Kubectl get JSONPath Support: Difference between revisions

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* [[JSONPath#.field|JSONPath .''field'']]
* [[JSONPath#.field|JSONPath .''field'']]
* [[JSONPath#..field_.28Field_Recursive_Descent.29|JSONPath ..''field'' (field recursive descent)]]
* [[JSONPath#..field_.28Field_Recursive_Descent.29|JSONPath ..''field'' (field recursive descent)]]
===Array Element Selection===
===Array Element Selection===
* [[JSONPath#.5B0-based-index.5D|[''0-based-index'']]]
* [[JSONPath#.5B0-based-index.5D|[''0-based-index'']]]
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* [[JSONPath#.5B:n.5D|[:''n'']]]
* [[JSONPath#.5B:n.5D|[:''n'']]]
* [[JSONPath#.5B-n:.5D|[-''n'':]]]
* [[JSONPath#.5B-n:.5D|[-''n'':]]]
===* (Wildcard)===
* [[JSONPath#.2A_.28Wildcard.29|* (wildcard)]]


=Concepts=
=Concepts=

Revision as of 02:17, 16 March 2021

External

Internal

Overview

Syntax

$

Element Selection

Object Fields Selection

Array Element Selection

* (Wildcard)

Concepts

Syntax Elements

Removing Leading and Trailing Single Quotes

... | sed -e 's/^'\''//' > ...

Get an Individual Attribute Only

TODO: https://gist.github.com/so0k/42313dbb3b547a0f51a547bb968696ba

kubectl ... -o jsonpath="{.status.phase}"
kubectl ... -o jsonpath="{.items[?(@.spec.unschedulable)].metadata.name}"

Alternative, to explore and document:

kubectl get pods  --no-headers -o custom-columns=\":metadata.name\" ...

Filter Elements of an Array based on a Key Value

We assume that the elements of the array are maps, which contain the specified key:

kubectl ... -o jsonpath="{.users[?(@.name=="blue")].user.password}"
kubectl get pod ... -o jsonpath='{.items[0].spec.volumes[?(@.name=="vault")].hostPath.path}' 2>/dev/null

Select and Combine Two or More Elements

kubectl get pod \
-o jsonpath='{.items[0].spec.volumes[?(@.name=="A")].hostPath.path}'+'{.items[0].spec.volumes[?(@.name=="B")].hostPath.path}'

returns "/some/path/a+/some/path/b"

Same Element from Multiple Resources

kubectl get pod -o jsonpath='{.items[*].metadata.name}'

Array Length

jq Array Length

TODO

kubectl get pods -o=jsonpath='{.items[?(@.metadata.labels.name=="web")].metadata.name}'
Iterate over the Elements of an Array
kubectl get nodes -o jsonpath='{.items[*]}'
Iterate over the Elements of an Array and Select a Specific Key
kubectl get nodes -o jsonpath='{.items[*].status}'

Filter by an element:

kubectl get nodes -o jsonpath='{.items[*].status.addresses[?(@.type=="InternalIP")]}'

Print the element "address"

kubectl get nodes -o jsonpath='{.items[*].status.addresses[?(@.type=="InternalIP")].address}'