OpenID Connect Examples using Multiple Providers?

Question

I'm trying to figure out how to use the Google OAuth Client Library for Java to authenticate against multiple OpenID connect providers. The example they have here works with Daily Motion. I'd like to see how it works with other providers so I can abstract the differences.

Are there any other examples around that authenticate against say Google perhaps?

Answer 1

At this repo, is an example of how to do this using their library. Here's the code from the main sample:

package com.google.api.services.samples.dailymotion.cmdline;

import com.google.api.client.auth.oauth2.AuthorizationCodeFlow;
import com.google.api.client.auth.oauth2.BearerToken;
import com.google.api.client.auth.oauth2.ClientParametersAuthentication;
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.extensions.java6.auth.oauth2.AuthorizationCodeInstalledApp;
import com.google.api.client.extensions.jetty.auth.oauth2.LocalServerReceiver;
import com.google.api.client.http.GenericUrl;
import com.google.api.client.http.HttpRequest;
import com.google.api.client.http.HttpRequestFactory;
import com.google.api.client.http.HttpRequestInitializer;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.JsonObjectParser;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.util.store.DataStoreFactory;
import com.google.api.client.util.store.FileDataStoreFactory;

import java.io.IOException;
import java.util.Arrays;


/**
 * A sample application that demonstrates how the Google OAuth2 library can be used to authenticate
 * against Google.
 *
 * @author Brad Parks
 */
public class GoogleAuthExample {

  // **********************************************************************
  // CHANGE THE FOLLOWING values to the keys you get after following the steps at the following page:
  // https://developers.google.com/accounts/docs/OAuth2Login#appsetup
  // This should be all you need to do to get this sample to work.
  // **********************************************************************
  public static final String API_KEY = "Enter your key here";
  public static final String API_SECRET = "Enter your key here";

  /** Directory to store user credentials. */
  private static final java.io.File DATA_STORE_DIR =
      new java.io.File(System.getProperty("user.home"), ".store/google_oauth_sample");

  /**
   * Global instance of the {@link DataStoreFactory}. The best practice is to make it a single
   * globally shared instance across your application.
   */
  private static FileDataStoreFactory DATA_STORE_FACTORY;

  /** OAuth 2 scope. */
  private static final String SCOPE = "openid email profile https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/userinfo.profile";

  /** Global instance of the HTTP transport. */
  private static final HttpTransport HTTP_TRANSPORT = new NetHttpTransport();

  /** Global instance of the JSON factory. */
  static final JsonFactory JSON_FACTORY = new JacksonFactory();

  private static final String TOKEN_SERVER_URL = "https://accounts.google.com/o/oauth2/token";
  private static final String AUTHORIZATION_SERVER_URL = "https://accounts.google.com/o/oauth2/auth";
  public static final int PORT = 8080;
  public static final String DOMAIN = "127.0.0.1";


  /** Authorizes the installed application to access user's protected data. */
  private static Credential authorize() throws Exception {
    errorIfNotSpecified();

    AuthorizationCodeFlow flow = new AuthorizationCodeFlow.Builder(BearerToken
        .queryParameterAccessMethod(),
        HTTP_TRANSPORT,
        JSON_FACTORY,
        new GenericUrl(TOKEN_SERVER_URL),
        new ClientParametersAuthentication(
            API_KEY, API_SECRET),
        API_KEY,
        AUTHORIZATION_SERVER_URL).setScopes(Arrays.asList(SCOPE))
        .setDataStoreFactory(DATA_STORE_FACTORY).build();

    // authorize
    LocalServerReceiver receiver = new LocalServerReceiver.Builder().setHost(DOMAIN).setPort(PORT).build();
    return new AuthorizationCodeInstalledApp(flow, receiver).authorize("user");
  }

  public static void errorIfNotSpecified() {
    if (API_KEY.startsWith("Enter ") || API_SECRET.startsWith("Enter ")) {
      System.out.println(
          "Enter API Key and API Secret from https://developers.google.com/accounts/docs/OAuth2Login#appsetup"
          + " into API_KEY and API_SECRET in " + GoogleAuthExample.class);
      System.exit(1);
    }
  }

  private static void run(HttpRequestFactory requestFactory) throws IOException {
    GenericUrl url = new GenericUrl("https://www.googleapis.com/oauth2/v1/tokeninfo");

    HttpRequest request = requestFactory.buildGetRequest(url);
    UserInfo userInfo = request.execute().parseAs(UserInfo.class);

    System.out.println("Got user info from API after authorization:");
    System.out.println("-----------------------------------------------");

    System.out.println("issued_to: " + userInfo.issued_to);
    System.out.println("audience: " + userInfo.audience);
    System.out.println("user_id: " + userInfo.user_id);
    System.out.println("scope: " + userInfo.scope);
    System.out.println("expires_in: " + userInfo.expires_in);
    System.out.println("email: " + userInfo.email);
    System.out.println("verified_email: " + userInfo.verified_email);
    System.out.println("access_type: " + userInfo.access_type);
  }

  public static void main(String[] args) {
    try {
      DATA_STORE_FACTORY = new FileDataStoreFactory(DATA_STORE_DIR);
      final Credential credential = authorize();
      HttpRequestFactory requestFactory =
          HTTP_TRANSPORT.createRequestFactory(new HttpRequestInitializer() {
            @Override
            public void initialize(HttpRequest request) throws IOException {
              credential.initialize(request);
              request.setParser(new JsonObjectParser(JSON_FACTORY));
            }
          });
      run(requestFactory);
      // Success!
      return;
    } catch (IOException e) {
      System.err.println(e.getMessage());
    } catch (Throwable t) {
      t.printStackTrace();
    }
    System.exit(1);
  }
}

UserInfo.java

package com.google.api.services.samples.dailymotion.cmdline;

import com.google.api.client.util.Key;

public class UserInfo {
  @Key
  public String issued_to;

  @Key
  public String audience;

  @Key
  public String user_id;

  @Key
  public String scope;

  @Key
  public Integer expires_in;

  @Key
  public String email;

  @Key
  public Boolean verified_email;

  @Key
  public String access_type;
}