Implementing a Mutating Admission Webhook
Learn how to implement a mutating admission webhook service.
Implement a mutating admission webhook service
A mutating 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 /mutate over port 443. It adds labels for Pods. Below is the development environment in which we can add and modify our programs. We can click the “Run” button to initialize it.
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Mutating admission webhook
In a real-world scenario, we only need to replace the mock code in the function admit() (line 21 in main.go) with our actual business logic. In the demo above, we’re handling pods, and other resources can be handled as well ...
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