title: OAuth2 spring security with google callback not working
body: <p>i have developed the micro service application, in that application there is a service call user service which is running on port <code>8281</code>. This service handle the authentications. when i test the service in local environment this is worked fine. But if i call this service using zuul api gateway this is not working. following property in the <code>application.yml</code> file is use to get the redirect url in the local environment. This is worked fine. </p>
  
  <pre><code>  security:
      oauth2:
        client:
          registration:
            google:
              redirectUri: "http://localhost:8281/oauth2/callback/google"
  </code></pre>
  
  <p>But if i change this property as follow for connect with zuul api gateway.</p>
  
  <pre><code>  security:
      oauth2:
        client:
          registration:
            google:
              redirectUri: "http://localhost:8080/api/user/oauth2/callback/google"
  </code></pre>
  
  <p>This is not working and is throw this error message <code>[authorization_request_not_found]</code>. localhost:8080 is the zuul api gateway. zuul has configure to forward request to user service like this.</p>
  
  <pre><code>zuul:
    prefix: /api
    routes:
      auth-service:
        path: /user/**
        serviceId: USER-SERVICE
        stripPrefix: true
        sensitiveHeaders: Cookie,Set-Cookie
  </code></pre>
  
  <p>so why this error is thrown ? </p>