OpenAPI code generator for Google Apps Script

A CLI tool that generate codes for Google Apps Script.

An example project is here.

Roadmap

• [x] .yml file support
• [x] typescript code generation
• [ ] requestBody parsing(support type: array, type: object in object)
• [ ] $ref and $component parsing
• [ ] nested responses parsing(support type: array in object)
• [ ] server and example field support
  • if google.script.run is not defined, api calls to localhost
• [ ] .json file support
• [ ] javascript(jsdoc) code generation
• [ ] throw error for invalid input(a file specified by --spec option)
• [ ] http status 400 support(rejectable)

not supported

• API spec bundle
  • Use a dedicated tool like Redocly CLI

Usage

npm install -D openapi-generator-gas
npx openapi-generator-gas --spec openapi.yml --outfile ./frontend/src/openapi.ts --frontend # Generate codes for frontend
npx openapi-generator-gas --spec openapi.yml --outfile ./backend/src/openapi.ts --backend # Generate codes for backend

Example

• openapi.yml

openapi: 3.0.3
info:
  title: My OpenAPI spec
  summary: example spec
  version: 0.0.1
servers:
  - url: http://localhost:8080
    description: A local server

paths:
  /todo:
    get:
      summary: get TODO item                 # anything ok(not used)
      description: get TODO item             # anything ok(not used)
      operationId: getTodoItem
      parameters:
        - name: itemId
          in: query                          # anything ok(not used)
          required: true
          schema:
            type: integer
      responses:
        200:                                 # 200 only supported(will be function's return type)
          description: specific TODO item    # anything ok(not used)
          content:
            application/json:                # `application/json` only supported
              schema:
                type: object
                required:
                  - itemId
                  - title
                properties:
                  itemId:
                    type: integer
                  title:
                    type: string
                  description:
                    type: string

• generated codes for frontend

export type GetTodoItemRequest = {
  itemId: number;
}

export type GetTodoItemResponse = {
  itemId: number;
  title: string;
  description?: string;
}

export function getTodoItem(request: GetTodoItemRequest): Promise<GetTodoItemResponse> {
  return new Promise((resolve, reject) => {
    google.script.run
      .withSuccessHandler(resolve)
      .withFailureHandler(reject)
      .getTodoItem(request);
  });
}

and codes that you implemented

import { getTodoItem } from 'path/to/outfile.ts';

const test = async () => {
  const req = { itemId: 1 };
  const res = await getTodoItem(req);
};

• generated codes for backend

export type GetTodoItemRequest = {
  itemId: number;
}

export type GetTodoItemResponse = {
  itemId: number;
  title: string;
  description?: string;
}

export type IGetTodoItem = (request: GetTodoItemRequest) => GetTodoItemResponse;

and codes that you implemented

import type { IGetTodoItem } from 'path/to/outfile.ts';

const getTodoItem: IGetTodoItem = (req) => {
  const itemId = req.itemId;

  return {
    itemId: 1,
    title: 'Some title',
    description: 'Some description',
  }
}