restore: Auto-clean old blobs from IndexedDB

[goto-bus-stop]

Steps:

• Add expiry timestamp to blobs in IndexedDB
• Implement cleaning up expired blobs from IndexedDB
• Auto-cleanup when a RestoreFiles plugin is installed
• Remove Core dependency from IndexedDBStore and ServiceWorkerStore
  Note that this removed the need for users to fire the sw-ready event, the ServiceWorkerStore now detects whether a serviceWorker is installed on its own.
• Add expiry to ServiceWorkerStore? Don't know if this is necessary since browsers will probably restart the serviceworker at some point and lose all the blobs before we could hope to expire anything.
• Add expiry to file metadata in localStorage
• Add a module that can be used to auto-cleanup Uppy's old blobs without including all of Uppy, so people can run this on every page of their website or whatever at a much smaller byte cost.

[goto-bus-stop]

Added require('uppy/lib/plugins/RestoreFiles/cleanup'), a function that you can call to clean up expired file blobs and metadata without importing Uppy itself.

It's not super tiny unfortunately, about 5kB after gzip:

$ browserify src/plugins/RestoreFiles/cleanup.js -t babelify | uglifyjs -cm | gzip | wc -c | npx pretty-bytes-cli
4.8 kB

[goto-bus-stop]

MDN said something about using clients.get(event.clientId) to only send the message back to the sender, but clientId was undefined for me--i guess that's why we were sending the uppy/ALL_FILES message to all clients too.

[arturi]

Got this in Safari on boot:

On adding file:

Later after refresh:

Could it be that it’s not expecting that IndexedDB database might not exist? 🤔 Just a guess.

[arturi]

In docs, we are using both RestoreFiles and GoldenRetriever now, when referencing the lib/require path. We should standardize. Let’s use GoldenRetriever everywhere? Or do you feel strongly about keeping RestoreFiles name?

[goto-bus-stop]

Could it be that it’s not expecting that IndexedDB database might not exist? 🤔 Just a guess.

Ah good catch! yeah that's most likely it.

e; it was the database migration (adding timestamps to existing blobs) failing if there were no blobs stored. fixed in 68d533e

In docs, we are using both RestoreFiles and GoldenRetriever now, when referencing the lib/require path. We should standardize. Or do you feel strongly about keeping RestoreFiles name?

hmm, the reason i use RestoreFiles in docs is because that's the path you have to require()…so i don't feel strongly about the name itself, but it should be the same as what it's called in the code

[goto-bus-stop]

Rebased, the only new commits are b62ab29 and fdf46b5 (changelog)

[arturi]

Woot woot! Very impressive! Tested, clean up succeeded after recent updates ✔️

A thought about serviceWorker: I think it might stick around forever if you don’t restart the browser, and on mobile its literally forever, because that’s how it’s designed to work. So I think adding expiration dates to serviceWorker is a good idea too.