I’m working on a project that allows friends to work out who owes cash to whom after a joint event: it’s called Kittysplit and is built in Java / Google App Engine.
Running the site through Google’s wonderful page speed insights tool resulted in this recommendation: “Leverage browser caching”.
Here’s what you need to do to implement caching for static files.
Add the following to appengine-web.xml (remembering to substitute the correct directory for /STATIC_DIR/).
<!-- Set a long cache expiration time for static files -->
<static-files>
<include path="/STATIC_DIR/**" expiration="365d"/>
<include path="/**.html">
</static-files>For some reason app engine does not serve static HTML files unless the second include is also present.
More information can be found here