Swagger OpenAPI Specification - Describing RESTful APIs(using JSON)

OpenAPI Specification(formerly Swagger Specification) defines a standard, language-agnostic interface to RESTful APIs which allows both humans and computers to discover and understand the capabilities of the service without access to source code, documentation, or through network traffic inspection. An OpenAPI definition can then be used by documentation generation tools to display the API, code generation tools to generate servers and clients in various programming languages, testing tools, and many other use cases.

API specifications can be written in YAML or JSON. The format is easy to learn and readable to both humans and machines.

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (both 2.0 and 3.0 are supported).

The core of OpenAPI Generator is based on Mustache Templates. Every line of code in your generated SDK is created by reading a template file in and substituting values into it based on your OpenAPI descriptions.

ref:

OpenAPI specification(swagger) - https://swagger.io/specification/

github OpenAPI Specification - https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md

Generate Swgager API HTML online from YAML - https://editor.swagger.io/

Generate Swgager API JSON online from YAML(from File menu) - https://editor.swagger.io/

 

OpenAPI V3 code generation -  

    1.  https://mux.com/blog/an-adventure-in-openapi-v3-api-code-generation/

    2. https://swagger.io/tools/swagger-codegen

Usage of openapi-generator-cli - https://github.com/OpenAPITools/openapi-generator

Use mustache templates with Openapi generator code - https://openapi-generator.tech/docs/templating/ 

Openapi generator source code - https://github.com/OpenAPITools/openapi-generator/tree/master/modules/openapi-generator/src/main

swagger openapi generator mustache resource templates - https://github.com/swagger-api/swagger-codegen/tree/master/modules/swagger-codegen/src/main/resources

swagger openapi generator mustache templates for golang client -
https://github.com/swagger-api/swagger-codegen/tree/master/modules/swagger-codegen/src/main/resources/go

swagger openapi generator mustache templates golang server - https://github.com/swagger-api/swagger-codegen/tree/master/modules/swagger-codegen/src/main/resources/go-server
 

openapi Custom code generator & template - https://openapi-generator.tech/docs/customization/  

Misc =>

     1. https://www.openapis.org/

     2. https://swagger.io/docs/specification/about/