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Version: 2.8.x(Latest)

Kubernetes ConfigMap Configuration Example

Github Source: https://github.com/gogf/examples/tree/main/config/kubecm

Description​

This directory contains an example demonstrating how to integrate Kubernetes ConfigMap with GoFrame applications for configuration management. It shows:

  1. Kubernetes Client Configuration

    • In-Pod configuration setup
    • Out-of-Pod configuration setup
    • ConfigMap access and management
    • Error handling and logging

  2. Configuration Management

    • Configuration loading and parsing
    • Dynamic configuration updates
    • Configuration value retrieval

Directory Structure​

.
├── boot_in_pod/     # Bootstrap configuration for in-pod deployment
│   └── boot.go      # In-pod client initialization
├── boot_out_pod/    # Bootstrap configuration for out-of-pod deployment
│   └── boot.go      # Out-of-pod client initialization
├── main.go          # Main application entry
├── go.mod           # Go module file
└── go.sum           # Go module checksums

Requirements​

Features​

The example showcases the following features:

  1. Kubernetes Integration

    • In-Pod configuration
    • Out-of-Pod configuration
    • ConfigMap management
    • Error handling

  2. Configuration Management

    • Configuration loading
    • Value retrieval
    • Type conversion
    • Default values

  3. Dynamic Updates

    • Configuration watching
    • Change notification
    • Hot reload support

Configuration​

Kubernetes Setup​

  1. Cluster Configuration:

    • Kubernetes cluster access
    • Namespace management
    • RBAC permissions

  2. ConfigMap Setup:

    • ConfigMap creation
    • Data item management
    • Access control

Client Configuration​

  1. In-Pod Settings:

    • Automatic service account
    • ConfigMap name
    • Data item name

  2. Out-of-Pod Settings:

    • KubeConfig path
    • Namespace selection
    • Client configuration
    • Access permissions

Usage​

  1. Create ConfigMap:

    # Create a ConfigMap with configuration data
    kubectl create configmap test-configmap --from-file=config.yaml=./config.yaml

  2. Configure Access:

    # Ensure proper RBAC permissions
    kubectl create role config-reader --verb=get,list,watch --resource=configmaps
    kubectl create rolebinding config-reader-binding --role=config-reader --serviceaccount=default:default

  3. Run Example:

    # For in-pod deployment
    go run main.go

    # For out-of-pod deployment (local development)
    KUBE_CONFIG=~/.kube/config go run main.go

Implementation Details​

  1. In-Pod Setup (boot_in_pod/boot.go):

    • Simple configuration for in-pod deployment
    • Automatic service account usage
    • Minimal configuration required

  2. Out-of-Pod Setup (boot_out_pod/boot.go):

    • External cluster access configuration
    • KubeConfig file usage
    • Namespace specification
    • Custom client configuration

  3. Configuration Access (main.go):

    • Configuration availability check
    • Bulk configuration retrieval
    • Single value access
    • Error handling

Notes​

  • The example supports both in-pod and out-of-pod deployments
  • In-pod deployment uses the pod's service account
  • Out-of-pod deployment requires KubeConfig file
  • ConfigMap changes are automatically reflected
  • Proper RBAC permissions are required
  • Configuration paths can be customized based on needs