Implementing a Validating Admission WebHook
Learn how to implement a validating admission webhook service.
Implement a validating admission webhook
A validating admission webhook service is a web server, because the kube-apiserver invokes it through HTTPS POST requests. Now, let’s implement such a service step by step.
Step 1: Write a simple HTTP server
Let’s write a simple HTTP server at the path /validate on port 443. It checks the Pod name and rejects all Pods having mock-app in their names. The development environment that we can use to add and modify our programs is given below. We can hit the “Run” button to initialize it.
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Our development environment
In a real-world scenario, we only need to replace the mock code in the function validate() (line 21 in main.go) with our actual business logic. In the demo above, we’re handling Pods, and ...
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