Week notes: passed Red Hat certified specialist in OpenShift Administration exam, attended community session on client-go informers code walk-through #25

kubernetes

June 20, 2021

Very quick notes from this previous week:

passed Red Hat certified specialist in OpenShift Administration exam

This is what all I did for this last whole week (mostly).

• Prepared for the Red Hat Certified Specialist in OpenShift Administration (EX280V45K) exam.
• Appeared first time on June 15, 2021 (Tuesday) & failed with a very not so good score.
• Re-appeared on June 18, 2021 (Friday) & passed this time with good score.

And here is the Certification ID: 210-093-068, that can be verified here.

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attended community session on client-go informers code walk-through

This friday, I attended a k8s in-dev community session for the client-go informers codebase walk-through.

I was just aware of the term informers as in there is something, some concept, some component known as informers & this falls under the realm of sig-api-machinery. But that is all, what my understanding was before the session!

This session was more of a hacking session, as in both the presenter & the attendees together were trying to decypher stuff written in the codebase (this time for client-go informers). I liked this sort of learning, because it right away set a bar. The bar is not the technical understanding because ofcourse nobody is assuming people would understand the things being discussed beforehand. But the bar is that the session will only make sense & bring value to the people who would care to put in the time & attention & stick until the end.

(And that’s a choice ofcourse.) 🙂

For me, I absolutely learnt a lot.

• The least I know now, what Informers are?
• And the best I know where I could go & look into the huge kubernetes codebase to understand more about it.

We also touched terms like watchers, listwatchers and edge-triggered & level-triggered logics but that’s for me to explore more.

I’m putting all the useful links here for myself (so, I could later on refer them from here)

• edge triggered and level triggered logic
  • https://speakerdeck.com/thockin/edge-vs-level-triggered-logic
  • https://kube.academy/courses/the-kubernetes-machine/lessons/kubernetes-design
  • https://hackernoon.com/level-triggering-and-reconciliation-in-kubernetes-1f17fe30333d
• Stay Informed with Kubernetes Informers
• Extend Kubernetes via a shared informer
  • The example code in the above article was used to write dummy informer. Found very useful!
• Kubernetes API Concepts
• kubernetes/sample-controller ~ pointed during the session for references.
• And lastly, the client-go codebase sits here

The recording for the session could be found here.

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That’s all for my this week!

I would call it a very productive week for me, both during the work & otherwise too.