Templating and Rendering Using Kustomization and Kpt Irvi Aini @irvifa 

Agenda ● Introduction ● Kustomize ● Kpt ● Skaffold ● Demo ● Q&A 

Kustomize https://kubectl.docs.kubernetes.io/references/kustomize 

“kustomize lets you customize raw, template-free YAML files for multiple purposes, leaving the original YAML untouched and usable as is.” This tools is originally sponsored by sig-cli as mentioned in the KEP. TL;DR ● Helps customizing config files in a template free way. ● Provides a number of handy methods like generators to make customization easier, e.g ConfigMap and Secret ● Provides patches to introduce environment specific changes on an already existing standard config file without disturbing the original files Kustomize 

● Create a Kustomization file, this configuration should declare all of the resources that you’d like to apply the configuration over them ● Create variants using overlays, generally speaking an overlay is just another Kustomization file which will be referring to base configuration and additional patches that you’d like to apply for each of the environments Kustomize Usage 

resources - what existing resources are to be customized. Example fields: resources, crds. meta - fields which may influence all or some of the above. Example fields: vars, namespace, apiVersion, kind, etc generators - what new resources should be created. Example fields: configMapGenerator (legacy), secretGenerator (legacy), generators (v2.1). transformers: alter specific bits of your resource definitions. e.g. labels, annotations 

Overlays Base configuration 

Kpt https://goo.gle/kpt 

Original tweet 

For further discussion we will use kpt v1. In general, the 2 fundamentals concept in kpt are: ● Packages. A package is a bundle of configuration data, which is explicitly declare inside of Kptfile. Note that a package can be a part of another package, called as a subpackage. ● Functions. A containerized program that can perform CRUD operations on Kubernetes Resource Model (KRM) resources stored on your local, it also act as a mechanism to automate mutation and validation of KRM resources. Kpt Concepts 

Contains the user-specified Git reference to the upstream package Records the upstream Git reference (exact Git SHA) that was fetched by kpt. This section is managed and should not be changed manually. Modified from: Getting a Package 

Kpt Workflow Create Edit Render Update Initialize Preview Apply Observe Get Modified from Kpt workflow 

Skaffold https://skaffold.dev/ 

Skaffold’s Architecture Skaffold handles the workflow for building, pushing, and deploying your application, and provides building blocks for creating CI/CD pipelines. 

Version of the configuration Project’s identifier Determines how images are tagged. Images that needs to be build, in this case the image is build using jib. Describes how the images are deployed Override for multiple environments. More references can be seen in this page. 

Demo 

jib configuration to build the container kustomize overlays Kptfile Skaffold Sample code is available on irvifa/skaffold-kpt-example 

jib configuration to build the container kustomize overlays Kptfile Skaffold Sample code is available on irvifa/skaffold-kpt-example Where is the Dockerfile?? 

Sample code is available on irvifa/skaffold-kpt-example jib configuration to build the container kustomize overlays Kptfile Skaffold Where is the Dockerfile?? Skaffold ♡ Jib 

Builder: Jib is a set of plugins used or building optimized OCI-compliant container images for Java applications without a Docker daemon. Tagger: inputDigest: if there’s no changes inside the source files then the tag won’t be changed. 

With Jib With Docker Why Jib? 🤔 Jib is already an official builder for Skaffold I’m using Java and since Jib is available I don’t want to care about my Dockerfiles 

Base image Application main class will act as entry point. Ports where the server will be served. 

Resource path for default deployer Default k8s context 

Enable port forwarding so we can call the API from our local 

Port Forwarding Built-in support for forwarding ports from exposed Kubernetes resources to your local machine when running in dev, debug, deploy, or run modes. 

Skaffold dev loop File sync Build Test Deploy If there’s changes on your source code then it will be deployed 

Platinum sponsors: Gold sponsors: 

Organized by: Community partners: 

Thanks! ฅ(＾・ω・＾ฅ) Do you have any questions?