See https://issues.liferay.com/browse/LPS-132149 for the LPS.
This is a manually crafted example based on a standard JS Toolkit React portlet project demonstrating how the Fat JAR feature could be implemented leveraging the current bundler 2.
This repo is a Yarn workspace for demonstration purposes (i.e: so that it can be built and deployed) but in the final image, only the fat-test project would be necessary (user side) because liferay-7.4-GA1 would be published by us.
-fat-test: this contains a React based portlet sample project as it would be seen by the user. -liferay-7.4-GA1: this contains a bundler preset with all necessary information to deploy a portlet to current liferay-portal (master).
Things worth noting:
1) The fat-test project is a portlet because I started the PoC based on the
current state of the JS Toolkit, but the use case for the Fat JAR feature is
(generally) not a portlet, but a Liferay extension project as those handled
by blade.
2) Per the point avoid, we can assume that, most of the times, the projects like
fat-test will be embedded a container Java project and that blade will be
used to manage those.
3) Even though liferay-7.4-GA1 is targeting the current master version of
liferay-portal I named it like that to show that we would have one of this
per released Liferay version.
4) Per 3 above, bundler presets like liferay-7.4-GA1 would really be the
equivalent of the fat JAR in the npm world.
I have tested that this works correctly in the current liferay-portal and that
it uses react from frontend-js-react-web.
Please read the commit history of the project to see the steps I made to configure the project and the decissions taken.
Finally, note that this can be directly implemented with the current version of the JS Toolkit (no need to change anything). However, we may want some minor modifications to be able to (for example):