Add GetSigningMethods function

[wisdommatt]

Signed-off-by: Wisdom Matthew talk2wisdommatt@gmail.com

resolves #63

[mfridman]

Is there a good use-case for this?

There is a hard-coded list here: https://github.com/golang-jwt/jwt#signing-methods-and-key-types

[lggomez]

Is there a good use-case for this?

There is a hard-coded list here: https://github.com/golang-jwt/jwt#signing-methods-and-key-types

Well, from a consumers point of view it would be a nice feature to programmatically know the supported features. Case in point from the original issue I ported #63 from:

I'm building a CLI to create tokens, and it would be nice if there was a way to find all registered signing methods.

I'm not happy with the performance of the simple implementation, although making this more performance-friendly will add more unwarranted complexity to the implementation (for instance, the consumer of this package should call this method only once and cache the returned slice of supported methods for further usage)

[mfridman]

I'm not happy with the performance of the simple implementation, although making this more performance-friendly will add more unwarranted complexity to the implementation (for instance, the consumer of this package should call this method only once and cache the returned slice of supported methods for further usage)

If performance is an issue, as you said, it's likely the caller's responsibility to handle that. This looks sane to me.

[AlexanderYastrebov]

To address the I'm building a CLI to create tokens, and it would be nice if there was a way to find all registered signing methods. usecase as well as I'm not happy with the performance of the simple implementation I think the alternative could be to provide a list of registered alg names instead.

This way the list could be used for the CLI help but also could be iterated to obtain respective SigningMethod if needed.

If that sounds reasonable, I would like to propose the PR #123

[oxisto]

Superseded by #123