Feature: allow to use an existing configmap to replace nginx conf

[AlexGacon]

Feature Description

To facilitate integration of a geonode instance with an external application, it would be great to have the possibility to add CORS origin info into NGINX configuration.

Proposed Solution

• Add in values.yaml a new variable block nginx.external_domain.
• In charts/geonode/templates/nginx/nginx-conf.yaml, if extern_domain is enabled, add Access-Control-Allow-Origin directive in the configuration, targeting the configured domain.

Additional Information

Any additional information or context that may be helpful in implementing the feature.

[AlexGacon]

I considered that the underlying file name is not changed but perhaps it is better to allow its configuration too.

[AlexGacon]

I can take care of it if it is ok with you.

[mwallschlaeger]

yes I can understand the requirement here. I guess for most cases it would be enough to overwrite the configuration just partially. Like only the geoserver, or add addition configuration to a specific part. But sure for some use-cases also using a a whole self written config will be required.

If you create a PR i can definitely take a look at it.

[AlexGacon]

Ok. You will receive my PR when done.

[AlexGacon]

I updated the issue following the discussion in the proposed PR.