When I started at Transreport, I set up Helm charts for Passenger Assist, to make our deployments easier to set up. In hindsight, it was also a really good way to get to know the company’s products, because to set the Helm charts up, I needed a good understanding of the architecture, and what needs to happen for the program to run.
Working with Kubernetes requires the use of kubectl, a great command line tool that lets you interact with Kubernetes’ API. However, using kubectl gets repetitive pretty quickly, especially if you’re working with namespaces; I regularly run commands like these:
aws eks update-kubeconfig --name <passenger-assist-production-cluster-name>
kubectl get pods -n sqr-emr-staging
kubectl get pod -n pa-staging <pod-name> -o yaml
kubectl describe configmap -n sqr-emr-uat
To save time, and to reduce the chance of making a typo, I’ve set up a few aliases, allowing me to replace those commands with:
kswitchprodpa
kgn po
kgyn po <pod-name>
kdn cm
I (on my Ubuntu 18 OS) use aliases to speed my Kubernetes work up drastically. To avoid writing kubectl, I added
alias k='kubectl'
to my ~/.bashrc file. Every time I open a new terminal, it runs every line in my ~/.bashrc file, which will now replace the letter k with kubectl, if I write it at the beginning of a command. Note that any already-open terminals won’t respond to changes in the ~/.bashrc file, unless you run source ~/.bashrc.
Here are some standard kubectl commands that I replaced:
alias k='kubectl'
alias ka='kubectl apply'
alias kl='kubectl logs'
alias ke='kubectl edit'
alias krm='kubectl delete'
alias kd='kubectl describe'
alias keit='kubectl exec -it'
alias kg='kubectl get'
alias kgsys='kubectl get -n kube-system'
alias wkg='watch kubectl get'
alias kgy='kubectl get -o yaml'
alias kwhere='kubectl config current-context'
Kubernetes uses namespaces to group resources together, and isolate them from other groups. kubectl lets you select the namespace you’re interested in by adding -n <namespace-name> to your kubectl command. However, most of the time, you’ll need to run several commands in the same namespace, so adding -n <namespace-name> gets pretty tedious, especially when namespaces have long names. That’s why I’ve set up these aliases:
alias padev='KUBE_NAMESPACE=pa-dev'
alias pastaging='KUBE_NAMESPACE=pa-staging'
### There's a whole lot more of these
and
alias kln='kubectl logs -n $KUBE_NAMESPACE'
alias ken='kubectl edit -n $KUBE_NAMESPACE'
alias krmn='kubectl delete -n $KUBE_NAMESPACE'
alias kdn='kubectl describe -n $KUBE_NAMESPACE'
alias keitn='kubectl exec -it -n $KUBE_NAMESPACE'
alias kgn='kubectl get -n $KUBE_NAMESPACE'
alias wkgn='watch kubectl get -n $KUBE_NAMESPACE'
alias kgyn='kubectl get -o yaml -n $KUBE_NAMESPACE'
Now, simply adding an n to the end of my standard kubectl shortcuts stops me from accidentally writing -n pa-aut and -n sqr-emr=staging multiple times a day.
At Transreport, we use Terraform to create our EKS clusters, and to avoid naming clashes, their names have randomised strings at the ends. It’s annoying to have to learn them, so instead, I have these aliases set up:
alias kswitchnonprodpa='aws eks update-kubeconfig --name <name-of-eks-cluster>>'
alias kswitchprodpa='aws eks update-kubeconfig --name <name-of-eks-cluster>>'
alias kswitchnonprodcommon='aws eks update-kubeconfig --name <name-of-eks-cluster>>'
alias kswitchprodcommon='aws eks update-kubeconfig --name <name-of-eks-cluster>>'
Helm is essentially a Kubernetes package manager, and its command line tool, helm, works pretty similarly to kubectl, in terms of using namespaces. Use the same trick:
alias helmn='helm -n $KUBE_NAMESPACE`
alias helmlsn='helm ls -n $KUBE_NAMESPACE`
alias helmgvn='helm get values -n $KUBE_NAMESPACE`
alias helmtp='helm template --output-dir .`
alias helmtpn='helm template --output-dir . -n $KUBE_NAMESPACE`
alias helmsearch='helm search repo' ### Avoid getting it wrong and typing helm repo search every time.
Other helm commands like helm install probably deserve the time taken to type the command out.
Do yourself a favour and never write terrafrom again:
alias tf='terraform'
alias tfi='terraform init'
alias tfws='terraform workspace'
alias tfwsl='terraform workspace list'
alias tfs='terraform state'
alias tfsl='terraform state list'
alias tfp='terraform plan'
alias tfa='terraform apply'
alias tfaa='terraform apply -auto-approve' --> Don't use this unless you're a #madlad