Feature Request: Allow openapi references in CRD validation schema

gsoc_proposal.md

Current Work related to validation in CRD

• Validation convention for K8s API's

• How to generate an openAPI-schema

• Kubectl files(pkg/cmd/kubectl)

• Kubernetes Schemas

• swagger.json

Comment

Issues to work upon

• Explain this in open-api/extreactor

• Document pkg/kubectl/cmd/util/openapi

• OpenAPI v3 related improvements

Related Issues

• Generate json-schema from go types

• add support for openapiv3 json output format

• Seeking advice for generating openapi spec for CRD

• Having API doc generated for CRD endpoint

• Need a structured Schema for the JSON

• Solution to $ref

Imp PR

• sample-controller: add example CRD controller

• Sample controller tests

JSON/Open API Schema Reads

• Understanding JSON Schema

• Try JSON website

• What is "$ref" and how does it work?

• JSON Schema $Ref Parser

• Draft-8

• Research Paper - JSONdata model,querylanguages and schema specification

Important Reads

• A Beginner's Guide to Code Generation for REST APIs

• All about Open-API

• Kubernetes API Types

• Code Generation for CustomResources

• This repository implements a simple controller for watching Foo resources as defined with a CustomResourceDefinition (CRD)

• Initial PR OpenAPI support for kubectl

• Learn and Build API

• Story of Aggregated Servers

• K8s supports OpenAPI

• CRD creation read

• Deep-dive API Server - Part1

• Deep-dive API Server - Part2

Problems

• The apiextensions apiserver is not coupled to kube-apiserver right now, then how does apiextensionsapiserver know about the specs of the types of other groups? aggregrator is the only one who knows how to resolve such a reference correctly

• Custom Resource Definitions (CRDs) are not properly deleted under certain conditions here

• Offline work was removed here Remove client side validation in kubectl

Future Works

1. https://github.com/kubernetes/community/blob/master/contributors/design-proposals/api-machinery/aggregated-api-servers.md#future-work

Story of API-EXTENSION-SERVER

• https://github.com/kubernetes/community/blob/master/sig-api-machinery/api-extensions-position-statement.md#q-should-kube-aggregator-be-a-separate-binaryprocess-than-kube-apiserver

About OpenAPI

OpenAPI provides a set of objects, with a specific schema about their naming, order, and contents, that you use to describe each part of your API.