ae3dadfc66
* cache asset images more aggressively * more careful about which gets the manual surrogate key * fix rendered-content-link-checker script too * feedbacked
27 lines
1.0 KiB
JavaScript
27 lines
1.0 KiB
JavaScript
// This middleware rewrites the URL of requests that contain the
|
|
// portion of `/cb-\d+/`.
|
|
// "cb" stands for "cache bust".
|
|
// There's a Markdown plugin that rewrites all <img src> values
|
|
// from `<img src="/assets/foo/bar.png">` to
|
|
// `<img src="/assets/cb-123467/foo/bar.png">` for example.
|
|
// We're doing this so that we can set a much more aggressive
|
|
// Cache-Control for assets and a CDN surrogate-key that doesn't
|
|
// soft-purge on every deployment.
|
|
|
|
const regex = /\/cb-\d+\//
|
|
|
|
export default function assetPreprocessing(req, res, next) {
|
|
if (req.path.startsWith('/assets/')) {
|
|
// We're only confident enough to set the *manual* surrogate key if the
|
|
// asset contains the cache-busting piece.
|
|
if (regex.test(req.url)) {
|
|
// We remove it so that when `express.static()` runs, it can
|
|
// find the file on disk by its original name.
|
|
req.url = req.url.replace(regex, '/')
|
|
// The Cache-Control is managed by the configuration
|
|
// for express.static() later in the middleware.
|
|
}
|
|
}
|
|
return next()
|
|
}
|