Add proxy to Tekton Results API server

[xinnjie]

Changes

Add proxy to Tekton Results API server. Make a move on tektoncd/results#82
/kind feature

Test case

get('http://localhost:8000/apis/results.tekton.dev/v1alpha2/parents/default/results') return a results list.

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Release Notes

Add proxy to Tekton Results API server

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[tekton-robot]

Hi @xinnjie. Thanks for your PR.

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[AlanGreene]

Hi @xinnjie, thanks for the PR. However, I think we need a plan / design for how this is going to be used before we start making code changes, otherwise it's not clear if this is the best approach.

Also FYI, the APIs exposed by the Dashboard already support proxying requests to other services in the cluster if needed using the Kube API server proxy.

i.e. using /api/v1/namespaces/tekton-pipelines/services/tekton-results-api-service:http/proxy/

For example, to access the /v1/properties API provided by the Dashboard itself using this mechanism I would make a request to GET /api/v1/namespaces/tekton-pipelines/services/tekton-dashboard:http/proxy/v1/properties

We would just need to configure the correct RBAC to allow these requests, creating a role granting the appropriate verbs for services/proxy, restricting it just to Tekton Results in this case (I assume it would only need access to tekton-results-api-service).

[AlanGreene]

Closing for now, we can reopen if needed after there's a plan in place.

[xinnjie]

@AlanGreene
Thanks for your explanation. The proxy mechanism is great! I should know it earlier.

I'd like to propose a TEP about Results Virtualization in Dashboard. General idea is at tektoncd/results#82 (comment). Shall we have some discussion?