How do I store configuration data using Kubernetes ConfigMap patches?

In this guide, we will learn how to store and manage configuration data using Kubernetes ConfigMap patches in Pulumi. ConfigMaps are used to store configuration data in key-value pairs, which can be consumed by your Kubernetes applications. Patching a ConfigMap allows you to update specific parts of the configuration without modifying the entire ConfigMap.

Key Points

• ConfigMap: A Kubernetes object used to store non-confidential data in key-value pairs.
• Patch: An update to a specific part of a resource without modifying the entire resource.

Below is a Pulumi program in TypeScript that demonstrates how to create a ConfigMap and then apply a patch to it.

import * as pulumi from "@pulumi/pulumi";
import * as k8s from "@pulumi/kubernetes";

// Create a Kubernetes ConfigMap
const configMap = new k8s.core.v1.ConfigMap("example-configmap", {
    metadata: {
        name: "example-configmap",
        namespace: "default",
    },
    data: {
        "configKey1": "initialValue1",
        "configKey2": "initialValue2",
    },
});

// Apply a patch to the existing ConfigMap
const configMapPatch = new k8s.core.v1.ConfigMapPatch("example-configmap-patch", {
    metadata: {
        name: "example-configmap",
        namespace: "default",
    },
    data: {
        "configKey1": "updatedValue1",
    },
}, { dependsOn: configMap });

// Export the name of the ConfigMap
export const configMapName = configMap.metadata.name;

Summary

In this program, we first create a ConfigMap named example-configmap with some initial configuration data. We then create a ConfigMapPatch to update the value of configKey1 in the existing ConfigMap. The dependsOn option ensures that the patch is applied only after the initial ConfigMap is created.

By using ConfigMap patches, you can manage updates to your configuration data efficiently without needing to recreate the entire ConfigMap. This approach is useful for maintaining configuration consistency and reducing the risk of errors during updates.