kubebuilder VS flux2

The Spin operator uses the Kubebuilder framework and contains a Spin App Custom Resource Definition (CRD) and controller. It watches Spin App Custom Resources and realizes the desired state in the K8s cluster. Aside from the immediate benefits gained by running Wasm workloads in k8s, additional optimizations such as Horizontal Pod Scaling (HPA) and k8s Event-driven Autoscaling (KEDA) can be achieved in a pinch.

kubebuilder: brew install kubebuilder

The operator that I've been working on is designed to manage the full lifecycle of a QuestDB database instance, including version and hardware upgrades, config changes, backups, and (eventually) recovery from node failure. I used the Operator SDK and kubebuilder frameworks to provide scaffolding and API support.

Recently, I've been spending a lot of time writing a Kubernetes operator using the go operator-sdk, which is built on top of the Kubebuilder framework. This is a list of a few tips and tricks that I've compiled over the past few months working with these frameworks.

Since we built our operator using the Kubebuilder framework, most standard monitoring tasks were handled for us out-of-the-box. Our operator automatically exposes a rich set of Prometheus metrics that measure reconciliation performance, the number of k8s API calls, workqueue statistics, and memory-related metrics. We we were able to ingest these metrics into pre-built dashboards by leveraging the grafana/v1-alpha plugin, which scaffolds two Grafana dashboards to monitor Operator resource usage and performance. All we had to do was add these to our existing Grafana manifests and we were good to go!

I wrote a CSI driver and some operators. I admire K8s, because you can find solution to almost any problem in the source code - API versioning, load balancing, request throttling, optimistic concurrency, security, and much much more. I recommend https://book.kubebuilder.io/ It is similar to Operator SDK, but without Openshift-specific stuff. It gradually introduces you to many k8s concepts, and follows design patterns that k8s uses internally.

Do you mean this: https://book.kubebuilder.io/ ?

https://book.kubebuilder.io/ all you need to know

A better way to write an operator these days is to use kubebuilder [1].

My complaint is that I have seen orgs write operators for random stuff, often reinventing the wheel. Lot of operators in orgs are result of resume driven development. Having said that it often comes handy for complex orchestration.

[1]https://github.com/kubernetes-sigs/kubebuilder

Given the team had already adopted GitOps and were familiar with deployments powered by Helm Releases and Flux, we wanted to move the provisioning of the infrastructure to be part of the same process of creating the service and its continuous deployment.

Your GitHub action can trigger a helm chart, or series thereof, or other infra tools. Declarative specifications, triggered procedurally with the context of the branch’s latest build. We use this pattern quite extensively for preview app workflows.

As of a year ago this is possible in a fully declarative way with Flux 2, but there’s a lot more moving parts and security footguns - and the idea that the maintenance of this project has lost one of its primary sponsors is worrying at best.

https://github.com/fluxcd/flux2/discussions/831

https://blog.kluctl.io/introducing-the-template-controller-a...

FluxCD - FluxCD is another popular GitOps tool that allows developers to use a Git repository as the sole source of configuration. Flux automatically ensures that the state of the Kubernetes cluster is synchronized with the configuration in the Git repository. It supports automatic updates, meaning Flux can monitor Docker image repositories for new images and push updates to the cluster.

#!/bin/bash aws eks update-kubeconfig --name $CLUSTER_NAME --region $AWS_REGION flux_installed=$(kubectl api-resources | grep flux) if [ -z "$flux_installed" ]; then echo "flux is not installed" curl -s https://fluxcd.io/install.sh | sudo bash flux bootstrap github \ --owner=$GH_USER_NAME \ --repository=$FLUX_REPO_NAME \ --path="clusters/$ENVIRONMENT/$CLUSTER_NAME/bootstrap" \ --branch=main \ --personal else echo "flux is installed" fi

Flux CD enables continuous deployment to Kubernetes through GitOps by syncing Git repositories with Kubernetes clusters. Flux CD enables GitOps for Kubernetes through source control integration. It manages Kubernetes manifests as code and syncs git repo changes to clusters. Flux automates checks, deployments, and updates within clusters.

FluxCD is a GitOps tool developed by Weaveworks that allows you to implement continuous and progressive delivery of your applications on Kubernetes. It is a CNCF graduated project that offers a set of controllers to monitor Git repositories and reconciles the cluster's actual state with the desired state defined by manifests committed in the repo.

From here, we can explore other developments and tutorials on Kubernetes, such as o11y or observability (PLG, ELK, ELF, TICK, Jaeger, Pyroscope), service mesh (Linkerd, Istio, NSM, Consul Connect, Cillium), and progressive delivery (ArgoCD, FluxCD, Spinnaker).

Instead, we will create a single long-lived cluster, and deploy our application in different namespaces. There are a bunch of ways to do that - see ArgoCD, Flux, custom internal tooling, or other solutions (we use our own product). That way, we:

One is to make sure configurations in both clusters is same. And for that there are many tools like fluxcd or projectsveltos