Add serverSnippets to TransportServer

[LorcanMcVeigh]

Proposed changes

This PR adds Snippet feature to the TransportServer resource.

Checklist

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• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
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[pleshakov]

Hi @LorcanMcVeigh

Shall we also add streamSnippets field that configures snippets in the stream context ? similar to http-snippets https://deploy-preview-1413--nginx-kubernetes-ingress.netlify.app/nginx-ingress-controller/configuration/virtualserver-and-virtualserverroute-resources/#using-snippets

[ogarrett]

Hi @LorcanMcVeigh

Shall we also add streamSnippets field that configures snippets in the stream context ? similar to http-snippets https://deploy-preview-1413--nginx-kubernetes-ingress.netlify.app/nginx-ingress-controller/configuration/virtualserver-and-virtualserverroute-resources/#using-snippets

I agree - there are some directives that can only be specified at the stream context (including geo, keyval and map) and there may be cases where it's convenient to apply a directive there so that all stream servers inherit it

[pleshakov]

Hi @LorcanMcVeigh

the changes look good to me.

However, because of the future streamSnippets, we need to rename snippets to `serverSnippets, which would be similar to http and server snippets for VS :

apiVersion: k8s.nginx.org/v1alpha1
kind: TransportServer
metadata:
  name: dns-tcp
spec:
  streamSnippets: |
    limit_conn_zone $binary_remote_addr zone=addr:10m;
  listener:
    name: dns-tcp 
    protocol: TCP
  serverSnippets: |
    limit_conn addr 1;
    limit_conn_log_level error;
  upstreams:
  - name: dns-app
    service: coredns
    port: 5353
  action:
    pass: dns-app

[pleshakov]

@soneillf5
the last change looks good! however, because of the change, there is some remaining code and logic, which is not really used - that's why a few comments below

[pleshakov]

🚀