需求：需要再請求頭里面添加‘id_token" 自定義字段。
問題描述：后端已經設置了跨域請求，很奇怪明明后端設置了允許跨域，為什么添加了headers，在里面寫id_token就不行，原因是因為后端沒有設置請求頭里有這個字段。也就是說后端要設置了允許有這個字段，前端才可以發送，否則瀏覽器會有一個options預監測請求，發現了后端沒設置這個字段，就直接攔截了。
解決：需要后端設置setHeader那里添加這個自定義字段。 （或者為 * 也可以，猜測，這個沒實踐）
代碼配置更改如下：
原先后端配置：
@Override
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
req.setAttribute("org.apache.catalina.ASYNC_SUPPORTED", true);
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", ((HttpServletRequest) req).getHeader("Origin"));
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "Content-Disposition,Origin, X-Requested-With, Content-Type, Accept,Authorization");
response.setHeader("Access-Control-Allow-Credentials","true"); //是否支持cookie跨域
chain.doFilter(req, res);
}
更改后的后端配置：
@Override
public void doFilter(ServletRequest req, ServletResponse res,
FilterChain chain) throws IOException, ServletException {
req.setAttribute("org.apache.catalina.ASYNC_SUPPORTED", true);
HttpServletResponse response = (HttpServletResponse) res;
response.setHeader("Access-Control-Allow-Origin", ((HttpServletRequest) req).getHeader("Origin"));
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "Content-Disposition,Origin, X-Requested-With, Content-Type, Accept,Authorization,id_token");
response.setHeader("Access-Control-Allow-Credentials","true"); //是否支持cookie跨域
chain.doFilter(req, res);
}