Open api code generator

An opinionated code geneartor for API driven development

Featues Supported

• Languages Supported
  • Node.js
  • Golang
• Project Initialization
• Service Generation
  • Required Validation generation
  • Custom error generation
  • Test generation with storage mock
• Adapter Generation
  • Http Generation
  • Storage Generation[Some 🐞 🐞]

Usage

code-gen [path-to-api-spec] [language] [command] [serviceName(optional)]

Commands list

• init: Initializes project/adds new updates
• services: generate services
• http: generates http layer
• storage: generates storage layer

Notes

• Please run npm i after running init command
• Passing optional serviceName generates only for that service
• Sevice name should match specs.tag[0] in api spec file

How to Start

Generate Project

code-gen [path-to-api-spec] [language] init

• This step generates a bare project with server, loggers, config and request helpers.
• The server file can be changed, if custom server implementation is needed

Generate Services

code-gen [path-to-api-spec] [language] services

• Things to know:

  • The service functions are grouped according to first tag in tags in spec file

  • Service/handler Operations(like creteUser) will be generated using OperationId, so it is must in api spec

  • types file will be over-written when running commands in future.

  • Custom Validations should be kept in the service operation file and not in types

  • Custom errors will be generated if there is errors in api spec components

  • Custom error codes will be generated if there is errCodes in api spec components

  components:
    errors:
      - name: ValidationError
        httpStatusCode: 400
    errCodes:
      - name: ValueRequired
        code: "_value_required"
  

  • For automatic required validations use required feature of openapi spec

  components:
    schemas:
      CreateUserPayload:
        type: object
        required:
        - name
        - gender
        - birthday
        properties:
          name: 
            type: string
          gender:
            type: string
          birthday:
            type: string
  

Generate Http Adapters

code-gen [path-to-api-spec] [language] http

• Things to know:
  • The handlers are grouped according to first tag in tags in spec file
  • routes file will be over-written when running commands in future.

Generate Storage Adapters

code-gen [path-to-api-spec] [language] storage

• This step generates storage, default mongo, adapter
• Things to know:
  • The storage are grouped according to first tag in tags in spec file
  • At least one component/schema with entity name is must for generating the storage

  components:
    schemas:
      User:
      type: object
      properties:
          name: 
          type: string
  

Generated Project structure

tree
|-- src // contains all the source code
|   |-- services // conatins all the services
|   |   |-- [servicename] // service directory for the domain
|   |   |   |   |-- adapters // adapters for the service
|   |   |   |   |   |-- api // all the api adapters
|   |   |   |   |   |   |-- http
|   |   |   |   |   |   |-- async
|   |   |   |   |   |-- storage // all the storage adapters
|   |   |   |   |   |   |-- mongo
|   |   |   |   |   |   |-- postgresql // not implemented
|   |-- lib // contains all the utilities and libraries
|   |   |-- context // creates context for request cycle
|   |   |-- errors // custom error implementations and codes
|   |   |-- middlewares // request middlewares
|   |   |   |-- logRequest
|   |   |   |-- requestId
|   |   |-- test // test helpers
|   |   |-- db // db helpers and connectors
|   |   |-- logger
|   |-- config
|-- [indexFile] // contains server and init code
|-- [packageManagerFile]
|-- Readme.md
|-- .gitignore