I have the following problem:
Request method ‘POST’ not supported

I’m doing it in java “Sprint Boot” and I know that the error is due to the security configuration:
String urlMercadoPago = “/pagomercadopago”;
.antMatchers(urlMercadoPago+”/**”).permitAll()

But the strange thing is that in this case I’m allowing everything, so I shouldn’t have an error.

This is my controller:
@PostMapping(“/pagomercadopago/notificaciones”)

To be more specific, this is my security configuration:

package com.infomarketing.thefrontendforerpsernyc.security;

@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private CustomAuthenticationProvider customAuthenticationProvider;
    @Autowired
    private AutenticadorHomeUsuarios autenticadorHomeUsuarios;

    String urlWebpayExito = "/public/contacto";
    String urlMercadoPago = "/pagomercadopago";


    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf()
        .ignoringRequestMatchers(request -> "XMLHttpRequest".equals(request.getHeader("X-Requested-With")))
        .ignoringAntMatchers(urlWebpayExito)
        .and()
        .authorizeRequests()
        .antMatchers(urlMercadoPago+"/**").permitAll()
        .antMatchers("/").permitAll()
        .anyRequest().authenticated()
        .and()
        .exceptionHandling()
        .accessDeniedPage("/")
        .and()
        .formLogin()
        .loginPage("/sistema")
        .and()
        .logout()
        .logoutUrl("/salir").permitAll()
        .logoutSuccessUrl("/")
        .and()
        .csrf().csrfTokenRepository(csrfTokenRepository());
}



    @Bean
    public CsrfTokenRepository csrfTokenRepository() {
        CookieCsrfTokenRepository repository = CookieCsrfTokenRepository.withHttpOnlyFalse();
        return repository;
    }

    @Bean
    public static PasswordEncoder passwordEncoder(){
        return new BCryptPasswordEncoder();
    }
}

Using the “simulate notification” tool of the payment market integration:
enter image description here

My test code is as follows:

@GetMapping("/pagomercadopago")
    public ModelAndView obtenerTransaccionMercadoPago() throws MPException, MPApiException, ViewRendererException  {
        Authentication auth = SecurityContextHolder.getContext().getAuthentication();
        //Usuarios usuarioLogeado = (Usuarios) auth.getPrincipal();
        ModelAndView mav = new ModelAndView();
        String html = "";
        ConfiguracionMaestra configuracionMaestra = configuracionMaestraService.obtenerConfiguracionMaestraActiva();
        
        //MercadoPagoConfig.setAccessToken(configuracionMaestra.getMercadopagoBearerToken());
        MercadoPagoConfig.setAccessToken(mercadopagoAccessToken);
        PreferenceItemRequest itemRequest =
               PreferenceItemRequest.builder()
                   .id("1234")
                   .title("Revisar los avances de la denuncia")
                   .description("Avances de la denuncia que tienes en curso.")
                   .categoryId("denuncia")
                   .quantity(1)
                   .currencyId("CLP")
                   .unitPrice(new BigDecimal("100"))
                   .build();
        List<PreferenceItemRequest> items = new ArrayList<>();
        items.add(itemRequest);
        
        PreferenceBackUrlsRequest backUrls =
                   PreferenceBackUrlsRequest.builder()
                   //los dominios no puede ser locales
                       .success(dominioUrl+"/pagomercadopago/exito")
                       .pending(dominioUrl+"/pagomercadopago/fail")
                       .failure(dominioUrl+"/pagomercadopago/pendiente")
                       .build();

        PreferenceRequest request = PreferenceRequest.builder()
                .items(items)
                .backUrls(backUrls)
                //.notificationUrl("https://techkeeper.cl/pagomercadopago/notificaciones")
                .build();
        
        PreferenceClient client = new PreferenceClient();
        Preference preference = client.create(request);
        
        //mav.addObject("mercadoPagoPublicKey", configuracionMaestra.getMercadopagoPublicoClientId());
        mav.addObject("mercadoPagoPublicKey", mercadopagoPublicKey);
        //mav.addObject("usuario", usuarioLogeado);
        mav.addObject("idPreference", preference.getId());
        html=vistasService.cargarVistas("HEAD-PUBLICO");
        html+=vistasService.cargarVistas("NAVBAR-PUBLICO");
        html+=vistasService.cargarVistas("VISTA-PAGO-MERCADOPAGO");
        html+=vistasService.cargarVistas("FOOTER-PUBLICO");
        mav.setViewName(html);
        return mav;
    }

Notification Post Settings:

    @PostMapping("/pagomercadopago/notificaciones")
    public String notificacionesPagoMercadoPago(
            @RequestHeader("x-signature") String signatureHeader,
            @RequestParam(name="topic", required=false) String topic ,
            @RequestParam(name="id" , required=false) String idMerchantOrder,
            @RequestParam(name="type" , required=false) String type,
            @RequestParam(name="data.id" , required=false) String idPayment) throws IOException, ViewRendererException {
        System.out.println("notificaciones mercadopago");
        System.out.println(signatureHeader);
        String[] parts = signatureHeader.split(",");
        String ts = null;
        String v1 = null;

        for (String part : parts) {
            if (part.startsWith("ts=")) {
                ts = part.substring(3);
            } else if (part.startsWith("v1=")) {
                v1 = part.substring(3);
            }
        }
        
        // Template original 
        String template = "id:[data.id_url];ts:[ts_header];";
        template = template.replace("[data.id_url]", idPayment).replace("[ts_header]", ts);

        String cyphedSignature = new HmacUtils("HmacSHA256", "34c22c74aaf0ebb7ffd1fce3c8b0a5e33d6063827976ce59f10f500bb371f393").hmacHex(template);
        System.out.println("cyphedSignature: "+cyphedSignature);
        System.out.println("v1: "+v1);
        
        //Usuarios usuario = generalController.obtenerUsuarioLogeado();
        mercadoPagoService.completaPagoMercadoPago(topic, idMerchantOrder, type, idPayment, usuario.getIdUsuario());
        return "OK";
    }