Cache Busting

When you serve front-end assets through a CDN, these assets are often cached. To guarantee that your users receive the latest version of assets, clearing your CDN's cache after each deployment may not be sufficient, as client-side caching can still occur. An alternative approach is to generate unique filenames for your assets. This documentation focuses on this method.

Before diving into Cache Busting, it's important to understand Accessing Entrypoints in PHP.

Building the Project

esbuild simplifies the process by allowing you to include a content hash in the output filenames:

$ ./node_modules/.bin/esbuild \ --asset-names="./[name]_[hash]" \ --entry-names="./[name]_[hash]" \ --bundle \ --format=esm \ --loader:.ttf=file \ --metafile=esbuild-meta.json \ --outdir=assets \ --splitting \ resources/css/app.css \ resources/ts/controller_homepage.ts \ resources/ts/controller_search.ts \ ;

For a more deterministic yet unique approach, you can provide your own build identifier, such as one derived from your latest GIT commit hash:


Resolving Filenames in PHP

Since we retrieve filenames from the esbuild metafile, the process remains the same as described in Accessing Entrypoints in PHP.

By including the content hash or a custom build identifier in the filenames, you ensure that each deployment results in a unique filename, effectively bypassing caching issues and guaranteeing that your users receive the latest assets.

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