Creating a ConfigMap

Scenario

A ConfigMap is a type of resource that stores configuration information required by a workload. Its content is user-defined. After creating ConfigMaps, you can use them as files or environment variables in a containerized workload.

ConfigMaps allow you to decouple configuration files from container images to enhance the portability of workloads.

Benefits of ConfigMaps:

Manage configurations of different environments and services.
Deploy workloads in different environments. Multiple versions are supported for configuration files so that you can update and roll back workloads easily.
Quickly import configurations in the form of files to containers.

Constraints

The size of a ConfigMap resource file cannot exceed 1 MB.
ConfigMaps cannot be used in static pods.

Procedure

Log in to the CCE console and click the cluster name to access the cluster console.
Choose ConfigMaps and Secrets in the navigation pane and click Create ConfigMap in the upper right corner.

Configure parameters.

**Table 1** Parameters for creating a ConfigMap
Parameter	Description
Name	Name of the ConfigMap you create, which must be unique in a namespace.
Namespace	Namespace to which the ConfigMap belongs. If you do not specify this parameter, the value default is used by default.
Description	Description of the ConfigMap.
Data	Data of a ConfigMap, in the key-value pair format. Click to add data. The value can be in string, JSON, or YAML format.
Label	Label of the ConfigMap. Enter a key-value pair and click Confirm.

Click OK.
The new ConfigMap is displayed in the ConfigMap list.

Creating a ConfigMap Using kubectl

Use kubectl to connect to the cluster. For details, see Connecting to a Cluster Using kubectl.

Create a file named cce-configmap.yaml and edit it.

vi cce-configmap.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: cce-configmap
data:
  SPECIAL_LEVEL: Hello
  SPECIAL_TYPE: CCE

**Table 2** Key parameters
Parameter	Description
apiVersion	The value is fixed at v1.
kind	The value is fixed at ConfigMap.
metadata.name	ConfigMap name, which can be customized.
data	ConfigMap data. The value must be key-value pairs.

Run the following commands to create a ConfigMap.
kubectl create -f cce-configmap.yaml

Run the following commands to view the created ConfigMap:

kubectl get cm
```
NAME               DATA            AGE
cce-configmap      3               7m
```

Related Operations

After creating a ConfigMap, you can update or delete it as described in Table 3.

**Table 3** Related operations
Operation	Description
Editing a YAML file	Click Edit YAML in the row where the target ConfigMap resides to edit its YAML file.
Updating a ConfigMap	Select the name of the ConfigMap to be updated and click Update. Modify the secret data. For more information, see Table 1. Click OK.
Deleting a ConfigMap	Select the configuration you want to delete and click Delete. Follow the prompts to delete the ConfigMap.