Kubectl get JSONPath Support: Difference between revisions

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{{Internal|JSONPath#.field|JSONPath .''field''}}
{{Internal|JSONPath#.field|JSONPath .''field''}}
The value of a specified field can be obtained with:
The value of a specified field can be obtained with:
 
<syntaxhighlight lang='bash'>
kubectl get pod <pod-name> -o jsonpath="{.status.phase}"
</syntaxhighlight>


====Field Recursive Descent====
====Field Recursive Descent====

Revision as of 02:27, 16 March 2021

External

Internal

Overview

Syntax

$

Element Selection

Object Fields Selection

Individual Fields

JSONPath .field

The value of a specified field can be obtained with:

kubectl get pod <pod-name> -o jsonpath="{.status.phase}"

Field Recursive Descent

All values for a specific field can be obtained recursively with:

JSONPath ..field (field recursive descent)

Array Element Selection

Wildcard

@

Filter Expressions

[?(expression)]
JSONPath Filter Expressions

Organizatorium

Removing Leading and Trailing Single Quotes

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

Get an Individual Attribute Only

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


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}'