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ConfigMap

ConfigMap are used to store configuration data. They provide a dictionary based data structure that can be consumed in various shapes and forms.

Use an existing ConfigMap

You can reference to an existing ConfigMap like so. Note that this does not create a new object, and will therefore not be included in the resulting manifest.

import * as kplus from 'cdk8s-plus-29';
import { Construct } from 'constructs';
import { App, Chart, ChartProps } from 'cdk8s';

export class MyChart extends Chart {
  constructor(scope: Construct, id: string, props?: ChartProps) {
    super(scope, id, props);

    const config: kplus.IConfigMap = kplus.ConfigMap.fromConfigMapName(this, 'ConfigMap', 'config');

    // the 'config' constant can later be used by API's that require an IConfigMap.
    // for example when creating a volume.
    kplus.Volume.fromConfigMap(this, 'Volume', config);
  }
}

const app = new App();
new MyChart(app, 'VolumeFromConfigMap');
app.synth();

Adding data

You can create config maps and add some data to them like so:

import * as kplus from 'cdk8s-plus-29';
import { Construct } from 'constructs';
import { App, Chart, ChartProps } from 'cdk8s';

export class MyChart extends Chart {
  constructor(scope: Construct, id: string, props?: ChartProps) {
    super(scope, id, props);

    const config = new kplus.ConfigMap(this, 'Config');
    config.addData('url', 'https://my-endpoint:8080');
  }
}

const app = new App();
new MyChart(app, 'ConfigMap');
app.synth();

Creating a volume from a directory

Here is a nifty little trick you can use to create a volume that contains a directory on the client machine (machine that runs cdk8s synth):

import * as kplus from 'cdk8s-plus-29';
import * as path from 'path';
import { Construct } from 'constructs';
import { App, Chart, ChartProps } from 'cdk8s';

export class MyChart extends Chart {
  constructor(scope: Construct, id: string, props?: ChartProps) {
    super(scope, id, props);
    const appMap = new kplus.ConfigMap(this, 'Config');

    // add the files in the directory to the config map.
    // this will create a key for each file.
    // note: this directory needs to exist
    // note: that only top level files will be included, sub-directories are not yet supported.
    appMap.addDirectory(path.join(__dirname, 'app'));

    const appVolume = kplus.Volume.fromConfigMap(this, 'ConfigMap', appMap);

    const mountPath = '/var/app';
    const pod = new kplus.Pod(this, 'Pod');
    const container = pod.addContainer({
      image: 'node',
      command: [ 'node', 'app.js' ],
      workingDir: mountPath,
    });

    // from here, just mount the volume to a container, and run your app!
    container.mount(mountPath, appVolume);
  }
}

const app = new App();
new MyChart(app, 'AppWithDir');
app.synth();