Add JWT authentication page for NGF

[dhurley]

Proposed changes

Checklist

Before sharing this pull request, I completed the following checklist:

• I read the Contributing guidelines
• My branch adheres to the Git conventions
• My content changes adhere to the F5 NGINX Documentation style guide
• If my changes involve potentially sensitive information¹, I have assessed the possible impact
• I have waited to ensure my changes pass tests, and addressed any discovered issues

Footnotes

1. Potentially sensitive information includes personally identify information (PII), authentication credentials, and live URLs. Refer to the style guide for guidance about placeholder content. ↩

[github-actions]

✅ Deploy Preview will be available once build job completes!

Name	Link
😎 Deploy Preview	https://frontdoor-test-docs.nginx.com/previews/docs/1774/

---

[sjberman]

I think we should also mention (either now or once we support remote), that this example uses File and what that means.

[salonichf5]

should we mention explicitly that remote JWT is excluded currently to avoid any confusion

[salonichf5]

Suggested change

	- **realm**: (Optional) The realm parameter sets the authentication realm displayed in the WWW-Authenticate header when authentication fails.
	- **keyCache**: (Optional) Specifies how long NGINX Plus caches the JWKS keys in memory. Valid values include time units like `10s`, `1m`, `1h`. This reduces the need to re-read the secret file for each request. If not specified, keys are cached indefinitely until NGINX is reloaded.
	- **keyCache**: (Optional) Controls how long NGINX Plus caches the JWKS keys in memory. Supported values use standard time units such as 10s, 1m, or 1h. Caching avoids reloading the JWKS from the Secret for every request, improving performance. If not specified, the keys remain cached indefinitely and are only refreshed when NGINX is reloaded.

sounds clearer I think

[salonichf5]

overall looks pretty good to me, just a couple of nits

[JTorreG]

something is weird here.

There is a H2 header about Setup with a sentence followed with another H2 header for Deploy sample applications

Is the "Deploy ..." section part of Setup?

If it is not a subsection, the text under Setup does not make sense by itself.

If it is a subsection all the heading levels after Setup need to be reviewed

[shaun-nx]

Suggested change

	apiVersion: gateway.nginx.org/v1alpha1
	kind: AuthenticationFilter
	metadata:
	name: jwt-auth
	spec:
	type: JWT
	jwt:
	file:
	secretRef:
	name: jwt-auth
	realm: "Restricted jwt-auth"
	keyCache: "1h"
	apiVersion: gateway.nginx.org/v1alpha1
	kind: AuthenticationFilter
	metadata:
	name: jwt-auth
	spec:
	type: JWT
	jwt:
	source: File
	file:
	secretRef:
	name: jwt-auth
	realm: "Restricted jwt-auth"
	keyCache: "1h"

[shaun-nx]

We need to add source: File here otherwise we get this error:

The AuthenticationFilter "jwt-auth" is invalid: 
* spec.jwt.source: Required value