Create simple alternate link plugin

We need a simple js script that enables usage of alternate html links. Use case: We want to add a link like to [login to view URL] but we want to use the data-href attribute to define the target URL like this <a href="#" data-href="[login to view URL]"></a> The requested script is supposed to look at the data-href attribute of all links in the document and if data-href is defined assign the value to the href attribute. In best case this is delivered both as a drop in script + as a simple activate and forget Wordpress plugin without settings page.