Update type definitions and implementation to support multiple responses

[leorossi]

To check it

• Create a new platformatic service with create-platformatic
• Add a route like this

  fastify.get('/redirect', {
    schema: {
      response: {
        302: {
          type: 'object',
          properties: {}
        },
        400: {
          type: 'object',
          properties: {
            message: { type: 'string' }
          }
        }
      }
    }
  }, 
    async (request, reply) => {
    return reply.code(302).redirect('https://google.com')
  })

• Start the application with npm start
• Generate frontend boilerplate files with platformatic frontend http://127.0.0.1:3042 ts
  File api-types.d.ts would include this code

interface FullResponse<T> {
  'statusCode': number;
  'headers': object;
  'body': T;
}
...
interface GetRedirectRequest {
}

interface GetRedirectResponseFound {
}

interface GetRedirectResponseBadRequest {
  'message': string;
}

export interface Api {
  setBaseUrl(newUrl: string) : void;
  getRedirect(req: GetRedirectRequest): Promise<FullResponse<GetRedirectResponseFound> | FullResponse<GetRedirectResponseBadRequest>>;
}

The implementation file api.ts would include this snippet

export const getRedirect: Api['getRedirect'] = async (request) => {
  const response = await fetch(`${baseUrl}/redirect?${new URLSearchParams(Object.entries(request || {})).toString()}`)

  let body = await response.text()

  try {
    body = JSON.parse(await response.json())
  }
  catch (err) {
    // do nothing and keep original body
  }

  return {
    statusCode: response.status,
    headers: response.headers,
    body
  }
}

[mcollina]

Could you add a test?

[mcollina]

lgtm