gistfile1.py

@blueprint.route('/<library_id>/upload', methods=['GET', 'POST'], auth=auth.admin)
@render_html()
def upload(library_id):
    try:
        library = m.Library.objects.get(id=library_id)
    except m.DoesNotExist:
        abort(404)

    class Form(IForm):
        name = wtf.TextField(_('Item name'), [wtf.Required(), wtf.Length(max=80)])
        file = wtf.FileField(_('Document'), [wtf.Required()])

        def validate_file(form, field):
            if field.data and field.data.content_type != 'application/pdf':
                raise wtf.ValidationError(_("File must be a PDF"))

    form = Form()

    if form.validate_on_submit():
        file = request.files[form.file.name]

        li         = m.LibraryItem()
        li.name    = form.name.data
        li.library = library
        li.document.put(
            request.files[form.file.name].read(),
            content_type = file.content_type,
            filename     = file.filename
        )
        li.save()

        flask.flash(_("Document uploaded"))
        return redirect(url_for('.read', library_id=library_id))

    return dict(form=form)