A ConfigMap stores key-value pairs that your applications can use as environment variables or mounted files. Unlike secrets, ConfigMaps are meant for non-sensitive data. Moreover, you can update configurations without modifying or rebuilding your container images, thus making the deployments more efficient.
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Go to the Configurations → Base Configurations.
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Click the + button next to ConfigMaps.
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Data Type - Choose between the following data types:
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Select Kubernetes ConfigMap as the Data Type.
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Name - Provide a name to your ConfigMap (cannot be changed later).
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Mount data as - Select how you want to mount the ConfigMap:
- Environment Variable – Select this option if you want to inject Environment Variables in pods using ConfigMap.
- Data Volume – Select this option, if you want to configure a Data Volume that is accessible to Containers running in a pod and provide a Volume mount path. Go to Data Volume to know more.
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Enter data in:
- GUI mode – User-friendly interface. Click +Add button and enter the Key and Value fields without quotes.
- YAML mode – Raw YAML for entering key-value pairs in the format
key: value. Boolean and numeric values must be wrapped in double quotes.
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You may perform a dry run before clicking Save.
Use this option if you have a ConfigMap created using the kubectl command. Ensure that the External ConfigMap exists and is available to the pod.
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Select Kubernetes External ConfigMap as the Data Type.
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Name - Since you are using Kubernetes External ConfigMap, make sure you give the name of ConfigMap the same as the name given using
kubectl create configmap <configmap-name> <data source>command, otherwise, it might result in an error during the build. -
Mount data as: Environment Variable or Data Volume
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Click Save.
In the above example, we have seen how to pass environment variables in your ConfigMap. Additionally, there is an option to create a ConfigMap by passing the content of a file. The content could be a plain text, json, yaml, bash script, etc. You can do so by selecting the Data Volume option in Mount data as.
The key of the ConfigMap should be your filename and the value of the ConfigMap should be your file content. In the below example, you file.json is the key, and the json content is the value of that ConfigMap (below the pipe (|) symbol). This file will be created on your specified volume mount path.
Enter the folder path where the data volume should be mounted for it to be accessible to the containers running in a pod. Your keys will be mounted as files to that volume.
When mounting multiple files to the same location, you can use the Set Sub Path option to control how the files are handled. This setting allows you to control whether existing files are overwritten or preserved when mounting new files.
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If Set Sub Path is enabled, the system will preserve existing files in the specified path and append the new file using the file name as a sub-path.
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If Set Sub Path is disabled (unchecked), the system will delete any files already present in the specified path and then mount the new files.
{% hint style="info" %}
In case of Kubernetes ConfigMap, all keys will be mounted as files on the specified path. In case of Kubernetes External ConfigMap, manually specify the keys which should be mounted as files. {% endhint %}
The Set File Permission option applies permissions at the ConfigMap level, not to individual keys within the ConfigMap. Enabling this option will let you enter a 3-digit standard permission value to control access to the file.
The 3-digit numeric value represents the permission settings for the file:
- First digit: Owner permissions (user).
- Second digit: Group permissions.
- Third digit: Other users' permissions.
| Permission | Description |
|---|---|
| r (read) | Grants the ability to read the file. |
| w (write) | Grants the ability to modify the file. |
| x (execute) | Grants the ability to execute the file as a program. |
For example, 755 means:
- Owner can read, write, and execute (7),
- Group can read and execute (5),
- Others can read and execute (5).
Before saving your configured ConfigMap, you can use the Dry Run option (as shown below) to preview the final Kubernetes manifest.
This feature helps you verify your configurations, detect issues, and ensure correctness.
Your configurations will appear in the left pane, while the right pane will display a section named Manifest generated from merged showing the computed Kubernetes manifest.
- Click your ConfigMap available inside the list of ConfigMaps inside Base Configurations.
- Modify its values.
- Click Update.
{% hint style="warning" %}
You cannot change the name of a ConfigMap. Create a new ConfigMap instead. {% endhint %}
You may delete a ConfigMap if not in use anymore. Once a ConfigMap is deleted, it will not be used in future deployments.
- Click your ConfigMap available inside the list of ConfigMaps inside Base Configurations.
- On the right side, click the kebab menu (3 vertical dots).
- Click Delete.
- Confirm the deletion in the dialogbox.
Any changes made to the protected base configurations (Deployment Template, ConfigMap, Secret) will require approval if an approval policy is enforced.
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