weseek__growi/apps/app/bin/openapi/generate-operation-ids/generate-operation-ids.ts

import SwaggerParser from '@apidevtools/swagger-parser';
import type { OpenAPI3, OperationObject, PathItemObject } from 'openapi-typescript';

const toPascal = (s: string): string => s.split('-').map(w => w[0]?.toUpperCase() + w.slice(1)).join('');

const createParamSuffix = (params: string[]): string => {
  return params.length > 0
    ? params.reverse().map(param => `By${toPascal(param.slice(1, -1))}`).join('')
    : '';
};


/**
 * Generates a PascalCase operation name based on the HTTP method and path.
 *
 * e.g.
 * - `GET /foo` -> `getFoo`
 * - `POST /bar` -> `postBar`
 * - `Get /foo/bar` -> `getBarForFoo`
 * - `GET /foo/{id}` -> `getFooById`
 * - `GET /foo/{id}/bar` -> `getBarByIdForFoo`
 * - `GET /foo/{id}/{page}/bar` -> `getBarByPageByIdForFoo`
 *
 */
function createOperationId(method: string, path: string): string {
  const segments = path.split('/').filter(Boolean);
  const params = segments.filter(s => s.startsWith('{'));
  const paths = segments.filter(s => !s.startsWith('{'));

  const paramSuffix = createParamSuffix(params);

  if (paths.length <= 1) {
    return `${method.toLowerCase()}${toPascal(paths[0] || 'root')}${paramSuffix}`;
  }

  const [resource, ...context] = paths.reverse();
  return `${method.toLowerCase()}${toPascal(resource)}${paramSuffix}For${context.reverse().map(toPascal).join('')}`;
}

export async function generateOperationIds(inputFile: string, opts?: { overwriteExisting: boolean }): Promise<string> {
  const api = await SwaggerParser.parse(inputFile) as OpenAPI3;

  Object.entries(api.paths || {}).forEach(([path, pathItem]) => {
    const item = pathItem as PathItemObject;
    (['get', 'post', 'put', 'delete', 'patch', 'options', 'head', 'trace'] as const)
      .forEach((method) => {
        const operation = item[method] as OperationObject | undefined;
        if (operation == null || (operation.operationId != null && !opts?.overwriteExisting)) {
          return;
        }
        operation.operationId = createOperationId(method, path);
      });
  });

  const output = JSON.stringify(api, null, 2);

  if (output == null) {
    throw new Error(`Failed to generate operation IDs for ${inputFile}`);
  }

  return output;
}