Add Http Basic Authentication to servletRequest

问题

I have a ProxyServlet to handle requests to another server (which uses HTTP Basic Authentication) sent from my Application, and i want to add the header manually before the Servlet fires the actual request so the User wont have to enter any credentials.

I have tried something like this code below using HttpServletRequestWrapper

public class DataServlet extends ProxyServlet {
  @Override
  protected void service(HttpServletRequest servletRequest, HttpServletResponse servletResponse)
        throws ServletException, IOException {

    final SystemCredentials credentials = new SystemCredentials("username", "password");

    HttpServletRequestWrapper wrap = new HttpServletRequestWrapper(servletRequest){

        @Override
        public String getHeader(String name) {              
            if (name.equals("Authorization")){
                String encoding = Base64.getEncoder().encodeToString((credentials.getUser().concat(":").concat(credentials.getPassword()).getBytes()));
                return "Basic " + encoding;
            } else
                return super.getHeader(name);
        }

    };

    super.service(wrap, servletResponse);

  }
}

It doesnt seem to work, when i try to access it, shows a pop-up and asks for credentials for the remote server.

My web.xml contains

<servlet>
  <servlet-name>data</servlet-name>
  <servlet-class>foo.package.servlet.DataServlet</servlet-class>
  <init-param>
    <param-name>targetUri</param-name>
    <param-value>http://fooServer/DataServer</param-value>
  </init-param>
  <async-supported>true</async-supported>
</servlet>
<servlet-mapping>
  <servlet-name>data</servlet-name>
  <url-pattern>/DataServer/*</url-pattern>
</servlet-mapping>

Is there any other way to make this work?

Thanks!

回答1:

Solution was to override the methods getHeader(String name) , getHeaders(String name) and getHeaderNames() as shown below. This depends also on how the implementation is looking for headers. In this case ProxyServlet is looking via Enumeration<String> getHeaders(String name).

HttpServletRequestWrapper wrap = new HttpServletRequestWrapper(servletRequest){


        @Override
        public String getHeader(String name) {

            if (name.equals(HttpHeaders.AUTHORIZATION)){
                String encoding = Base64.getEncoder().encodeToString((credentials.getUser().concat(":").concat(credentials.getPassword()).getBytes()));
                return "Basic " + encoding;
            }
            return super.getHeader(name);
        }

        @Override
        public Enumeration<String> getHeaders(String name) {
            if (name.equals(HttpHeaders.AUTHORIZATION)){
                List<String> temp = new ArrayList<>();
                String encoding = Base64.getEncoder().encodeToString((credentials.getUser().concat(":").concat(credentials.getPassword()).getBytes()));
                temp.add("Basic " + encoding);
                return Collections.enumeration(temp);
            }
            return super.getHeaders(name);
        }

        @Override
        public Enumeration<String> getHeaderNames() {
            // TODO Auto-generated method stub
            List<String> temp = Collections.list(super.getHeaderNames());
            temp.add(HttpHeaders.AUTHORIZATION);
            return Collections.enumeration(temp);

        }

    };

来源：https://stackoverflow.com/questions/44178257/add-http-basic-authentication-to-servletrequest