Kubectl get JSONPath Support: Difference between revisions

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==Element Selection==
==Element Selection==
===Object Fields Selection===
===Object Fields Selection===
* [[JSONPath#.field|JSONPath .''field'']]
====Individual Fields====
* [[JSONPath#..field_.28Field_Recursive_Descent.29|JSONPath ..''field'' (field recursive descent)]]
{{Internal|JSONPath#.field|JSONPath .''field''}}
The value of a specified field can be obtained with:
 
 
====Field Recursive Descent====
All values for a specific field can be obtained recursively with:
{{Internal|JSONPath#..field_.28Field_Recursive_Descent.29|JSONPath ..''field'' (field recursive descent)}}
 
===Array Element Selection===
===Array Element Selection===
* [[JSONPath#.5B0-based-index.5D|JSONPath [''0-based-index'']]]
* [[JSONPath#.5B0-based-index.5D|JSONPath [''0-based-index'']]]

Revision as of 02:26, 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:


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="{.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}'