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4 items tagged “serviceworkers”

2024

tiny-world-map (via) I love this project. It’s a JavaScript file (694K uncompressed, 283KB compressed) which can be used with the Leaflet mapping library and provides a SVG base map of the world with country borders and labels for every world city with a population more than 48,000—10,000 cities total.

This means you can bundle an offline map of the world as part of any application that doesn’t need a higher level of detail. A lot of smaller island nations are missing entirely though, so this may not be right for every project.

It even includes a service worker to help implement offline mapping support, plus several variants of the map with less cities that are even smaller.

# 21st April 2024, 10:11 pm / gis, javascript, mapping, svg, serviceworkers

2021

servefolder.dev (via) Absurdly clever application of service workers and the file system API: you can select a folder from your computer and the contents of that folder will be served (just to you) from a path on this website—all without uploading any content. The code is on GitHub and offers a useful, succinct introduction to how to use those APIs.

# 12th December 2021, 6:32 pm / browsers, javascript, serviceworkers

Introducing Partytown 🎉: Run Third-Party Scripts From a Web Worker (via) This is just spectacularly clever. Partytown is a 6KB JavaScript library that helps you move gnarly poorly performing third-party scripts out of your main page and into a web worker, so they won’t destroy your page performance. The really clever bit is in how it provides sandboxed access to the page DOM: it uses a devious trick where a proxy object provides getters and setters which then make blocking API calls to a separate service worker, using the mostly-forgotten xhr.open(..., false) parameter that turns off the async default for an XMLHttpRequest call.

# 23rd September 2021, 6:29 pm / async, javascript, webworkers, serviceworkers

2018

Everyone can now run JavaScript on Cloudflare with Workers. This is such a brilliant piece of software design: Cloudflare took the service workers spec and used it as the basis for their edge-executed JacaScript feature. This means you can run server-side JavaScript in hundreds of edge locations worldwide, applying custom dynamic logic (including additional async cached fetch() calls) with only around 1ms if additional overhead. The pricing model is a steal: $0.50 per million requests with a $5/month minimum.

# 13th March 2018, 4:36 pm / cdn, javascript, cloudflare, serviceworkers