Decrypting a stream in the browser eats the memory

[janosNH]

I'm trying to download a symmetrically encrypted large file from a webserver and decrypt it. In Node using streams for encryption and decryption works fine w/ any size of files. I use nearly identical code in the browser. It works w/ ~30MB files, but fails w/ ~700MB. I get this exception: 'Error decrypting message: Array buffer allocation failed'
The relevant part of my code:

async function download () {  
    const fileStream = streamSaver.createWriteStream('your.img')  
    const res = await fetch(url)  
    const bodyStream = res.body
    const message = await openpgp.readMessage({binaryMessage: bodyStream})
    const decrypted = await openpgp.decrypt({
        message,
        passwords: pw,
        format: 'binary'
    })
    return decrypted.data.pipeTo(fileStream)
}

I suspect readMessage tries to read everything from the stream. How can I avoid it?
Thanks for your help.

[twiss]

Hey 👋 Do you have openpgp.config.allowUnauthenticatedStream set? (To be fair, I'm not sure why this would only affect web streams, but just to check.) Failing that, the underlying issue you're running into may be the same as #1012. I'm not aware of a workaround, but that thread does contain some hints about where to start looking, if you want to dig into this.

[janosNH]

You saved my day! openpgp.config.allowUnauthenticatedStream = true works. In node I used file streams not fetch, maybe that's the difference.

Thanks for your quick help.

[twiss]

👍 In that case, I suspect that Node.js was also allocating more memory than needed, but perhaps less noticeably so. But, I'm glad that that fixed it :)