Add key generation subcommands

[sbihel]

Also move to clap v3 (structopt has been integrated in clap).

---

Here's my proposal for the subcommands.

key
├─ generate
   ├─ secp256k1
   ├─ ...
├─ did
   ├─ web
   ├─ pkh:tz
   ├─ ...

[clehner]

key generate command looks good to me.

Suggesting to rename the third key type to Secp256r1: #259 (comment) #259 (comment)

What would the did part be?

├─ did
   ├─ web
   ├─ pkh:tz
   ├─ ...

[sbihel]

Suggesting to rename the third key type to Secp256r1

Actually, do you think it would be better to name them k256 and p256?

What would the did part be?

It's to replace the key-to-did command, but it's obviously not the greatest name 😅

[clehner]

Actually, do you think it would be better to name them k256 and p256?

"Secp256k1" would be consistent with the usage here:

• https://w3c-ccg.github.io/lds-ecdsa-secp256k1-2019/#dfn-ecdsasecp256k1signature2019
• https://w3c-ccg.github.io/did-method-key/#secp256k1
• https://identity.foundation/sidetree/spec/v1.0.0/#key-algorithm

Usage of the term Secp256r1 seems to be a little less consistent, e.g.:

• https://w3c-ccg.github.io/did-method-key/#p-256
• [PROPOSED WORK ITEM] ECDSA Secpr1 Cryptosuite v2019 w3c-ccg/community#228

But there is mention of Secp256r1 in the VC Data model V1 context:

• https://github.com/w3c/vc-data-model/blob/c48544caa8e151d289472daa5ebaacc78aaf2a46/contexts/credentials/v1#L124-L125

The JOSE table of elliptic curves includes secp256k1 and P-256:
https://www.iana.org/assignments/jose/jose.xhtml#web-key-elliptic-curve

We could also have additional (hidden) aliases like for p256, P-256, k256, etc.

It's to replace the key-to-did command, but it's obviously not the greatest name

OK. Not bad I think. If it was key to-did, that could keep the verb/imperative style. Or it could be moved into a did subcommand (e.g. did from-key, did generate, did create) In #255 I'm adding more DID operations also.

[sbihel]

I didn't find a way to override the -h help flag on a per command basis. Is the did-auth command part of the latest publish version of DIDKit CLI?

[clehner]

I didn't find a way to override the -h help flag on a per command basis.

I see, did-auth's -h previously overrided the default short help command, but on the newer clap version used here, this results in an error (Short option names must be unique for each argument, but '-h' is in use by both 'holder' and 'help'). I don't see a way to override it now either. Probably it's good to just let -h be for help. Although in the newer clap it looks like -h is the same as --help while previously -h showed a shorter help...

Is the did-auth command part of the latest publish version of DIDKit CLI?

Yes (didkit-cli crate v0.1.1, and on ghcr.io).