Kubernetes ConfigMap Operations: Difference between revisions

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* [[Kubernetes Operations#ConfigMap_Operations|Kubernetes Operations]]
* [[Kubernetes Operations#ConfigMap_Operations|Kubernetes Operations]]
* [[Kubernetes_Cluster_Configuration_Concepts#ConfigMap|Kubernetes Cluster Configuration Concepts]]
* [[Kubernetes_Cluster_Configuration_Concepts#ConfigMap|Kubernetes Cluster Configuration Concepts]]
=List ConfigMaps in a Namespace=
<syntaxhighlight lang='bash'>
kubectl -n <namespace-name> get configmaps
</syntaxhighlight>


=Inspect a ConfigMap=
=Inspect a ConfigMap=
 
<syntaxhighlight lang=bash>
kubectl get cm <''name''> -o yaml
kubectl get cm <cm-name> -o yaml
 
kubectl describe cm <cm-name>
</syntaxhighlight>
<syntaxhighlight lang=yaml>
<syntaxhighlight lang=yaml>
apiVersion: v1
apiVersion: v1
Line 21: Line 27:


=Read the Content of a File Stored in ConfigMap=
=Read the Content of a File Stored in ConfigMap=
 
<syntaxhighlight lang=bash>
kubectl get cm <''configmap-name''> -o jsonpath='{.data.<''key''>}'
kubectl get cm <cm-name> -o jsonpath='{.data.<''key''>}'
</syntaxhighlight>


=Create a ConfigMap with CLI=
=Create a ConfigMap with CLI=
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The entire content of the file is keyed by default under the file name.
The entire content of the file is keyed by default under the file name.
<syntaxhighlight lang='bash'>
<syntaxhighlight lang='bash'>
kubectl create configmap example --from-file=some-config-file.txt
kubectl create configmap <cm-name> --from-file=some-config-file.txt [--from-file=some-config-file2.txt ...]
</syntaxhighlight>
</syntaxhighlight>


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An arbitrary key, different from the file name, can be specified:
An arbitrary key, different from the file name, can be specified:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang='bash'>
kubectl create configmap example --from-file=mykey=some-config-file.txt
kubectl create configmap <cm-name> --from-file=mykey=some-config-file.txt
</syntaxhighlight>
</syntaxhighlight>
Multiple <code>--from-file=</code> can be used.
Multiple <code>--from-file=</code> can be used.
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==Interactively==
==Interactively==
<syntaxhighlight lang='bash'>
<syntaxhighlight lang='bash'>
kubectl edit configmap myconfigmap
kubectl edit configmap <cm-name>
</syntaxhighlight>
</syntaxhighlight>
==Non-Interactively==
==Non-Interactively==


This sequence adds a key/value (shape=square) to an existing ConfigMap, leaving the other keys unchanged:
This sequence adds a key/value (shape=square) to an existing ConfigMap, leaving the other keys unchanged:
<syntaxhighlight lang='bash'>
<syntaxhighlight lang='bash'>
  kubectl create configmap <''existing-configmap-name''> --from-literal=shape=square --dry-run --save-config=true -o yaml | k apply -f -
  kubectl create configmap <existing-configmap-name> --from-literal=shape=square --dry-run --save-config=true -o yaml | k apply -f -
</syntaxhighlight>
</syntaxhighlight>

Latest revision as of 17:18, 29 February 2024

External

Internal

List ConfigMaps in a Namespace

kubectl -n <namespace-name> get configmaps

Inspect a ConfigMap

kubectl get cm <cm-name> -o yaml
kubectl describe cm <cm-name>
apiVersion: v1
kind: ConfigMap
metadata:
  name: example
  ...
data:
  color: red
  shape: square

Read the Content of a File Stored in ConfigMap

kubectl get cm <cm-name> -o jsonpath='{.data.<''key''>}'

Create a ConfigMap with CLI

All three options presented below can be combined on one single command line:

Specify Key/Value Pairs on Command Line

kubectl create configmap example \
  --from-literal=COLOR=red \
  --from-literal=SHAPE=square \
  --from-literal=PHRASE="something and something else"

Multiple --from-literal= entries are allowed.

Use the Content of a File

The entire content of the file is keyed by default under the file name.

kubectl create configmap <cm-name> --from-file=some-config-file.txt [--from-file=some-config-file2.txt ...]
apiVersion: v1
kind: ConfigMap
metadata:
  name: example
  ...
data:
  some-config-file.txt: |
    color=blue
    shape=circle

An arbitrary key, different from the file name, can be specified:

kubectl create configmap <cm-name> --from-file=mykey=some-config-file.txt

Multiple --from-file= can be used.

Import all Files from a Directory

kubectl can be used to inspect a directory and create an individual ConfigMap entry for each file in the directory whose name is a valid ConfigMap key. In the example below, /tmp/config-dir contains two files: A.txt and B.txt.

kubectl create configmap example --from-file=/tmp/config-dir
apiVersion: v1
kind: ConfigMap
metadata:
  name: example
  ...
data:
  A.txt: |
    color=red
  B.txt: |
    shape=square

Edit an Already Deployed ConfigMap

Interactively

kubectl edit configmap <cm-name>

Non-Interactively

This sequence adds a key/value (shape=square) to an existing ConfigMap, leaving the other keys unchanged:

 kubectl create configmap <existing-configmap-name> --from-literal=shape=square --dry-run --save-config=true -o yaml | k apply -f -