added consent request builder and redirect in error.jsp views file

Author: AaronWDS

src/main/java/com/docusign/security/jwt/JWTOAuth2RestTemplate.java

@@ -5,10 +5,12 @@
 import com.docusign.esign.client.auth.OAuth;
 import com.docusign.esign.client.auth.OAuth.OAuthToken;
 import com.docusign.exception.LauncherException;
+
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.List;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.security.oauth2.client.OAuth2ClientContext;
@@ -17,6 +19,7 @@
 import org.springframework.security.oauth2.client.resource.UserRedirectRequiredException;
 import org.springframework.security.oauth2.common.DefaultOAuth2AccessToken;
 import org.springframework.security.oauth2.common.OAuth2AccessToken;
+import org.springframework.web.servlet.view.RedirectView;
 
 public class JWTOAuth2RestTemplate extends OAuth2RestTemplate {
 
@@ -44,16 +47,20 @@ public OAuth2AccessToken getAccessToken() throws UserRedirectRequiredException {
                 context.setAccessToken(accessToken);
             } catch (Exception e) {
                 context.setAccessToken(null);
-                throw e;
+                try {
+                    throw e;
+                } catch (LauncherException ex) {
+                    ex.printStackTrace();
+                }
             }
         }
         return accessToken;
     }
 
-    private OAuth2AccessToken accessToken() {
+    private OAuth2AccessToken accessToken() throws LauncherException {
         logger.info("Fetching an access token via JWT grant...");
         List<String> scopes = new ArrayList<>();
-        // Only signature scope is needed. Impersonation scope is implied.
+// Only signature scope is needed. Impersonation scope is implied.
         scopes.add(OAuth.Scope_SIGNATURE);
         byte[] privateKeyBytes;
         try {
@@ -71,11 +78,32 @@ private OAuth2AccessToken accessToken() {
                     privateKeyBytes,
                     TOKEN_EXPIRATION_IN_SECONDS);
         } catch (IOException | ApiException e) {
+// Special handling for consent_required
+            String message = e.getMessage();
+            String consent_url = "";
+            if (message != null && message.contains("consent_required")) {
+                consent_url = String.format("https://%s/oauth/auth?prompt=login&response_type=code&scope=%s" +
+                    "&client_id=%s" +
+                    "&redirect_uri=%s",
+                    resource.getBaseUrl(),
+                    "signature%20impersonation",
+                    resource.getClientId(),
+                    "http://localhost:8080/login%26type%3Djwt");
+                System.err.println("\nC O N S E N T   R E Q U I R E D" +
+                        "\nAsk the user who will be impersonated to run the following url: " +
+                        "\n" + consent_url +
+                        "\n\nIt will ask the user to login and to approve access by your application." +
+                        "\nAlternatively, an Administrator can use Organization Administration to" +
+                        "\npre-approve one or more users.");
+                        throw new AccessTokenRequiredException(consent_url, resource);
+            }
+
             throw new AccessTokenRequiredException(e.getMessage(), resource);
+
         }
         apiClient.setAccessToken(oAuthToken.getAccessToken(), oAuthToken.getExpiresIn());
         logger.info("Done. Continuing...");
-       return convert(oAuthToken);
+        return convert(oAuthToken);
     }
 
     private static OAuth2AccessToken convert(OAuthToken oAuthToken) {

src/main/webapp/WEB-INF/templates/views/error.jsp

@@ -1,11 +1,22 @@
 <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
+<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>
 <jsp:include page="./partials/head.jsp"/>
 
-<p><strong>Example page failure.</strong></p>
 
-<p><em>Error information: </em>${error}</p>
 
-<p>Something wrong with your account credentials.</p>
+<c:set var="message" value='${requestScope["message"]}' />
+<c:if test='${fn:contains(message, "docusign.com/oauth/auth") }'>
+
+    <c:redirect url="${message}" />
+
+</c:if>
+
+
+<p><strong>Oops, we have encountered a problem.</strong></p>
+
+<p><em>Error information: </em>${message}</p>
+
+<p>Please check your account configuration. If you are unable to resolve the problem, file an issue on github.</p>
 
 
 <p><a href="/">Continue</a></p>