Resource Management

The client-go library offers a comprehensive set of tools for managing Kubernetes resources, simplifying the process of deploying, managing, and monitoring applications within a Kubernetes cluster.

Core Features:

• Resource Management: Efficiently manage Kubernetes resources such as Pods, Deployments, Services, and custom resources. This enables seamless application lifecycle management. examples/create-update-delete-deployment/README.md examples/dynamic-create-update-delete-deployment/README.md
• Informer Framework: Enables efficient and scalable resource monitoring by providing a mechanism to watch for changes in the Kubernetes API server. examples/README.md examples/workqueue/README.md
• Work Queues: Provides a rate-limited work queue to prevent controllers from becoming overwhelmed by frequent updates. examples/README.md examples/workqueue/README.md
• Leader Election: Implements a robust leader election mechanism for ensuring high availability (HA) in controllers. This guarantees that only a single instance of a controller is active at any given time. examples/leader-election/README.md
• Dynamic Client: Offers a flexible approach to interact with the Kubernetes API by allowing interactions with any resource without needing to know the specific resource type beforehand. examples/dynamic-create-update-delete-deployment/README.md

Common Scenarios:

• Deploying Applications: Use client-go to create and manage Kubernetes resources for deploying and managing applications. examples/create-update-delete-deployment/README.md examples/dynamic-create-update-delete-deployment/README.md
• Building Controllers: Build robust and scalable controllers to manage the state of your Kubernetes cluster. This can involve handling resource creation, updates, and deletion based on custom rules. examples/workqueue/README.md
• Custom Resource Definitions (CRDs): Leverage client-go to interact with custom resources, extending the Kubernetes API to suit specific application needs. examples/README.md
• Ensuring High Availability: Implement highly available controllers by utilizing the leader election functionality. This guarantees that a single leader will always be managing a particular resource or set of resources, even during failures. examples/leader-election/README.md

Example Usage:

• Out-of-Cluster Client Configuration: Connect to a Kubernetes cluster from outside the cluster using a kubeconfig file. examples/out-of-cluster-client-configuration/README.md
• In-Cluster Client Configuration: Access the Kubernetes API from within a Pod deployed in the cluster. examples/in-cluster-client-configuration/README.md

Key Concepts:

• Declarative Configuration: Client-go provides a declarative approach for defining resource configurations, allowing for clear and concise resource creation and updates. applyconfigurations/core/v1/resourcestatus.go applyconfigurations/autoscaling/v2beta1/resourcemetricsource.go applyconfigurations/autoscaling/v2beta1/resourcemetricstatus.go applyconfigurations/core/v1/resourcerequirements.go applyconfigurations/resource/v1alpha3/resourcepool.go applyconfigurations/core/v1/containerstatus.go applyconfigurations/autoscaling/v2/resourcemetricstatus.go applyconfigurations/autoscaling/v2/resourcemetricsource.go applyconfigurations/resource/v1alpha3/resourceclaimstatus.go applyconfigurations/autoscaling/v2beta2/resourcemetricsource.go applyconfigurations/autoscaling/v2beta2/resourcemetricstatus.go
• Resource Locks: Securely manage resource access and prevent race conditions during leader election. tools/leaderelection/resourcelock/interface.go

Further Information:

• Documentation: Refer to the client-go documentation for comprehensive information about its features and usage. README.md
• Contribution: Contribute to the client-go project by submitting pull requests to the Kubernetes repository. README.md

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.

gentype/ - This directory contains generated Go types for the Kubernetes API.

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.

rest/ - This directory contains code for working with the REST API in 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.