How to ensure that the generated JSON does not return error to the Customer?

Question

I created a Web API that returns a JSON and who is having a problem similar to the question JSONP: status code 200 OK and still returns $.Ajax(... error:Function()...). Client consumes the API with Nodes like this:

refresh() {
        axios
            .get(`${URL}"${this.generateDate()}"`)

            .then(resp => {
                console.log(resp);
                this.setState({ ...this.state, services: resp.data, loading: false });

                let statusModal = swal.getState();

                //if (!statusModal.isOpen) {
                //  swal.close();
                //}
            })
            .catch(e => {
                console.log('O erro é =>', e);
                //swal('Ocorreu algum problema!', 'Entre em contato com o responsável', 'error');
                //this.setState({ ...this.state, loading: false });
            });
    }

The return of JSON is 200, but in the console displays the error described below
I memorized the API method with the Cors to obtain the conpatibility of origins, however the error persists.

My question is:

Just this snippet of code where I memorize the api method is enough ?

This is the API method: improved at the suggestion of Danilo Ribeiro da Silva

    [EnableCors(origins: "*", headers: "*", methods: "*", exposedHeaders: "*")]
    [RoutePrefix("api/monitora")]
    public class MonitoraController : ApiController
    {

        // GET: api/Painel/5
        [Route("GetPainel")]
        public IHttpActionResult GetPainel(string dtHoraExecuta)
        {
            try
            {
                DateTime dt = DateTime.MinValue;
                if (!DateTime.TryParse(dtHoraExecuta.Replace("\"", ""), out dt))
                    return StatusCode(HttpStatusCode.NotAcceptable); // 406


                List<ProductType> lreturn = new List<ProductType>();
                PainelMonitoracaoBusiness obj = new PainelMonitoracaoBusiness();
                dt = Convert.ToDateTime(Convert.ToDateTime(dtHoraExecuta.Replace("\"", "")));

                var _painel = obj.ObterDadosPainel(dt);

                if (_painel == null)
                {
                    var resp = new HttpResponseMessage(HttpStatusCode.NotFound)
                    {
                        Content = new StringContent(string.Format("Não foram encontrado dados para esse período. = {0}", dtHoraExecuta)),
                        ReasonPhrase = "Serviços não encontrados."
                    };
                    throw new HttpResponseException(resp);
                }

                for (int i = 0; i < _painel.Count; i++)
                {

                    ProductType prd = new ProductType();

                    for (int z = 0; z < _painel[i].lservices.Count; z++)
                    {
                        if (_painel[i].ID_SERVICO == _painel[i].lservices[z].ID_SERVICO)
                        {
                            prd.productType = _painel[i].productType;
                            SubServico subServico = new SubServico();
                            subServico.statusAll = _painel[i].lservices[z].statusAll;
                            subServico.subtype = _painel[i].lservices[z].subtype;

                            Info infoAbertura = new Info();
                            infoAbertura.mount = _painel[z].lservices[0].info[0].mount;
                            infoAbertura.status = _painel[z].lservices[0].info[0].status;
                            infoAbertura.type = _painel[z].lservices[0].info[0].type;

                            Info infoFechamento = new Info();
                            infoFechamento.mount = _painel[z].lservices[0].info[1].mount;
                            infoFechamento.status = _painel[z].lservices[0].info[1].status;
                            infoFechamento.type = _painel[z].lservices[0].info[1].type;

                            subServico.info.Add(infoAbertura);
                            subServico.info.Add(infoFechamento);

                            prd.services.Add(subServico);
                        }                        
                    }
                    lreturn.Add(prd);
                }

                return Ok(lreturn);
            }
            catch (Exception)
            {
                return StatusCode(HttpStatusCode.ExpectationFailed); // 417
            }
        }

This is the error I captured in the browser:

 erro é => TypeError: Cannot read property 'value' of undefined

Error image:

Answer 1

You can handle errors according to the Response status code as you did when you did not find the panel.

What I recommend is to always validate user data entries. In the case of your Convert.ToDateTime exchange for DateTime.TryParse that you can make this validation simple.

I always put a block of Try catch with a return that does not show error to the user.

See that the same action has multiple status returns:

• 406 Not Acceptable - When user data entry is invalid
• 404 Not Found - When not to find the panel
• 417 Expectation Failed - When some internal error occurs
• 200 OK - When successful

Example below:

public IHttpActionResult GetPainel(string dtHoraExecuta)
{
    try
    {
        // Verifica se os dados passados pelo cliente são válidos
        if (!ModelState.IsValid)
            return StatusCode(HttpStatusCode.NotAcceptable); // 406

        // Verifica se os dados passados pelo cliente são válidos
        DateTime dt = DateTime.MinValue;
        if(!DateTime.TryParse(dtHoraExecuta.Replace("\"", ""), out dt))
            return StatusCode(HttpStatusCode.NotAcceptable); // 406

        // Obtem os dados...
        if (dados == null)
            return NotFound();

        //...

        return Ok(dados)
    }
    catch (Exception)
    {
        // Erro interno do servidor
        return StatusCode(HttpStatusCode.ExpectationFailed); // 417
    }
}