kubernetes / client-go

CI/CD Integration for client-go

Implementing continuous integration and continuous delivery (CI/CD) pipelines with client-go is essential for automated application deployment and updates. The client-go library provides various features and tools to facilitate CI/CD integration, including:

1. Dynamic Client:

  • The dynamic package in client-go allows for interacting with Kubernetes resources using their API schema.
  • This enables flexibility in working with different resource types without needing to explicitly define them in code.
  • Example: The examples/dynamic-create-update-delete-deployment/README.md file provides a comprehensive illustration of using the dynamic package to perform CRUD operations on Deployment resources.

2. Fake Client:

  • client-go provides a fake client for testing purposes.
  • This fake client simulates interactions with the Kubernetes API server, enabling testing of logic without requiring a real cluster.
  • Example: The examples/fake-client/README.md file demonstrates the use of a fake client in conjunction with the SharedInformerFactory to test code that relies on events from Kubernetes resources.

3. Informers:

  • Informers provide a mechanism for efficiently watching Kubernetes resources and receiving updates when they change.
  • They cache resource data locally, reducing the need to constantly query the API server.
  • Example: The examples/create-update-delete-deployment/README.md file shows an example of utilizing the informer framework to manage Deployments.

4. Work Queues:

  • client-go provides work queues for handling asynchronous processing of events from informers.
  • This ensures that the processing of events does not block other operations and allows for efficient resource management.
  • Example: The examples/README.md file demonstrates how to use work queues and informers to create a hotloop-free controller.

5. Leader Election:

  • client-go includes a leader election package to enable the implementation of high-availability controllers.
  • This ensures that only one instance of a controller is running at a time, even in distributed environments.
  • Example: The examples/README.md file showcases the use of the leader election package to implement HA controllers.

Examples:

The following examples demonstrate how to use client-go for CI/CD integration:

Code Snippets:

The following code snippets illustrate the use of client-go for CI/CD integration:

Top-Level Directory Explanations

applyconfigurations/ - This directory contains examples and tests for applying Kubernetes configurations using the client-go library.

discovery/ - This directory contains code related to service discovery in Kubernetes.

dynamic/ - This directory contains code for working with dynamic resources in the Kubernetes API.

examples/ - This directory contains example usage of the client-go library.

informers/ - This directory contains code for caching Kubernetes resources using informers.

kubernetes/ - This directory contains the main package for the client-go library, which provides types and functions for interacting with the Kubernetes API.

listers/ - This directory contains interfaces and implementations for listing Kubernetes resources.

metadata/ - This directory contains code related to metadata in Kubernetes.

openapi/ - This directory contains OpenAPI definitions for the Kubernetes API.

pkg/ - This directory contains compiled Go packages for the client-go library.

plugin/ - This directory contains code for loading plugins for the client-go library.

scale/ - This directory contains code for working with scale and autoscaling in Kubernetes.

tools/ - This directory contains various tools for working with the client-go library.

util/ - This directory contains utility functions for the client-go library.