在Heroku上启用Java JAX-RS API上的CORS请求

Question

我有一个Java的web应用程序，我正在将一些请求从jQuery发送到配置有JAX-RS的Rest API，在我的本地机器上它运行得很好，但是在Heroku上部署它之后，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向这个endpoint发送一个POST请求。

我也为我的应用程序配置了CORS过滤器，这使得它可以在我的本地机器上工作（在这样做之前，应用程序在我的本地机器上给了我同样的错误）。总之，这里是我如何配置它的

@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");
}

}

我还尝试将这些头添加到响应对象中，作为对请求的响应，但没有成功。

我相信一定是什么Heroku的东西，但我不确定。

任何帮助都是有价值的。

Answer 1

使用普通筛选器：

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() {}
}