spring cloud implements a front end cross domain problem solution

When we need to provide services from spring boot as an restful interface, if the architecture is separated from the front end, then there is a cross-domain problem. How to solve the cross-domain problem is discussed below.

Solution 1: Add the @CrossOrigin annotation to Controller

The usage is as follows:

@CrossOrigin //  Annotation way  
@RestController 
public class HandlerScanController { 
   
   
  @CrossOrigin(allowCredentials="true", allowedHeaders="*", methods={RequestMethod.GET, 
      RequestMethod.POST, RequestMethod.DELETE, RequestMethod.OPTIONS, 
      RequestMethod.HEAD, RequestMethod.PUT, RequestMethod.PATCH}, origins="*") 
  @PostMapping("/confirm") 
  public Response handler(@RequestBody Request json){ 
     
    return null; 
  } 
} 

Solution 2: Global configuration

The code is as follows:

@Configuration 
  public class MyConfiguration { 
 
    @Bean 
    public WebMvcConfigurer corsConfigurer() { 
      return new WebMvcConfigurerAdapter() { 
        @Override 
        public void addCorsMappings(CorsRegistry registry) { 
          registry.addMapping("/**") 
          .allowCredentials(true) 
          .allowedMethods("GET"); 
        } 
      }; 
    } 
  } 

Solution 3: Use with Filter

Add 1 CorsFilter to the main class of spring boot

/** 
   * 
   * attention: Simple cross domain is GET . HEAD and POST Request, but POST The request of "Content-Type" Can only be application/x-www-form-urlencoded, multipart/form-data  or  text/plain 
   *  Conversely, it is non-simple cross-domain, which has 1 A pre-check mechanism, to put it bluntly, would send two requests, 1 time OPTIONS The request, 1 This is a real request  
   */ 
  @Bean 
  public CorsFilter corsFilter() { 
    final UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource(); 
    final CorsConfiguration config = new CorsConfiguration(); 
    config.setAllowCredentials(true); //  allow cookies Cross domain  
    config.addAllowedOrigin("*");// # Allowed to submit a request to this server URI . * Represents all allowed in SpringMVC If I set theta to zero * Is automatically converted to the current request header Origin 
    config.addAllowedHeader("*");// # Allowed access to the header information ,* All said  
    config.setMaxAge(18000L);//  The cache time of the precheck request (in seconds), during which the same cross-domain request will not be prechecked  
    config.addAllowedMethod("OPTIONS");//  A method that allows you to submit a request, * All allowed  
    config.addAllowedMethod("HEAD"); 
    config.addAllowedMethod("GET");//  allow Get Request method of  
    config.addAllowedMethod("PUT"); 
    config.addAllowedMethod("POST"); 
    config.addAllowedMethod("DELETE"); 
    config.addAllowedMethod("PATCH"); 
    source.registerCorsConfiguration("/**", config); 
    return new CorsFilter(source); 
  } 

Of course, if there are many microservices, you need to add this code to the main class of each service, which violates the DRY principle. It would be better to solve the cross-domain problem in the GATEWAY layer of zuul, once and for all.

For more information about the front cross domain, please refer to: https: / / www ofstack. com article / 83093. htm