I'm struggling on figuring out how to use angular-summernote callback on-image-upload.

The code in my view:

```
<summernote data-editable="editable" data-on-image-upload="imageUpload(files, editor)"></summernote>

```

And the imageUplaod function:

```
$scope.imageUpload = function(files, editor) {
    console.log(files);  // FileList
    console.log(editor);  // undefined
    console.log($scope.editable); // undefined
};

```

And the image is not inserted into the editor.
I have tried googling for the implementation example on the imageUpload, but find null. Can anyone show me how to do it?