Requests blocked by CORS policy in spring boot and angular

在本地啓動Spring Boot後端和Angular前端調試時遇到跨域訪問的問題致使前端請求失敗。

錯誤描述

Access to XMLHttpRequest at 'http://localhost:8080/...' from origin 'http://localhost:4201' 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.

解決方案

添加一個Filter使後端支持跨域訪問，Spring Boot會自動掃描Filter，無需手動添加。

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, PUT, 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() {
    }

}

參考：https://stackoverflow.com/questions/32319396/cors-with-spring-boot-and-angularjs-not-working

轉載請註明出處：http://www.javashuo.com/article/p-vhqfbhog-md.html