在Heroku上的Java JAX-RS API上启用CORS请求

Question

我有一个Java Web应用程序，我从jQuery向使用JAX-RS配置的Rest API发送一些请求，在我的本地计算机上它运行正常，但在Heroku上部署之后，它给了我一个错误

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at...

特别是，我正在从jQuery向此端点发送POST请求。

我已经为我的应用程序配置了CORS过滤器，这导致它在我的本地计算机上运行（在此之前，应用程序在我的本地计算机上给了我相同的错误）。无论如何，这是我如何配置它

@Provider
public class CORSFilter implements ContainerResponseFilter {

@Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext) {
    responseContext.getHeaders().add("Access-Control-Allow-Origin", "*");
    responseContext.getHeaders().add("Access-Control-Allow-Headers",
            "Location, origin, content-type, accept, authorization, enctype, content-disposition");
    responseContext.getHeaders().add("Access-Control-Expose-Headers", "Location");
    responseContext.getHeaders().add("Access-Control-Allow-Methods",
            "GET, POST, PUT, DELETE, OPTIONS, HEAD");
}

}

我还尝试将这些标头添加到我回馈的Response对象作为对请求的响应，但没有运气。

我相信它必须是一些Heroku的东西，但我不确定。

任何帮助，将不胜感激。

Answer 1

使用普通过滤器：

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.HttpServletResponse;

public class CORSFilter implements Filter {

  private static final String ACCESS_CONTROL_ALLOW_ORIGIN = "Access-Control-Allow-Origin";
  private static final String ACCESS_CONTROL_ALLOW_METHODS = "Access-Control-Allow-Methods";
  private static final String ACCESS_CONTROL_ALLOW_HEADERS = "Access-Control-Allow-Headers";
  private static final String ACCESS_CONTROL_EXPOSE_HEADERS = "Access-Control-Expose-Headers";
  private static final String ALL = "*";
  private static final String ALLOWED_METHODS = "GET";
  private static final String ALLOWED_HEADERS =
      "origin, content-type, accept, Authorization, x-requested-with";
  private static final String EXPOSE_HEADERS = "TEST";

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
      throws IOException, ServletException {
    HttpServletResponse sresponse = (HttpServletResponse) response;
    sresponse.setHeader(ACCESS_CONTROL_ALLOW_ORIGIN, ALL);
    sresponse.setHeader(ACCESS_CONTROL_ALLOW_METHODS, ALLOWED_METHODS);
    sresponse.setHeader(ACCESS_CONTROL_ALLOW_HEADERS, ALLOWED_HEADERS);
    sresponse.setHeader(ACCESS_CONTROL_EXPOSE_HEADERS, EXPOSE_HEADERS);
    chain.doFilter(request, response);
  }

  public void init(FilterConfig filterConfig) {}

  public void destroy() {}
}