Mount ConfigMaps

Mount Kubernetes ConfigMaps into workspace containers to provide non-sensitive configuration data.

Before you begin

  • You have an active oc session with your project. See Getting started with the CLI. Warning

    By default, applying a ConfigMap with the controller.devfile.io/mount-to-devworkspace: 'true' label restarts all running workspaces in the project. To mount the ConfigMap only at workspace start and prevent automatic restarts, add the controller.devfile.io/mount-on-start: 'true' annotation.

Procedure

  1. Create a ConfigMap with the required labels and annotations: 
    kind: ConfigMap
apiVersion: v1
metadata:
  name: my-config
  labels:
    controller.devfile.io/mount-to-devworkspace: 'true'
    controller.devfile.io/watch-configmap: 'true'
  annotations:
    controller.devfile.io/mount-as: file
    controller.devfile.io/mount-path: /etc/my-config
data:
  settings.json: |
    {
      "editor.fontSize": 14,
      "editor.tabSize": 2
    }

    where:

    controller.devfile.io/mount-to-devworkspace
    Required label to mount the ConfigMap to all workspaces.
    controller.devfile.io/watch-configmap
    Watch the ConfigMap for changes and update mounted files.
    controller.devfile.io/mount-as
    Mount type: file, subpath, or env.
    controller.devfile.io/mount-path
    Path where the ConfigMap data is mounted.
  2. Apply the ConfigMap to your project: 
    $ oc apply -f my-config.yaml -n <your_namespace>
  3. Optional: Add annotations to the ConfigMap to customize the mounting behavior.
    Expand
    Table 1. ConfigMap mounting annotations
    Annotation Description

    controller.devfile.io/mount-path: <path>

    Overrides the default mount path. The default mount path is /etc/config/<ConfigMap_name>.

    controller.devfile.io/mount-as: file

    Each key in the ConfigMap data becomes a file in the mount path directory.

    controller.devfile.io/mount-as: subpath

    Similar to file, but uses subPath volumes for better compatibility.

    controller.devfile.io/mount-as: env

    Each key-value pair becomes an environment variable in all workspace containers.

    controller.devfile.io/mount-on-start: 'true'

    When set to true, the ConfigMap is mounted only when a workspace starts, not while it is already running. This prevents workspace restarts when the ConfigMap is created.

    controller.devfile.io/mount-to-devworkspace-include:

    Specifies a comma-separated list of Dev Workspace name patterns. When set, the ConfigMap is mounted only to workspaces whose names match at least one pattern.

    controller.devfile.io/mount-to-devworkspace-exclude:

    Specifies a comma-separated list of Dev Workspace name patterns. When set, the ConfigMap is mounted to all workspaces except those whose names match a pattern.
    Note

    When both controller.devfile.io/mount-to-devworkspace-include and controller.devfile.io/mount-to-devworkspace-exclude annotations are set, the ConfigMap is mounted only to workspaces that match the include pattern and do not match the exclude pattern.

    For example, to mount ConfigMap data as environment variables:

    kind: ConfigMap
apiVersion: v1
metadata:
  name: my-env-config
  labels:
    controller.devfile.io/mount-to-devworkspace: 'true'
    controller.devfile.io/watch-configmap: 'true'
  annotations:
    controller.devfile.io/mount-as: env
data:
  LOG_LEVEL: debug
  MAX_CONNECTIONS: "100"
  4. Start or restart your workspace to apply the mounted ConfigMap.

Results

  • For file or subpath mounts, verify the ConfigMap data is available at the mount path: 
    $ cat /etc/my-config/settings.json
  • For env mounts, verify the environment variables are set: 
    $ echo $LOG_LEVEL