[SalesForce] How to include images from static resources in lightning components used in communities

If its just a single file (so there are no issues with order of loading as this code loads the JavaScript asynchronously) you can work out the URL in JavaScript like this:

<script>
(function() {
    var script = document.createElement('script');
    script.src = '/community-name/resource/'
            + Date.now()
            + '/MyStaticResource/js/some-code.js';
    document.head.appendChild(script);
})();
</script>

Using the current date timestamp ensures the latest version of the static resource is obtained. That is the technique used in this sample AngularJs app, though there the JavaScript would only be requested, cached and used once per application session. But for your use, the JavaScript would be requested and cached every time a page is opened.

If your present system works well, probably better to stick to it than use the above.

We need to add required files under assets to access them in site.com. Seems like we can't directly use static resource from salesforce.

Manage --> Administration --> Go to site.com studio --> Assets --> import

After importing script files, we can refer them as below:

<ltng:require scripts="/Jquery.js"/>