Access-Control-Allow-Origin is missing - spring

Question

I am using the Spring 4 as backend for my angular Application.When the angular app makes a request to the spring app then I am getting an error
Access to **XMLHttpRequest at 'http://localhost:8080/AdminController/allAdmins' from origin 'http://localhost:4200' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.**
I am using custom filter to validate each user request
Code for my Filter is:
#Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest httpReq = (HttpServletRequest) request;
HttpServletResponse httpResp = (HttpServletResponse) response;
// Ignoring the request URLs
if (Utils.ignoreURLs(IGNORE_URLS, httpReq.getRequestURI()) == true) {
filterChain.doFilter(request, response);
return;
}
// Fetching all the header params from request
HttpServletRequest httpRequest = (HttpServletRequest) httpReq;
Enumeration<String> headerNames = httpRequest.getHeaderNames();
String loggedUserId = null;
String authToken = null;
if (headerNames != null) {
while (headerNames.nextElement() != null && headerNames.hasMoreElements()) {
loggedUserId = httpRequest.getHeader(Constants.LOGGED_USER_ID);
authToken = httpRequest.getHeader(Constants.AUTH_TOKEN);
}
}
if (Utils.isBlank(loggedUserId) == true || Utils.isBlank(authToken) == true) {
httpResp.setContentType(MediaType.APPLICATION_JSON_VALUE);
mapper.writeValue(httpResp.getWriter(), getErrorDetailsMap());
return;
}
ApplicationContext appContext = AppContextConfig.getApplicationContext();
AccessManager accessManager = (AccessManager) appContext.getBean(AccessManager.class);
// I am validating authentication token here
if(accessManager.isValidToken(loggedUserId, authToken) == false) {
httpResp.setContentType(MediaType.APPLICATION_JSON_VALUE);
mapper.writeValue(httpResp.getWriter(), getErrorDetailsMap());
return;
}
filterChain.doFilter(request, response);
}

Answer 1

Just use a #CrossOrigin annotation over the controllers and define this bean in your SecurityConfig:
#Bean
public CorsConfigurationSource corsConfigurationSource() {
final CorsConfiguration configuration = new CorsConfiguration();
configuration.setAllowedOrigins(Arrays.asList("http://localhost:4200"));
configuration.setAllowedMethods(Arrays.asList("GET", "POST", "OPTIONS"));
configuration.setAllowCredentials(true);
configuration.setAllowedHeaders(Arrays.asList("*"));
configuration.setExposedHeaders(Arrays.asList("x-auth-token", "xsrf-token"));
final UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
source.registerCorsConfiguration("/**", configuration);
return source;
}
edit
Or maybe the problem is missing headers, in which the following filter should be sufficient.
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
#Component
public class SimpleCORSFilter implements Filter {
private final Logger log = LoggerFactory.getLogger(SimpleCORSFilter.class);
public SimpleCORSFilter() {
log.info("SimpleCORSFilter init");
}
#Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", request.getHeader("Origin"));
response.setHeader("Access-Control-Allow-Credentials", "true");
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With, remember-me");
chain.doFilter(req, res);
}
#Override
public void init(FilterConfig filterConfig) {
}
#Override
public void destroy() {
}
}