A build hook for shadow-cljs that

1. adds md5 hashes to the filenames of your static assets and
2. uses these filenames in your index.html.

This allows you to permit caching of your static assets, without the risk of users ever seeing outdated versions due to caching. Do not allow caching of index.html itself, however.

First, include [com.github.ljpengelen/shadow-cljs-hash-assets-hook "x.y.z"] as a dependency in the shadow-cljs.edn file of your project. The latest version is shown in the badge below.

Second, configure the build hook in your shadow-cljs.edn as follows:

{...
 :builds {:app {:target :browser
                ...
                :build-hooks [(shadow-cljs-hash-assets-hook/hash-assets! {:source-root "public"
                                                                          :target-root "dist"
                                                                          :index "index.html"
                                                                          :files ["css/site.css" "js/app.js"]
                                                                          :release-mode-only? true})]
                ...}}}

Then, build your app for production:

$ npx shadow-cljs release app

For the given configuration, this will calculate the md5 hashes of public/css/site.css and public/js/app.js, and place copies of these files with the corresponding hashes in their filename into dist/css/site-<hash>.css and dist/js/app-<hash>.js. Additionally, it will copy public/index.html into dist/index.html, with all references to the original files replaced by their renamed counterparts.

Because the configuration option :release-mode-only? is set to true, the above only happens when creating release builds. Set its value to false if you always want to hash assets.

MIT