Kubernetes API
A Kubernetes API is an API that allows users and components to communicate and manage Kubernetes clusters.
- Context:
- It is the primary interface used to manage, query, and manipulate the state of objects and components in a Kubernetes cluster.
- It is fundamental to the control plane of Kubernetes and is central to all communication within the system.
- It can (typically) facilitate operations on Kubernetes resources like Pods, ConfigMaps, Services, and Namespaces via REST API calls.
- It can (often) be accessed through command-line tools like kubectl, which internally translates user commands into API requests, or directly through REST calls.
- It can be organized into two main specifications: the Discovery API and the OpenAPI document. The Discovery API lists available resources, while OpenAPI provides comprehensive schema and documentation.
- It supports various HTTP verbs such as GET, POST, PUT, PATCH, and DELETE to create, modify, and retrieve resources within the cluster.
- It can enable multiple API versions and groups concurrently, allowing gradual and smooth evolution of API features.
- ...
- Example(s):
- Kubernetes API v1.18.
- Using kubectl commands to query resource details like
kubectl get nodesor modify resource configurations likekubectl apply -f <filename.yaml>. - Leveraging the API for automated cluster management through client libraries to write applications or scripts that manipulate cluster state.
- Kubernetes API Pod Management,
- Kubernetes API Service Discovery,
- ...
- Counter-Example(s):
- See: Kubernetes Resource Object, Kubernetes Control Plane, Container Orchestration System, Cluster Management System, API Gateway, kubectl, REST API.
References
2024
- (ChatGPT-OpenAI, 2024) ⇒ Prompt: Summarize the concept Kubernetes API in 1- 2 paragraphs. ChatGPT (model:gpt-4-turbo-preview). Retrieved: 2024-05-05.
- QUOTE: The Kubernetes API is a foundational element of the Kubernetes container orchestration platform, serving as the interface through which users, cluster services, and external components communicate and manage the cluster's lifecycle and operations. It is structured around REST principles, allowing for operations like creating, reading, updating, and deleting (often abbreviated as CRUD) Kubernetes resources such as pods, services, and deployments. These resources and their state are stored in the Kubernetes cluster's etcd database, making the API the gatekeeper to this centralized source of truth.
Through the Kubernetes API, users can interact with the cluster using various tools, including the command-line interface (CLI) tool kubectl, Kubernetes client libraries available in multiple programming languages, or direct HTTP requests. The API serves as an abstraction layer that decouples operations and management from the underlying infrastructure, facilitating a consistent and extensible framework for deployment, scaling, and management of containerized applications. Moreover, the API's extensibility supports custom resources and controllers, enabling users to extend Kubernetes in a declarative manner for custom usage scenarios. This extensibility is key to Kubernetes' adaptability and widespread adoption, allowing it to serve as a robust platform for complex, highly available, and scalable applications.
- QUOTE: The Kubernetes API is a foundational element of the Kubernetes container orchestration platform, serving as the interface through which users, cluster services, and external components communicate and manage the cluster's lifecycle and operations. It is structured around REST principles, allowing for operations like creating, reading, updating, and deleting (often abbreviated as CRUD) Kubernetes resources such as pods, services, and deployments. These resources and their state are stored in the Kubernetes cluster's etcd database, making the API the gatekeeper to this centralized source of truth.
2020a
- (Kubernetes.io, 2020) ⇒ https://kubernetes.io/docs/concepts/overview/kubernetes-api/
- QUOTE: ... The Kubernetes API lets you query and manipulate the state of objects in Kubernetes. The core of Kubernetes' control plane is the API server and the HTTP API that it exposes. Users, the different parts of your cluster, and external components all communicate with one another through the API server.
The core of Kubernetes' control plane is the API server . The API server exposes an HTTP API that lets end users, different parts of your cluster, and external components communicate with one another.
The Kubernetes API lets you query and manipulate the state of objects in the Kubernetes API (for example: Pods, Namespaces, ConfigMaps, and Events).
API endpoints, resource types and samples are described in the API Reference.
- QUOTE: ... The Kubernetes API lets you query and manipulate the state of objects in Kubernetes. The core of Kubernetes' control plane is the API server and the HTTP API that it exposes. Users, the different parts of your cluster, and external components all communicate with one another through the API server.
2020b
- (Kubernetes.io, 2020) ⇒ https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.18/
- QUOTE: ... You can use the Kubernetes API to read and write Kubernetes resource objects via a Kubernetes API endpoint. …