Improve prefetcher

[johanjanssens]

• Use a webworker for fetch() instead of handling the request on idle to avoid blocking main thread
• Implement support for transclusion and substitution of html
• Default config, fetch all links inside elements with class prefetch
• Add support for pagination and links relations, Improve pagination #452

Resources:

• https://github.com/joomlatools/joomlatools-framework/blob/1.0/code/media/lib_koowa/js/koowa.js
• https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver
• https://developers.google.com/web/updates/2017/09/abortable-fetch

Web workers

• https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Using_web_workers
• https://dev.to/trezy/loading-images-with-web-workers-49ap
• https://github.com/developit/greenlet
• https://github.com/developit/workerize
• https://github.com/GoogleChromeLabs/comlink
• https://github.com/GoogleChromeLabs/clooney
• https://medium.com/google-developer-experts/running-fetch-in-a-web-worker-700dc33ac854
• https://vanillajstoolkit.com/boilerplates/umd/
• https://github.com/jcubic/wayne

[johanjanssens]

Investigate caching prefetched pages in browser cache and serving them using a service worker. This approach would also allow to rewrite the html stream, instead of using javascript to manipulate the dom. References:

• https://jakearchibald.com/2016/streams-ftw/
• https://developers.google.com/web/updates/2016/06/sw-readablestreams

[johanjanssens]

• The transclusion and substitution could be into a standalone stitcher script
• The service worker could go into a standalone streamer script

[johanjanssens]

See also:

• https://postlight.github.io/trimmings/
• https://unpoly.com/up.link
• https://unpoly.com/up.fragment
• https://hotwire.dev/

[johanjanssens]

Idea: would it be possible to proxy through the webworker to a cloudflare worker domain to handle cloudflare caching without the proxied domain being behind cloudflare? Might require a reverse proxy server and a custom cloudflare domain? Eg https://cdn.joomlatools.com, and an Apache proxy?