JSONPath

Part of the Introduction to Kubernetes section of Coddy's Terminal journey. Lesson 36 of 45.

Often you want one value, not the whole object. -o jsonpath picks fields out of the object with a path expression, written between braces:

kubectl get pod web -o jsonpath='{.status.podIP}'

This prints just the Pod's IP. The path follows the YAML structure: status, then podIP.

Lists are indexed with square brackets. The first container's image is:

kubectl get pod web -o jsonpath='{.spec.containers[0].image}'

For a list of objects, .items[*] selects every item, so kubectl get pods -o jsonpath='{.items[*].metadata.name}' prints all the Pod names on one line.

jsonpath prints exactly what you ask for, without a newline at the end. Add {"\n"} inside the braces when you want one.

Challenge

Easy

Start a Pod named web from the nginx image, then use jsonpath to print its IP address, and jsonpath again to print the image of its first container.

Try it yourself

Terminal