window.showDirectoryPicker opens up a whole new world

https://steveharrison.dev/showdirectorypicker-opens-up-a-whole-new-world/

by steveharrison • 1 month ago

113 108 1 month ago

I'm really excited about window.showDirectoryPicker and the local-first web apps it will enable. There's lots of talk about local-first sync engines, but the best sync engine is one you don't even manage, like the user's file system / cloud storage service!

Ajedi326• 1 month ago

Yes, I think this modern trend towards storing user data in app/website-specific databases instead of in files has been bad for consumer freedom. Files are naturally portable and provide a interface for inter-operating with competing software in a way that data stored in the cloud or an app-specific database does not.

APIs that encourage websites to store user data in files are a positive thing.

acbart• 1 month ago

Some of the permissions problems related to window.showDirectoryPicker have been frustrating. I'm developing a client-side Python web framework, and during development I need to mount the library locally; I hand off the directory to Pyodide using this API. But that doesn't work in VSCode's internal browser, apparently because the API just simply isn't able to be approved.

Yiin• 1 month ago

sounds like vscode issue more than anything else

tantalor2• 1 month ago

Usability issues? In vscode? No...

yread• 1 month ago

But webkitdirectory="true" could already do that, no?

justusthane• 1 month ago

No, they're very different. Using webkitdirectory="true" on an <input> element just allows you to select a directory to e.g. upload it to the server. It's a one-time operation.

This API returns a handle to the selected directory, giving the webpage ongoing read/write access to the directory.

You couldn't use the former to e.g. create a local-first notes app that stores its files on disk.

simonw• 1 month ago

That's read-only.

It's very cool though, and worth learning about for anyone who's unfamiliar.

I have a demo page showing what it can do here: https://tools.simonwillison.net/webkitdirectory

explodes2• 1 month ago

First time I've heard about this. I'll have to look into the security model around it. I'm curious what safeguards are in place to prevent click jacking. I know showing a file picker """should""" be enough of a warning to users to be careful, but it's not hard to imagine a world where a couple of fish accidentally bite the bait of an allow-button, or because they followed instructions they incorrectly trusted.

explodes2• 1 month ago

Looks like these safeguards are in place:

* System and root directories cannot be selected. * Can only being activated after user action. * Requires https. * Double-confirmation for write access.

No API like this could ever be bulletproof, but it's a start I guess.

Very cool API though, and it really does open up a whole new world of possibilities.

ptx2• 1 month ago

Those are some pretty flimsy safeguards. I don't keep my secrets in system directories and using HTTPS doesn't mean the site isn't malicious.

mschuster91• 1 month ago

System and root directories cannot be selected.

That desperately needs something like the Public Suffix List [1] - a community-managed list where authors of software can blacklist directories containing sensitive files or such files directly for all browsers implementing this feature.

If I were to design such a list, it would include ~/.ssh, ~/.aws, ~/.config, ~/Library, ~/.{ba,z}sh{rc,_profile,_history}, ~/.m2, ~/.npm, ~/.npmrc, ~/.profile at the very least. Because users will get phished.

[1] https://en.wikipedia.org/wiki/Public_Suffix_List

cicko2• 1 month ago

This is something you should explain to the Firefox critics.

asdfsa325• 1 month ago

Chrome and friends (Edge, Opera) are basically the new IE6 and only people who are new or forgetful will disagree. I hate Mozilla for missing up so bad with their stewardship of Firefox time and again, but alas, it is the only reasonable option on the table.

And while I do hate Mozilla, Google is to be disliked even more.

bigrocketapps3• 1 month ago

Currently using this in socket2.me

Not truly supported across all mobile browser currently, but it's certainly better than just one year ago.

tantalor2• 1 month ago

https://caniuse.com/mdn-api_window_showdirectorypicker

* Global 75.2%

Mainly missing Safari and Firefox

asdfsa325• 1 month ago

This new IE6 called Chrome, I hate it.

chrismorgan• 1 month ago

You say “mainly missing Safari and Firefox”, but the better way to look at it is “only Chromium”. There is only one implementation, and the other two major implementers have explicitly rejected it. And we don’t standardise things without at least two implementations.

jaen• 1 month ago

Unfortunately currently only supported by Chrome/Chromium:

https://developer.mozilla.org/en-US/docs/Web/API/Window/show...

AlienRobot4• 1 month ago

Chromium has around the same market share as Windows, so at this point I feel people are targeting it as a web application development platform just as people target Windows.

inigyou2• 1 month ago

(intentionally, because it's a massive security risk and only Google doesn't care about endpoint security)

znpy2• 1 month ago

Chrome introduced a new API, window.showDirectoryPicker() that allows the user to grant access to a directory on their computer and allow a website to read/write everything inside.

I mean, what could go wrong?

It's not like an user is tricked into uploading a file from a folder (let's say, the main "Documents" folder) and some malicious website steals all the files over there.

bigrocketapps3• 1 month ago

If you tried this out in Linux, for example, the system would block you from selecting folders that contain files that are flagged as dangerous or "system files". I'm assuming this was implemented across all OSes.

blharr• 1 month ago

That does not sound at all reassuring, that the only safeguard is the system blocking access and that the API has no safeguard.

Its also easily possible to have sensitive files misplaced, especially for a general non-technical user that would be the one falling for a browser hijacking attack

znpy2• 1 month ago

i give zero F about whatever is in my /usr, /var/lib and /opt folders.

what are websites gonna steal, debian binaries and libraries?

all my important stuff are in my home directory, which is owned (read+write) by me, the same user running the browser.

AlienRobot4• 1 month ago

I wish we had this in the operating system. It would solve an immense number of risks such as data deletion from bugs and even ransomware.

asdfsa325• 1 month ago

MacOS has this and what happens is that you get into the habit of just clicking through it. It won't help with ransomware, only backups would.

AlienRobot4• 1 month ago

That just means it's poorly designed. There has to be a way to design this in such way it works.

jeroenhd• 1 month ago

Which operating system do you mean? Flatpak has this already, Android enforces this kind of API for shared files, Windows UWP has pretty much the exact same API (https://learn.microsoft.com/en-us/uwp/api/windows.storage.pi...).

App developers will often choose not to sandbox their applications because it's a lot easier (and sometimes faster) do to all file management yourself, but the APIs are there and ready to be used.

AlienRobot4• 1 month ago

Flatpak is probably the worst way to "have" this possible. It's completely opaque to both app and user. If you ever tried to run an .exe through flatpak'd bottles, you'll run into an issue where .dll's aren't found because you didn't install flatseal first to configure permissions. That's not operating-system level integration. That is actually very poor design that a user requires a separate app (flatseal) to configure how the sandbox works.

I was thinking about desktop OS's, actually.

You don't need to use that Windows API. You can just access any file you want. There is no reason a music player, for example, needs to access ~/Pictures. An arbitrary program requiring access to all your files is a huge red flag, but it's a red flag that users aren't allowed to see. Proper filesystem permissions would fix that.

cicko2• 1 month ago

Too many prompts and not an official API. Back in the day, IE also had tons of "great" and novel ideas, including COM+ something something.

libria• 1 month ago

They also popularized XMLHttpRequest. Sometimes a flexible idea can trend to the greater ecosystem.

steve19772• 1 month ago

ActiveX something something!

buckle8017• 1 month ago

A whole new world of phishing.

streptomycin5• 1 month ago

This isn't new, the API has been around for several years. Unfortunately Mozilla and Apple say they are never going to implement it because of security concerns https://github.com/mozilla/standards-positions/issues/154

It is a great API though, I wish the other browser vendors liked it! Because currently us PWA developers are really limited when trying to make apps that work with local data, at least in non-Chrome browsers.

sharperguy• 1 month ago

You could implement it this way:

- the first time you select a directory it must be empty

- you can drag files in there afterwards

- the directory gets whitelisted for future use

Probably has bad usability, but would be more secure.

NooneAtAll3• 1 month ago

fortunately*

benregenspan• 1 month ago

I'd love for Google to figure out something comparable for the Drive API (currently it's not possible to grant read/write access to a single folder; you need to grant access to the entire drive!): https://issuetracker.google.com/issues/36760598?pli=1

I think the fact that the above issue has been open for a very long time is one indication of how difficult and sensitive this type of access control API is. The Google Drive API could be a proving ground for getting the UX right for this (including tricky details like how to manage persistent access to a folder with clear disclosure and user controls).

ethbr1• 1 month ago

Is it really that complicated?

Why not just create per-domain browser-controlled folders (cert-linked?) that are abstracted into a simple read/write API via the browser (with subfolders allowed under that domain's root), disallow cross-domain access... and then build browser-mediated linking for use cases where you want to flow files from (non-domain) to (domain) to (non-domain)?

So essentially local storage with better integration with the actual filesystem, that's browser-controlled.

Allowing websites to have arbitrary (even user-approved) access directly to the real filesystem seems like a bad idea, when most use cases could be handled by a browser-mediated filesystem-like abstract view.

codedokode6• 1 month ago

Firefox position is completely valid. I think a safe option would be to allow access only to a specific directory like "~/Internet files" or something like this. This way the user could grant the access but not to sensitive files. And add an option in about:config to lift the restriction for power users.

Also, there is a risk of a site writing malware executable, and Linux currently has no sandboxing for such executables so the system would be completely owned once the user runs the program. So the directory should not allow storing executables.

shortercode2• 1 month ago

Both sides are valid. Is it a security risk? In the right conditions yes. But on the other side of it there’s user consent, limited per domain access, and the capability to do multi file editor style apps.

I think the WebKit take on this is good and a better fit for most apps. They instead implemented Origin Private File System. Which is based on the same API bits but the folder is only accessible by the website. The downside is the user loses some control over the files:

- can’t see what’s being stored

- can’t easily backup those files

- has to use that web app to access the files

- usual nonsense about important files being classed as “cookies” or some nonsense by cache cleaning tools, leading to users deleting their data without realising it

Theodores• 1 month ago

Ah, but it is new to Claude. Claude has main character vibes, so it is always about Claude. Isn't he clever?

Claude can stay in his own lane, I want to know how I can use this during development to simulate uploading photos, so Chrome only is okay for my purposes. But I want to know how to do it, not how much better Claude is than me, forever able to do anything I can do but better.

KetoManx64• 29 days ago

But I want to know how to do it, not how much better Claude is than me, forever able to do anything I can do but better.

So tell the clanker to explain to you in detail about how the system works? It's a piece of code that does what you tell it to, treat it as so.

rvz• 1 month ago

Phishers and exploit developers are celebrating and jumping for joy over yet another way to deploy their payload to their victims.

What are the many ways could this possibly go wrong?

Anduia• 1 month ago

"Choose your browser cache folder to improve performance"

codedokode6• 1 month ago

Choose .autostart directory to install a video codec needed to play this video.

ptx2• 1 month ago

So websites can now nag users to allow access to the root of their local disk and then read all their files and settings, all their SSH keys and other passwords?

From what I gather from the docs [1], this API gives you a FileSystemDirectoryHandle object, and then you just call getDirectoryHandle() on that to recursively read the the entire filesystem. The spec [2] has some vague suggestions about blacklisting certain particularly sensitive files, which doesn't seem reassuring.

[1] https://developer.chrome.com/docs/capabilities/web-apis/file...

[2] https://wicg.github.io/file-system-access/#privacy-wide-acce...

Ajedi326• 1 month ago

Root directory would be on that blacklist for sure.

Those "vague suggestions" actually seem to include some pretty specific examples.

A user’s entire "home" directory. Individual files and directories inside the home directory should still be allowed, but user agents should not generally let users give blanket access to the entire directory.

EnergyAmy• 1 month ago

That's not at all specific. What individual files and directories?

jaffathecake• 1 month ago

So websites can now nag users to allow access to the root of their local disk

No, Chrome doesn't allow this.

Here's a simple demo: https://output.jsbin.com/kekekac/quiet - note that you can't select root, Downloads etc.

move-on-by• 1 month ago

Ah yes, totally secure. I’m sure there will be no unforeseen problems or bypasses.

croes5• 1 month ago

In this example

https://web.dev/patterns/files/open-a-directory

I can select Downloads

cnr• 1 month ago

Let's not forget that, at the same time, Google forces every developer of any Android app to register in the Google database using an ID scan, otherwise no one can install it.

All for the sake of "dear user safety".

superjan• 1 month ago

Is the camera roll excluded? I bet I am not the only one who has a passport picture in there. I don’t know about other people’s camera rolls, but I bet it is occasionally more saucy than mine.

(Sorry for not testing. Chrome-hater)

sarreph• 1 month ago

I think something that is a mix between localStorage or IndexedDB and access to the user's filesystem would be better.

I agree with the comments about how much of a security risk this poses. But, isn't that the case with any binary or executable files and apps we download from the internet anyway?

It would be cool if you could have a specially-demarcated directory (e.g. even inside the application like `~/Applications/Chrome/<website>/local_files`) which you can just open super easily with a button from Chrome, and just copy files over into that directory as needed. Would provide the benefits of a more secure enclave with the flexibility of being on the filesystem.

streptomycin5• 1 month ago

That is similar to https://developer.mozilla.org/en-US/docs/Web/API/File_System... except AFAIK that does not allow any way to access it as a normal directory outside the browser.

steve19772• 1 month ago

I'm not sure if this is meant to be ironic?

"You can also create folders within the app and move photos into them, and it all happens on your filesystem."

Why, yes. But you can also do that with Finder.

And if you want to work with local data, why use the often inferior web-based widgets and toolkits instead of native ones?

This seems to be the worst of both worlds so to speak.

coldpie• 1 month ago

I used to think like this too, but somewhat surprisingly to myself, I have actually come around to deciding the web API is the most user-forward API that closed-source software can target, and it is actually good for end users for closed-source software to target it. This is because web API software is distributed as plaintext to be interpreted by software under user's control, the browser. This gives a ton of power to the user. We as end users can develop browser extensions, CSS hacks, and so on, to make this closed-source software work better for us.

I frequently do this; why can't I paste into this password text box? Screw it, I go into dev tools and enable pasting into it. Who decided grey-on-grey text was a good idea? Screw it, I got into dev tools and make the text black. Why can't I copy the text on this page? Screw it, I go into dev tools and yank it straight from the DOM. Why does this stupid animation take so long? Screw it, I go develop a greasemonkey script to set the animation timer value to 0. This is all quite easy with web API software, but would be be extremely difficult with a compiled binary.

This is to say nothing about the cross-platform benefits. No one's shipping a HaikuOS binary, but most web apps work just fine there, depending on browser feature support.

I think it is also a good choice for open-source software for the same reason. It provides a common, well-tooled API for users to hack the software they are using. But open-source software has other hackable options that make it less of a strong argument there.

Native toolkits definitely have a lot of nice features that the web API doesn't (yet) have, and there's a ton of value in the consistency native toolkits provide. But I think I've come around to valuing hackability over those features, so I'm actually now a web API fan. Again, surprising myself with this switch :)

Ajedi326• 29 days ago

There are a lot of things to like about the web as an application platform. The security model is a big one for me. There aren't many other application platforms out there where you can just download random apps off the internet and run them with zero worries they'll screw up your system. Plus the web is an open standard, works on desktop and mobile, and has multiple competing independent open source implementations.

petcat• 1 month ago

The best app is the one that is available on your platform.

Unfortunately I think the ubiquity of browser-based web apps are the only reason the Linux desktop is even remotely usable at this point.

qwertytyyuu• 1 month ago

Read, sure, already can do that with file upload. Write sounds like a disaster waiting to happen

nasso_dev• 1 month ago

it's a bit of a shame that TFA does not mention that this is a non-standard API pushed by google only (all three editors of the draft are google engineers)

both Mozilla[1] and Apple[2] are opposed to it

encouraging people to build apps that only work in google web browsers actively harms the web and sends a signal to google that they can in fact keep doing this

[1] https://mozilla.github.io/standards-positions/#native-file-s...

[2] https://webkit.org/standards-positions/#position-28

rightlane• 1 month ago

We are introducing new and exciting ways to expose environment variables and PII every day! Introducing features like this while we are in the midst of uncontrolled supply chain attacks feels like a not great idea.

functionmouse• 1 month ago

everything is Chrome in the future

llosio• 1 month ago

photopea.com already does this...

It's a full photoshop-like image (svg, gif, and video too) editor that runs completely on the browser, and has the ability to load a folder as you "Local Projects" folder.

I'm surprised nobody commented this already

steveharrison4• 29 days ago

Nice one!

danhardman2• 1 month ago

A few people have suggested adding a blacklist for dangerous directories or validating directories are empty first.

Why not just make the API create a new directory rather than selecting one? There's still a risk people create a directory in a shared location - but at least they're only risking the new directory then, right?

Ajedi326• 1 month ago

I think the intended use case is for things like "give my music player access to my music library" or "open a project directory in this IDE", which wouldn't work well if every app were confined to its own directory.

danhardman2• 1 month ago

I guess, but it seems pretty typical to expect to install a new software or start a new project and require some form of loading/importing content in. It wouldn't exactly destroy the experience or at least the trade-off seems worth it imo

no_way• 1 month ago

I am using this api for music player[0] in the browser. Biggest share of my users are using Chromebooks, where besides Android apps are not much alternatives. If this API was not available closest thing would be to make an Electron app, which has much more broad system access to users device than a website using showDirectoryPicker.

Regarding security I think Chrome got right balance on this: you always need to select folder, sensitive ones are excluded, on repeat visits if you try to access a file, it asks you permission again, you can't get full filename paths and so on.

[0] https://github.com/minht11/local-music-pwa

insin• 30 days ago

I'm using this API in the internal [1] model-independent LLM chat app I work on at an F100, and it ruined using the Claude and ChatGPT web interfaces for me outside of work [2] because I'm used to being able to point the model at a folder so it can be directed to find and pull in relevant context itself, being able to add folder mid-chat and saying "you do it", and being able to have the model run code to work with local files of any size your browser can handle (every time we released a new version people would drag in their huge Excel files and go "still doesn't work" as we used to extract and context stuff the contents, but now it can poke around in them directly to find sheets/headers/structure and write code to do whatever they wanted).

Claude Opus on its own with filesystem tools built around the FileSystemDirectoryHandle API [3] makes for a pretty decent coding agent - I've been using the app to write itself live on its own development server ever since it got the ability to edit its own files, which is some of the most fun development I've done recently. I think writing your own harness is probably the most fun thing you can do with an LLM, which is why so many people do it - getting the model to add and then start using a new tool you had an idea for in the same chat is always fun.

[1] which seems like the best scenario for it in terms of the security/privacy issues it poses

[2] I ended up creating an MCP server rooted to a specific local directory - which I can expose to them via Cloudflare Tunnel - and a browser extension which adds a folder picker button to their chat interfaces, so I can get an almost-equivalent experience. This is really ugly in ChatGPT but works as well as I'm used to in Claude.

[3] as a bonus, the tools you write against this API will also be compatible with the Origin private file system (OPFS) API if you want to give your chats a virtual filesystem for the model to write to, or to copy user-attached files into

steveharrison4• 29 days ago

Cool use-case!

window.showDirectoryPicker opens up a whole new world

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