunc, readerErrorFunc)
+
+		actual, _ := th.App.GetFileReader(workspaceid, testRootID, testFileName)
+		assert.Equal(t, mockedReadCloseSeek, actual)
+	})
+}
+
+func TestSaveFile(t *testing.T) {
+	th, _ := SetupTestHelper(t)
+	mockedReadCloseSeek := &mocks.ReadCloseSeeker{}
+	t.Run("should save file to file store using file backend", func(t *testing.T) {
+		fileName := "temp-file-name.txt"
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+
+		writeFileFunc := func(reader io.Reader, path string) int64 {
+			paths := strings.Split(path, "/")
+			assert.Equal(t, "1", paths[0])
+			assert.Equal(t, testRootID, paths[1])
+			fileName = paths[2]
+			return int64(10)
+		}
+
+		writeFileErrorFunc := func(reader io.Reader, filePath string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("WriteFile", mockedReadCloseSeek, mock.Anything).Return(writeFileFunc, writeFileErrorFunc)
+		actual, err := th.App.SaveFile(mockedReadCloseSeek, "1", testRootID, fileName)
+		assert.Equal(t, fileName, actual)
+		assert.Nil(t, err)
+	})
+
+	t.Run("should save .jpeg file as jpg file to file store using file backend", func(t *testing.T) {
+		fileName := "temp-file-name.jpeg"
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+
+		writeFileFunc := func(reader io.Reader, path string) int64 {
+			paths := strings.Split(path, "/")
+			assert.Equal(t, "1", paths[0])
+			assert.Equal(t, "test-root-id", paths[1])
+			assert.Equal(t, "jpg", strings.Split(paths[2], ".")[1])
+			return int64(10)
+		}
+
+		writeFileErrorFunc := func(reader io.Reader, filePath string) error {
+			return nil
+		}
+
+		mockedFileBackend.On("WriteFile", mockedReadCloseSeek, mock.Anything).Return(writeFileFunc, writeFileErrorFunc)
+		actual, err := th.App.SaveFile(mockedReadCloseSeek, "1", "test-root-id", fileName)
+		assert.Nil(t, err)
+		assert.NotNil(t, actual)
+	})
+
+	t.Run("should return error when fileBackend.WriteFile returns error", func(t *testing.T) {
+		fileName := "temp-file-name.jpeg"
+		mockedFileBackend := &mocks.FileBackend{}
+		th.App.filesBackend = mockedFileBackend
+		mockedError := &TestError{}
+
+		writeFileFunc := func(reader io.Reader, path string) int64 {
+			paths := strings.Split(path, "/")
+			assert.Equal(t, "1", paths[0])
+			assert.Equal(t, "test-root-id", paths[1])
+			assert.Equal(t, "jpg", strings.Split(paths[2], ".")[1])
+			return int64(10)
+		}
+
+		writeFileErrorFunc := func(reader io.Reader, filePath string) error {
+			return mockedError
+		}
+
+		mockedFileBackend.On("WriteFile", mockedReadCloseSeek, mock.Anything).Return(writeFileFunc, writeFileErrorFunc)
+		actual, err := th.App.SaveFile(mockedReadCloseSeek, "1", "test-root-id", fileName)
+		assert.Equal(t, "", actual)
+		assert.Equal(t, "unable to store the file in the files storage: Mocked File backend error", err.Error())
+	})
+}