Why doesn't this library set the "alg" header when generating a key pair?

[treeder]

You can't import a key without knowing the alg, if you try you get a:

Error: "alg" argument is required when "jwk.alg" is not present

Example:

    let key = await jose.generateKeyPair('EdDSA', { extractable: true })
    let privateKey = await jose.exportJWK(key.privateKey)
    console.log("importing right after exporting...")
    let ikey = await jose.importJWK(privateKey) // errors here
    console.log("imported key", ikey)

Is there a reason not to set it?

[panva]

Is there a reason not to set it?

Because it couldn't be made consistent between the different algorithms and runtimes. ECDH keys don't map to a single algorithm in WebCryptoAPI, node:crypto KeyObject has no notion of an algorithm.

[treeder]

Ok, makes sense. But what about for the algorithms that do map properly? Seems like it could set it for those without issues?

[panva]

That would really just be EdDSA because for instance 'rsa' KeyObject instance is applicable to any RS* and PS* algorithm. EdDSA also will be deprecated soon in favour of Ed25519/Ed448 algorithm identifier respectively.