Uses browser automation via Puppeteer.
Will be rewritten to use Proton's Drive SDK once it's stable and has docs.

Installation

# recommended method
# alias pdown to one of these
npx pdown
bunx pdown
pnpx pdown
yarn dlx pdown

# alternative		   # won't update automatically
npm add -g pdown   	   # npm update -g pdown
bun add -g pdown   	   # bun update -g pdown
pnpm add -g pdown	   # pnpm update -g pdown
yarn global add pdown  # yarn global upgrade pdown
# omit the global arguments when using via script

Usage

via command-line

$ pdown --help
Usage: pdown [options] [command]

Commands:
  dl|download [options] <URL/ID...>  download Proton Drive shares
  ls|list [options] <URL/ID...>      list files in Proton Drive shares
  help [options] [command]           display help for command

Global Options:
  -c, --cookies <FILE>               path to a Netscape cookie file
  -d, --debug                        show more informations and write log to ./pdown.log (env: DEBUG)
  --json                             output results and logs as JSON
  -p, --password <PASSWORD>          share password, if set (env: SHARE_PASSWORD)
  --puppeteerOptions <OPTIONS>       options to pass to Puppeteer (JSON) - https://pptr.dev/api/puppeteer.launchoptions
  -q, --quiet                        suppress all output except errors
  --speed <KBPS>                     limit connection speed (in kilobytes per second)
  -u, --user-agent <UA>              override default user agent (env: USER_AGENT)
  --verbose                          same as --debug (env: DEBUG)
  -V, --version                      output the version number
  --help                             display help for command

dl Options:
  -o, --output <PATH>                set download folder path (default: current directory)
  -h, --human-readable               print sizes like 1K 234M 2G instead of bytes
  --si                               like --human-readable, but use powers of 1000 not 1024

ls Options:
  -r, --recursive                    list files recursively in folders (default: false)
  -h, --human-readable               print sizes like 1K 234M 2G instead of bytes
  --si                               like --human-readable, but use powers of 1000 not 1024

$ pdown ls KGER0RS624#LzmiMIuikOuj --recursive
KGER0RS624#LzmiMIuikOuj - pdown
Path                              Size      MIME Type
example.txt                       54B       text/plain
subfolder/example.jpeg            1048576B  image/jpeg
subfolder/subfolder-2/example.mp4 13631488B video/mp4

$ pdown ls KGER0RS624#LzmiMIuikOuj --json | jq '.message | fromjson'
[
  {
    "url": "https://drive.proton.me/urls/KGER0RS624#LzmiMIuikOuj",
    "files": {
      "mimeType": "folder",
      "name": "pdown",
      "children": [
        {
          "mimeType": "folder",
          "name": "subfolder"
        },
        {
          "mimeType": "text/plain",
          "name": "example.txt",
          "size": 54
        }
      ]
    }
  }
]

# download to custom location
$ pdown YXNRS51SXM#lvWyeftvX7R7 -o ~/Downloads
$ cat ~/Downloads/example.txt
:)

# download password protected share
$ pdown Y5J2AT9QJ0#HjVxIlCjfd99 --password 'love' --quiet

# download multiple shares concurrently using SI measurements - https://www.bipm.org/en/measurement-units/si-prefixes
$ pdown KGER0RS624#LzmiMIuikOuj 65PCM21WW8#CxaogwECfsqg --si --speed 1500
pdown.zip            |████████████████████████▒░░░░░░|  81% | 12.39M /  15.29M | 1.50M/s
cool video.mp4       |█▒░░░░░░░░░░░░░░░░░░░░░░░░░░░░░|   3% | 13.64M / 362.08M | 1.50M/s

# run with visible GUI
$ pdown YXNRS51SXM#lvWyeftvX7R7 --puppeteerOptions '{"headless": false}' --quiet

# run with custom chromium binary, required on ARM64 (https://github.com/puppeteer/puppeteer/issues/7740)
$ pdown YXNRS51SXM#lvWyeftvX7R7 --puppeteerOptions '{"executablePath": "/usr/bin/chromium-browser"}' --quiet

via script

import PDown from 'pdown';

const pdown = new PDown({
	downloadPath: process.cwd()
});

pdown.on('downloadcomplete', ({ shareID }) => {
	console.log(`[${shareID}] Download complete`);
});

await pdown.dl(new Set(['https://drive.proton.me/urls/65PCM21WW8#CxaogwECfsqg']));

FAQ

I get a 'Permission Denied' error.

Files have to be shared publically and item password needs to be provided if set.

I set the permission to 'Anyone with the link', but I still can't download.

Please open an issue!

Acknowledgements

Inspired by gdown.
Special thanks to cli-guidelines.