Implementing Ajax Authentication using jQuery, Spring Security and HTTPS

I've always had a keen interest in implementing security in webapps. I implemented container-managed authentication (CMA) in AppFuse in 2002, watched Tomcat improve it's implementation in 2003 and implemented Remember Me with CMA in 2004. In 2005, I switched from CMA to Acegi Security (now Spring Security) and never looked back. I've been very happy with Spring Security over the years, but also hope to learn more about Apache Shiro and implementing OAuth to protect JavaScript APIs in the near future.

I was recently re-inspired to learn more about security when working on a new feature at Overstock.com. The feature hasn't been released yet, but basically boils down to allowing users to login without leaving a page. For example, if they want to leave a review on a product, they would click a link, be prompted to login, enter their credentials, then continue to leave their review. The login prompt and subsequent review would likely be implemented using a lightbox. While lightboxes are often seen in webapps these days because they look good, it's also possible Lightbox UIs provide a poor user experience. User experience aside, I think it's interesting to see what's required to implement such a feature.

To demonstrate how we did it, I whipped up an example using AppFuse Light, jQuery and Spring Security. The source is available in my ajax-login project on GitHub. To begin, I wanted to accomplish a number of things to replicate the Overstock environment:

  1. Force HTTPS for authentication.
  2. Allow testing HTTPS without installing a certificate locally.
  3. Implement a RESTful LoginService that allows users to login.
  4. Implement login with Ajax, with the request coming from an insecure page.

Forcing HTTPS with Spring Security
The first feature was fairly easy to implement thanks to Spring Security. Its configuration supports a requires-channel attribute that can be used for this. I used this to force HTTPS on the "users" page and it subsequently causes the login to be secure.

<intercept-url pattern="/app/users" access="ROLE_ADMIN" requires-channel="https"/>

Testing HTTPS without adding a certificate locally
After making the above change in security.xml, I had to modify my jWebUnit test to work with SSL. In reality, I didn't have to modify the test, I just had to modify the configuration that ran the test. In my last post, I wrote about adding my 'untrusted' cert to my JVM keystore. For some reason, this works for HttpClient, but not for jWebUnit/HtmlUnit. The good news is I figured out an easier solution - adding the trustStore and trustStore password as system properties to the maven-failsafe-plugin configuration.

<artifactId>maven-failsafe-plugin</artifactId>
<version>2.7.2</version>
<configuration>
    <includes>
        <include>**/*WebTest.java</include>
    </includes>
    <systemPropertyVariables>
      <javax.net.ssl.trustStore>${project.build.directory}/ssl.keystore</javax.net.ssl.trustStore>
      <javax.net.ssl.trustStorePassword>appfuse</javax.net.ssl.trustStorePassword>
    </systemPropertyVariables>
</configuration>

The disadvantage to doing things this way is you'll have to pass these in as arguments when running unit tests in your IDE.

Implementing a LoginService
Next, I set about implementing a LoginService as a Spring MVC Controller that returns JSON thanks to the @ResponseBody annotation and Jackson.

package org.appfuse.examples.web;

import org.appfuse.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping("/api/login.json")
public class LoginService {

  @Autowired
  @Qualifier("authenticationManager")
  AuthenticationManager authenticationManager;

  @RequestMapping(method = RequestMethod.GET)
  @ResponseBody
  public LoginStatus getStatus() {
    Authentication auth = SecurityContextHolder.getContext().getAuthentication();
    if (auth != null && !auth.getName().equals("anonymousUser") && auth.isAuthenticated()) {
      return new LoginStatus(true, auth.getName());
    } else {
      return new LoginStatus(false, null);
    }
  }

  @RequestMapping(method = RequestMethod.POST)
  @ResponseBody
  public LoginStatus login(@RequestParam("j_username") String username,
                           @RequestParam("j_password") String password) {

    UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password);
    User details = new User(username);
    token.setDetails(details);

    try {
      Authentication auth = authenticationManager.authenticate(token);
      SecurityContextHolder.getContext().setAuthentication(auth);
      return new LoginStatus(auth.isAuthenticated(), auth.getName());
    } catch (BadCredentialsException e) {
      return new LoginStatus(false, null);
    }
  }

  public class LoginStatus {

    private final boolean loggedIn;
    private final String username;

    public LoginStatus(boolean loggedIn, String username) {
      this.loggedIn = loggedIn;
      this.username = username;
    }

    public boolean isLoggedIn() {
      return loggedIn;
    }

    public String getUsername() {
      return username;
    }
  }
}

To verify this class worked as expected, I wrote a unit test using JUnit and Mockito. I used Mockito because Overstock is transitioning to it from EasyMock and I've found it very simple to use.

package org.appfuse.examples.web;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.mockito.Matchers;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.authentication.TestingAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContext;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.context.SecurityContextImpl;

import static org.junit.Assert.*;
import static org.mockito.Mockito.*;

public class LoginServiceTest {

  LoginService loginService;
  AuthenticationManager authenticationManager;

  @Before
  public void before() {
    loginService = new LoginService();
    authenticationManager = mock(AuthenticationManager.class);
    loginService.authenticationManager = authenticationManager;
  }

  @After
  public void after() {
    SecurityContextHolder.clearContext();
  }

  @Test
  public void testLoginStatusSuccess() {
    Authentication auth = new TestingAuthenticationToken("foo", "bar");
    auth.setAuthenticated(true);
    SecurityContext context = new SecurityContextImpl();
    context.setAuthentication(auth);
    SecurityContextHolder.setContext(context);

    LoginService.LoginStatus status = loginService.getStatus();
    assertTrue(status.isLoggedIn());
  }

  @Test
  public void testLoginStatusFailure() {
    LoginService.LoginStatus status = loginService.getStatus();
    assertFalse(status.isLoggedIn());
  }

  @Test
  public void testGoodLogin() {
    Authentication auth = new TestingAuthenticationToken("foo", "bar");
    auth.setAuthenticated(true);
    when(authenticationManager.authenticate(Matchers.<Authentication>anyObject())).thenReturn(auth);
    LoginService.LoginStatus status = loginService.login("foo", "bar");
    assertTrue(status.isLoggedIn());
    assertEquals("foo", status.getUsername());
  }

  @Test
  public void testBadLogin() {
    Authentication auth = new TestingAuthenticationToken("foo", "bar");
    auth.setAuthenticated(false);
    when(authenticationManager.authenticate(Matchers.anyObject()))
        .thenThrow(new BadCredentialsException("Bad Credentials"));
    LoginService.LoginStatus status = loginService.login("foo", "bar");
    assertFalse(status.isLoggedIn());
    assertEquals(null, status.getUsername());
  }
}

Implement login with Ajax
The last feature was the hardest to implement and still isn't fully working as I'd hoped. I used jQuery and jQuery UI to implement a dialog that opens the login page on the same page rather than redirecting to the login page. The "#demo" locator refers to a button in the page.

Passing in the "ajax=true" parameter disables SiteMesh decoration on the login page, something that's described in my Ajaxified Body article.

var dialog = $('<div></div>');

$(document).ready(function() {
    $.get('/login?ajax=true', function(data) {
        dialog.html(data);
        dialog.dialog({
            autoOpen: false,
	       title: 'Authentication Required'
        });
    });

    $('#demo').click(function() {
      dialog.dialog('open');
      // prevent the default action, e.g., following a link
      return false;
    });
});

Instead of adding a click handler to a specific id, it's probably better to use a CSS class that indicates authentication is required for a link, or -- even better -- use Ajax to see if the link is secured.

The login page then has the following JavaScript to add a click handler to the "login" button that submits the request securely to the LoginService.

var getHost = function() {
    var port = (window.location.port == "8080") ? ":8443" : "";
    return ((secure) ? 'https://' : 'http://') + window.location.hostname + port;
};

var loginFailed = function(data, status) {
    $(".error").remove();
    $('#username-label').before('<div class="error">Login failed, please try again.</div>');
};

$("#login").live('click', function(e) {
    e.preventDefault();
    $.ajax({url: getHost() + "/api/login.json",
        type: "POST",
        data: $("#loginForm").serialize(),
        success: function(data, status) {
            if (data.loggedIn) {
                // success
                dialog.dialog('close');
                location.href= getHost() + '/users';
            } else {
                loginFailed(data);
            }
        },
        error: loginFailed
    });
});

The biggest secret to making this all work (the HTTP -> HTTPS communication, which is considered cross-domain), is the window.name Transport and the jQuery plugin that implements it. To make this plugin work with Firefox 3.6, I had to implement a Filter that adds Access-Control headers. A question on Stackoverflow helped me figure this out.

public class OptionsHeadersFilter implements Filter {

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
            throws IOException, ServletException {
        HttpServletResponse response = (HttpServletResponse) res;

        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "GET,POST");
        response.setHeader("Access-Control-Max-Age", "360");
        response.setHeader("Access-Control-Allow-Headers", "x-requested-with");

        chain.doFilter(req, res);
    }

    public void init(FilterConfig filterConfig) {
    }

    public void destroy() {
    }
}

Issues
I encountered a number of issues when implementing this in the ajax-login project.

  • If you try to run this with ports (e.g. 8080 and 8443) in your URLs, you'll get a 501 (Not Implemented) response. Removing the ports by fronting with Apache and mod_proxy solves this problem.
  • If you haven't accepted the certificate in your browser, the Ajax request will fail. In the example, I solved this by clicking on the "Users" tab to make a secure request, then going back to the homepage to try and login.
  • The jQuery window.name version 0.9.1 doesn't work with jQuery 1.5.0. The error is "$.httpSuccess function not found."
  • Finally, even though I was able to authenticate successfully, I was unable to make the authentication persist. I tried adding the following to persist the updated SecurityContext to the session, but it doesn't work. I expect the solution is to create a secure JSESSIONID cookie somehow.
    @Autowired
    SecurityContextRepository repository;
    
    @RequestMapping(method = RequestMethod.POST)
    @ResponseBody
    public LoginStatus login(@RequestParam("j_username") String username,
                             @RequestParam("j_password") String password,
                             HttpServletRequest request, HttpServletResponse response) {
    
        UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password);
        ...
    
        try {
            Authentication auth = authenticationManager.authenticate(token);
            SecurityContextHolder.getContext().setAuthentication(auth);
            // save the updated context to the session
            repository.saveContext(SecurityContextHolder.getContext(), request, response);
            return new LoginStatus(auth.isAuthenticated(), auth.getName());
        } catch (BadCredentialsException e) {
            return new LoginStatus(false, null);
        }
    }
    

Conclusion
This article has shown you how to force HTTPS for login, how to do integration testing with a self-generated certificate, how to implement a LoginService with Spring MVC and Spring Security, as well as how to use jQuery to talk to a service cross-domain with the window.name Transport. While I don't have everything working as much as I'd like, I hope this helps you implement a similar feature in your applications.

One thing to be aware of is with lightbox/dialog logins and HTTP -> HTTPS is that users won't see a secure icon in their address bar. If your app has sensitive data, you might want to force https for your entire app. OWASP's Secure Login Pages has a lot of good tips in this area.

Update: I've posted a demo of the ajax-login webapp. Thanks to Contegix for hosting the demo and helping obtain/install an SSL certificate so quickly.

Posted in Java at Feb 23 2011, 04:55:55 PM MST 13 Comments

How I Calculated Ratings for My JVM Web Frameworks Comparison

When I re-wrote my Comparing JVM Web Frameworks presentation from scratch, I decided to add a matrix that allows you to rate a framework based on 20 different criteria. The reason I did this was because I'd used this method when choosing an Ajax framework for Evite last year. The matrix seemed to work well for selecting the top 5 frameworks, but it also inspired a lot of discussion in the community that my ratings were wrong.

I expected this, as I certainly don't know every framework as well as I'd like. The mistake I made was asking for the community to provide feedback on my ratings without describing how I arrived at them. From Peter Thomas's blog:

What you are doing is adjusting ratings based on who in the community shouts the loudest. I can't help saying that this approach comes across as highly arrogant and condescending, you seem to expect framework developers and proponents to rush over and fawn over you to get better ratings, like waiters in a restaurant trying to impress a food-critic for Michelin stars.

I apologize for giving this impression. It certainly wasn't my intent. By having simple numbers (1.0 == framework does well, 0.5 == framework is OK and 0 == framework not good at criteria) with no rationalization, I can see how the matrix can be interpreted as useless (or to put it bluntly, as something you should wipe your ass with). I don't blame folks for getting angry.

For my Rich Web Experience presentation, I documented why I gave each framework the rating I did. Hopefully this will allow folks to critique my ratings more constructively and I can make the numbers more accurate. You can view this document below or on Google Docs.

In the end, what I was hoping to do with this matrix was to simply highlight a technique for choosing a web framework. Furthermore, I think adding a "weight" to each criteria is important because things like books often aren't as important as REST support. To show how this might be done, I added a second sheet to the matrix and made up some weighting numbers. I'd expect anyone that wants to use this to downloaded the matrix, verify the ratings are accurate for your beliefs and weight the criteria accordingly.

Of course, as I and many others have said, the best way to choose a web framework is to try them yourself. I emphasized this at the end of my presentation with the following two slides.

Slide #77 from Comparing JVM Web Frameworks Talk at RWX2010

Slide #76 from Comparing JVM Web Frameworks Talk at RWX2010

Posted in Java at Dec 06 2010, 11:55:18 AM MST 10 Comments

My Comparing JVM Web Frameworks Presentation from Devoxx 2010

This week, I've been having a great time in Antwerp, Belgium at the Devoxx Conference. This morning, I had the pleasure of delivering my Comparing JVM Web Frameworks talk. I thoroughly enjoyed giving this presentation, especially to such a large audience. You can view the presentation below (if you have Flash installed) or download it here.

Unlike previous years, I chose to come up with a spreadsheet matrix that shows why I chose the 5 I did. This spreadsheet and rankings given to each framework are likely to be debated, as I don't know all the frameworks as well as I'd like to. Also, the missing column on this spreadsheet is a "weighting" column where you can prioritize certain criteria like I've done in the past when Comparing Ajax Frameworks. If you believe there are incorrect numbers, please let me know and I'll try to get those fixed before I do this talk again at The Rich Web Experience.

One thing that doesn't come across in this presentation is that I believe anyone can use this matrix, and weightings, to make any of these frameworks come out on top. I also believe web frameworks are like spaghetti sauce in The Ketchup Conundrum. That is, the only way to make more happy spaghetti sauce lovers was to make more types of spaghetti sauce. You can read more about this in my There is no "best" web framework article.

Update: If you disagree with the various ratings I gave to web frameworks in this presentation, please provide your opinions by filling out this survey. Thanks to Sebastien Arbogast for setting this up.

Update: Sebastien has posted his survey results at JVM Web Framework Survey, First Results.

Update 12/6: A video of this presentation is now available on Parleys.com.

P.S. My current gig is ending in mid-December. If you're looking for a UI Architect with a passion for open source frameworks, please let me know.

Posted in Java at Nov 18 2010, 05:23:10 AM MST 39 Comments

AppFuse 2.1 Milestone 2 Released

I'm pleased to announce the 2nd milestone release of AppFuse 2.1. This release includes upgrades to all dependencies to bring them up-to-date with their latest releases. Most notable are Spring 3 and Struts 2.1. This release fixes many issues with archetypes and contains many improvements to support Maven 3. For more details on specific changes see the 2.1.0 M2 release notes.

What is AppFuse?
AppFuse is an open source project and application that uses open source frameworks to help you develop Web applications quickly and efficiently. It was originally developed to eliminate the ramp-up time when building new web applications. At its core, AppFuse is a project skeleton, similar to the one that's created by your IDE when you click through a wizard to create a new web project. If you use JRebel with AppFuse, you can achieve zero-turnaround in your project and develop features without restarting the server.

Release Details
Archetypes now include all the source for the web modules so using jetty:run and your IDE will work much smoother now. The backend is still embedded in JARs, enabling you to choose with persistence framework (Hibernate, iBATIS or JPA) you'd like to use. If you want to modify the source for that, add the core classes to your project or run "appfuse:full-source".

AppFuse comes in a number of different flavors. It offers "light", "basic" and "modular" and archetypes. Light archetypes use an embedded H2 database and contain a simple CRUD example. In the final 2.1.0 release, the light archetypes will allow code generation like the basic and modular archetypes. Basic archetypes have web services using CXF, authentication from Spring Security and features including signup, login, file upload and CSS theming. Modular archetypes are similar to basic archetypes, except they have multiple modules which allows you to separate your services from your web project.

AppFuse provides archetypes for JSF, Spring MVC, Struts 2 and Tapestry 5. The light archetypes are available for these frameworks, as well as for Spring MVC + FreeMarker, Stripes and Wicket.

Please note that this release does not contain updates to the documentation. Code generation will work, but it's likely that some content in the tutorials won't match. For example, you can use annotations (vs. XML) for Spring MVC and Tapestry is a whole new framework. I'll be working on documentation over the next several weeks in preparation for the 2.1 final release.

For information on creating a new project, please see the QuickStart Guide.

If you have questions about AppFuse, please read the FAQ or join the user mailing list. If you find bugs, please create an issue in JIRA.

Thanks to everyone for their help contributing patches, writing documentation and participating on the mailing lists.

Posted in Java at Nov 15 2010, 03:28:57 PM MST 2 Comments

RE: Moving from Spring to Java EE 6: The Age of Frameworks is Over

Last Tuesday, Cameron McKenzie wrote an interesting article on TheServerSide titled Moving from Spring to Java EE 6: The Age of Frameworks is Over. In this article, Cameron says the following:

J2EE represents the past, and Java EE 6 represents the future. Java EE 6 promises us the ability to go beyond frameworks. Frameworks like Spring are really just a bridge between the mistakes of the J2EE past and the success of the Java EE 6 future. Frameworks are out, and extensions to the Java EE 6 platform are in. Now is the time to start looking past Spring, and looking forward to Seam and Weld and CDI technologies.

He then links to an article titled Spring to Java EE - A Migration Experience, an article written by JBoss's Lincoln Baxter. In this article, Lincoln talks about many of the technologies in Java EE 6, namely JPA, EJB, JSF, CDI and JAX-RS. He highlights all the various XML files you'll need to know about and the wide variety of Java EE 6 application servers: JBoss AS 6 and GlassFish v3.

I don't have a problem with Lincoln's article, in fact I think it's very informative and some of the best documentation I've seen for Java EE 6.

I do have some issues with Cameron's statements that frameworks are mistakes of the J2EE past and that Java EE 6 represents the future. Open source frameworks made J2EE successful. Struts and Hibernate came out in the early days of J2EE and still exist today. Spring came out shortly after and has turned into the do-everything J2EE implementation it was trying to fix. Java EE 6 might be a better foundation to build upon, but it's certainly not going to replace frameworks.

To prove my point, let's start by looking at the persistence layer. We used to have Hibernate based on JDBC, now we have JPA implementations built on top of the JPA API. Is JPA a replacement for all persistence frameworks? I've worked with it and think it's a good API, but the 2.0 version isn't available in a Maven repo and Alfresco recently moved away from Hibernate (which == JPA IMO) to iBATIS for greater data access layer control and scalability. Looks like the age of frameworks isn't over for persistence frameworks.

The other areas that Java EE 6 covers that I believe frameworks will continue to excel in: EJB, CDI, JSF and JAX-RS. Personally, I don't have a problem with EJB 3 and think it's a vast improvement on EJB 2.x. I don't have an issue with CDI either, and as long as it resembles Guice for dependency injection, it works for me. However, when you get into the space I've been living in for the last couple years (high-traffic public internet sites), EJB and things like the "conversation-scope" feature of CDI don't buy you much. The way to make web application scale is to eliminate state and cache as much as possible, both of which Java EE doesn't provide much help for. In fact, to disable sessions in a servlet-container, you have to write a Filter like the following:

public class DisabledSessionFilter extends OncePerRequestFilter {

    /**
     * Filters requests to disable URL-based session identifiers.
     */
    @Override
    protected void doFilterInternal(final HttpServletRequest request,
                                    final HttpServletResponse response,
                                    final FilterChain chain)
            throws IOException, ServletException {

        HttpServletRequestWrapper wrappedRequest = new HttpServletRequestWrapper(request) {

            @Override
            public HttpSession getSession(final boolean create) {
                if (create) {
                    throw new UnsupportedOperationException("Session support disabled");
                }
                return null;
            }

            @Override
            public HttpSession getSession() {
                throw new UnsupportedOperationException("Session support disabled");
            }
        };

        // process next request in chain
        chain.doFilter(wrappedRequest, response);
    }
}

What about JAX-RS? Does it replace the need for frameworks? I like the idea of having a REST API in Java. However, its reference implementation is Jersey, which seems more like a framework than just Java EE. If you choose to use JAX-RS in your application, you still have to choose between CXF, Jersey, RESTEasy and Restlet. I compared these frameworks last year and found the Java EE implementation lacking in the features I needed.

Finally, let's talk about my-least-framework-web-framework: JSF. The main reason I don't like JSF is because of its 1.x version. JSF 1.0 was released a year before the Ajax term was coined (see timeline below). Not only did it take forever to develop as a spec, but it tried to be a client-component framework that was very stateful by default.

History of Web Frameworks

Now that JSF 2.0 is out, it has Ajax integrated and allows you to use GET instead of POST-for-everything. However, the only people that like Ajax integrated into their web frameworks are programmers scared of JavaScript (who probably shouldn't be developing your UI). Also, the best component development platform for the web is JavaScript. I recommend using an Ajax framework for your components if you really want a rich UI.

Sure you can use the likes of Tapestry and Wicket if you like POJO-based web development, but if you're looking to develop a webapp that's easy to maintain and understand, chances are that you'll do much better with traditional MVC frameworks like Spring MVC and Struts 2. The simplicity and popularity of Rails and Grails further emphasize that developers prefer these types of web frameworks.

Another reason I don't like JSF: there's very few developers in the wild happy with it. The major promoters of JSF are book authors, trainers, Java EE Vendors and MyFaces developers. Whenever I speak at conferences, I ask folks to raise their hands for the various web frameworks they're using. I always ask the JSF users to keep their hands up if they like it. Rarely do they stay up.

So it looks like we still need web frameworks.

Eberhard Wolff has an interesting post where he defends Spring and talks about the productivity comparisons between Spring and Java EE. He recommends using Grails or Spring Roo if you want the level of productivity that Ruby on Rails provides. That's a valid recommendation if you're building CRUD-based webapps, but I haven't developed those in quite some time. Nowadays, the apps I develop are true SOFEA apps, where the backend serves up XML or JSON and the frontend client is HTML/JavaScript/CSS, Android, iPad or Sony Blu-Ray players. On my current project, our services don't even talk to a database, they talk to a CMS via RESTful APIs. We use Spring's RestTemplate for this and HttpClient when it doesn't have the features we need. Not much in Java EE 6 for this type of communication. Sure, Jersey has a client, but it's certainly not part of the Java EE spec.

As far as getting Ruby on Rails' zero-turnaround productivity, I don't need Grails or Spring Roo, I simply use IDEA and JRebel.

Conclusion
I don't see how new features in Java EE 6 can mean the age of frameworks is over. Java SE and J2EE have always been foundations for frameworks. The Java EE 6 features are often frameworks in themselves that can be used outside of a Java EE container. Furthermore, Java EE 6 doesn't provide all the features you need to build a high-scale web app today. There's no caching, no stateless web framework that can serve up JSON and HTML and no hot-reload productivity enhancements like JRebel. Furthermore, there's real excitement in Javaland for languages like Scala, Groovy and JRuby. All of these languages have web frameworks that've made many developers happy.

Here's to the Age of Frameworks - may it live as long as the JVM!

P.S. If you'd like to hear me talk about web frameworks on the JVM, I'll be speaking at The Colorado Springs Open Source Meetup and Devoxx 2010 in the near future.

Posted in Java at Oct 16 2010, 03:19:07 PM MDT 37 Comments

My TSSJS 2010 Presentations and Summary

This afternoon, I delivered my last talk at TSSJS 2010 on The Future of Web Frameworks. It's true that I made some bold statements, but please remember that this is my personal opinion, based on my experience. For the most part, I've been involved in super high-traffic websites for the last few years and this has influenced my opinion on web frameworks. Just because I don't recommend your favorite framework doesn't mean it won't work for you. In fact, many of the best web applications today were built without an open source (or commercial) web framework. In the end, it's not as much about the web framework you're using as it is about hiring smart people. Below is my slide deck from this talk.

Yesterday, I did a GWT vs. Flex Smackdown with James Ward. While there wasn't as much trash talking as I'd hoped, I enjoyed delivering it and disputing the greatness of Flex. Below is the presentation that James and I delivered.

The show itself was great this year. It had more attendees than I've seen in a long time. There were a lot of really interesting sessions and and an often humorous Twitter back-channel. I attended quite a few talks and jotted down my notes from several of them. Please see the links below if you're interested in the sessions I attended. You can view all of the presentations from TSSJS 2010 on SlideShare.

Thanks to everyone who came to Vegas and to TheServerSide for an excellent conference.

Posted in Java at Mar 19 2010, 05:29:08 PM MDT 8 Comments

What's New in Spring 3.0

This morning, I attended Rod Johnson's What's New in Spring 3.0 keynote at TSSJS. Rod ditched his slides for the talk and mentioned that this might be risky. Especially since he was pretty jetlagged (flew in from Paris at 11pm last night). Below are my notes from his talk.

The most important thing for the future of Java is productivity and cloud computing. The focus at SpringSource is heavily on productivity and not just on improving the Spring codebase. If you look at the comparisons out there between Rails and Spring, it's not an apples-to-apples comparison. The philosophy with Spring has always been the developer is always right. However, if you look at something like Rails, you'll see it's far more prescriptive. That layer of opinionated frameworks is important in that it improves your productivity greatly.

SpringSource is putting a lot of emphasis on improving developer productivity with two opinionated frameworks: Grails and Spring Roo. To show how productive developers can be, Rod started to build a web app with Spring Roo. As part of this demo, he mentioned we'd see many of the new features of Spring 3: RestTemplate, @Value and Spring EL.

Rod used STS to write the application and built a Twitter client. After creating a new project using File -> New Roo Project, a Roo Shell tab shows up at the bottom. Typing "hint" tells you what you should do write away. The initial message is "Roo requires the installation of a JPA provider and associated database." The initial command is "persistence setup --provider HIBERNATE --database HYPERSONIC_IN_MEMORY". After running this, a bunch of log messages are shown on the console, most of them indicating that pom.xml has been modified.

The first file that Rod shows is src/main/resources/META-INF/spring/applicationContext.xml. It's the only XML file you'll need in your application and includes a PropertyPlaceHolderConfigurer, a context:component-scan for finding annotations and a transaction manager.

After typing "hint" again, Roo indicates that Rod should create entities. He does this by running "ent --class ~.domain.Term --testAutomatically". A Term class (with a bunch of annotations) is created, as well as a number of *.aj files and an integration test. Most of the files don't have anything in them but annotations. The integration test uses @RooIntegrationTest(entity=Term.class) on its class to fire up a Spring container in the test and do dependency injection (if necessary). From there, Rod demonstrated that he could easily modify the test to verify the database existed.

private SimpleJdbcTemplate jt;

@Autowired
public void init(DataSource ds) {
    this.jt = new SimpleJdbcTemplate(ds);
}

@Test 
public void testDb() {
    jt.queryForInt("SELECT COUNT(0) FROM TERM");
}

Interestingly, after running the test, you could see a whole bunch of tests being run, not just the one that was in the class itself. From there, he modified the Term class to add two new properties: name and searchTerms. He also used JSR 303's @NotNull annotation to make the fields required.

@Entity
@RooJavaBean
@RooToString
@RooEntity
public class Term {

    @NotNull
    private String name;

    @NotNull
    private String searchTerms;
}

Next, Rod added a new test and showed that the setters for these properties were automatically created and he never had to write getters and setters. This is done by aspects that are generated beside your Java files. Roo is smart enough that if you write toString() methods in your Java code, it will delete the aspect that normally generates the toString() method.

To add fields to an entity from the command lie, you can run commands like "field string --fieldName text --notNull" and "field number --type java.lang.Long --fieldName twitterId --notNull". The Roo Shell is also capable of establishing relationships between entities.

After successfully modifying his Entities, Rod started creating code to talk to Twitter's API. He used RestTemplate to do this and spent a good 5 minutes trying to get Eclipse to import the class properly. The best part of this demo was watching him do what most developers do: searching Google for RestTemplate to get the package name to import.

After awkward silence and some fumbling, he opened an existing project (that had the dependencies properly configured) and used Java Config to configure beans for the project. This was done with a @Configuration annotation on the class, @Value annotations on properties (that read from a properties file) and @Bean annotations for the beans to expose. The first time Rod tried to run the test it failed because a twitter.properties file didn't exist. After creating it, he successfully ran the test and successfully searched Twitter's API.

The nice thing about @Configuration is the classes are automatically picked up and you don't need to configure any XML to recognize them. Also, in your Java classes, you don't have to use @Autowired to get @Bean references injected.

After this, Rod attempted to show a web interface of the application. He started the built-in SpringSource tc Server and proceeded to show us Tomcat's 404 page. Unfortunately, Tomcat seemed to startup OK (no errors in the logs), but obviously something didn't work well. For the next few silent moments, we watched him try to delete web.xml from Eclipse. Unfortunately, this didn't work and we weren't able to see the scaffolding the entities that Rod created.

At this point, Rod opened a completed version of the app and was able to show it to us in a browser. You could hear the murmur of the crowd as everyone realized he was about to show the the Twitter search results for #tssjs. Most of the tweets displayed were from folks commenting about how some things didn't work in the demo.

In summary, there's some really cool things in Spring 3: @Configuration, @Value, task scheduling with @Scheduled and one-way methods with @Async.

Final points of SpringSource and VMWare: they're committed to Java and middleware. Their big focus is providing an integrated experience from productivity to cloud. There's other languages that are further along than Java and SpringSource is trying to fix that. One thing they're working on is a private Java cloud that companies can use and leverage as a VMWare appliance.

I think there's a lot of great things in Spring 3 and most users of Roo seem to be happy with it. It's unfortunate that the Demo Gods frowned upon Rod, but it was cool to see him do the "no presentation" approach.

Posted in Java at Mar 19 2010, 11:46:25 AM MDT 2 Comments

Highly Interactive Software with Java and Flex

This morning at TSSJS, I attended James Ward's talk about Highly Interactive Software with Java and Flex. Below are my notes from his talk.

Application have moved from mainframes (hard to deploy, limited clients) to client/server (hard to deploy, full client capabilities) to web applications (easy to deploy, limited clients) to rich internet applications (easy to deploy, full client capabilities).

Shortly after showing a diagram of how applications have changed, James showed a demo of a sample Flex app for an automobile insurance company. It was very visually appealing, kinda like using an iPhone app. It was a multi-form application that slides right-to-left as you progress through the wizard. It also allowed you to interact with a picture of your car (to indicate where the damage happened) and a map (to indicate how the accident happened). Both of these interactive dialogs still performed data entry, they just did it in more of a visual way.

Adobe's developer technology for building RIAs is Flex. There's two different languages in Flex: ActionScript and MXML. ActionScript was originally based on JavaScript, but now (in ActionScript 3) uses features from Java and C#. On top of ActionScript is MXML. It's a declarative language, but unlike JSP taglibs. All you can do with MXML is instantiate objects and set properties. It's merely a convenience language, but also allows tooling. The open source SDK compiler takes Flex files and compiles it into a *.swf file. This file can then be executed using the Flash Player (in browser) or Air (desktop).

The reason Adobe developed two different runtimes was because they didn't want to bloat the Flash Player. Once the applications are running client-side, the application talks to the web server. Protocols that can be used for communication: SOAP, HTTP/S, AMF/S and RTMP/S. The web server can be composed of REST or SOAP Web Services, as well as BlazeDS or LC Data Services to talk directly to Java classes.

To see all the possible Flex components, see Tour de Flex. It contains a number of components: core components, data access controls, AIR capabilities, cloud APIs, data visualization. The IBM ILOG Elixir real-time dashboard is particularly interesting, as is Doug McCune's Physics Form.

Next James showed us some code. He used Flex Builder to create a new Flex project with BlazeDS. The backend for this application was a JSP page that talks to a database and displays the results in XML. In the main .mxml file, he used <s:HTTPService> with a URL pointing to the URI of the JSP. Then he added an <mx:DataGrid> and the data binding feature of Flex. To do this, he added dataProvider="{srv.lastResult.items.item}" to the DataGrid tag, where "srv" is the id of the HTTPService. Then he added a Button with click="srv.send()" and set the layout to VerticalLayout. This was a simple demo to show how to hook in a backend with XML.

To show that Flex can interact with more than XML over HTTP, James wrote a SOAP service and changed <s:HTTPService> to <s:WebService> and changed the "url" attribute to "wsdl" (and adjusted the value as appropriate). Then rather than using {srv.lastResult.*}, he had to bind to a particular method and change it to {srv.getElements.lastResults}. The Button's click value also had to change to "srv.getElements(0, 2000)" (since the method takes 2 parameters).

After doing coding in Flex Builder, James switched to his Census to compare server-execution times. In the first example (Flash XML AS), most of the time was spent gzipping the 1MB XML file, but the transfer time is reduced because of this. The server execution time is around 800ms. Compare this to the Flex AMF3 example where the server execution time is 49ms. This is because the AMF (binary) protocol streamlines the data and doesn't include repeated metadata.

To integrate BlazeDS in your project, you add the dependencies and then map the MessageBrokerServlet in your web.xml. Then you use a services-config.xml to define the protocol and remoting-config.xml to define what Java classes to export as services. To use this in the Flex aplication, James changed <s:WebService> to <s:RemoteObject>. He changed the "wsdl" attribute to "endpoint" and added a "destination" attribute to specify the name of the aliased Java class to talk to. Next, James ran the demo and showed that he could change the number of rows from 2,000 to 20,000 and the load time was still much, much faster than the XML and SOAP versions.

There's also a Spring BlazeDS Integration project that allows you to simply annotate beans to expose them as AMF services.

BlazeDS also includes a messaging service that you can use to create publishers and subscribers. The default channels in BlazeDS uses HTTP Streaming and HTTP Long Polling (comet), but it can be configurable (e.g. to use JMS). There's also an Adobe commercial product that keeps a connection open using NIO on the server and has a binary protocol. This is useful for folks that need more real-time data in their applications (e.g. trading floors).

I thought this was a really good talk by James. It had some really cool visual demos and the demo was interesting in showing how easy it was to switch between different web services and protocols. This afternoon, I'll be duking it out with James at the Flex vs. GWT Smackdown. If you have deficiencies of Flex you'd like me to share during that talk, please let me know.

Posted in Java at Mar 18 2010, 12:29:26 PM MDT 4 Comments

AppFuse 2.1 Milestone 1 Released

The AppFuse Team is pleased to announce the first milestone release of AppFuse 2.1. This release includes upgrades to all dependencies to bring them up-to-date with their latest releases. Most notable are Hibernate, Spring and Tapestry 5.

What is AppFuse?
AppFuse is an open source project and application that uses open source tools built on the Java platform to help you develop Web applications quickly and efficiently. It was originally developed to eliminate the ramp-up time found when building new web applications for customers. At its core, AppFuse is a project skeleton, similar to the one that's created by your IDE when you click through a wizard to create a new web project.

Release Details
Archetypes now include all the source for the web modules so using jetty:run and your IDE will work much smoother now. The backend is still embedded in JARs, enabling you to choose which persistence framework (Hibernate, iBATIS or JPA) you'd like to use. If you want to modify the source for that, add the core classes to your project or run appfuse:full-source.

In addition, AppFuse Light has been converted to Maven and has archetypes available. AppFuse provides archetypes for JSF, Spring MVC, Struts 2 and Tapestry 5. The light archetypes are available for these frameworks, as well as for Spring MVC + FreeMarker, Stripes and Wicket.

Other notable improvements:

Please note that this release does not contain updates to the documentation. Code generation will work, but it's likely that some content in the tutorials won't match. For example, you can use annotations (vs. XML) for dependency injection and Tapestry is a whole new framework. I'll be working on documentation over the next several weeks in preparation for Milestone 2.

AppFuse is available as several Maven archetypes. For information on creating a new project, please see the QuickStart Guide.

To learn more about AppFuse, please read Ryan Withers' Igniting your applications with AppFuse.

The 2.x series of AppFuse has a minimum requirement of the following specification versions:

  • Java Servlet 2.4 and JSP 2.0 (2.1 for JSF)
  • Java 5+

If you have questions about AppFuse, please read the FAQ or join the user mailing list. If you find bugs, please create an issue in JIRA.

Thanks to everyone for their help contributing code, writing documentation, posting to the mailing lists, and logging issues.

Posted in Java at Nov 19 2009, 07:16:36 AM MST 8 Comments

A Letter to the AppFuse Community

The last AppFuse release was way back in May 2008. Many folks have asked when the next release would be ever since. Often, I've said "sometimes this quarter", but obviously, that's never happened. For that, I apologize.

There are many reasons I haven't worked on AppFuse for the past 18 months, but it mostly comes down to the fact that I didn't make time for it. The good news is I'm working on it again and will have a release out sometime this month. Unfortunately, it probably won't be a 2.1 final release, but there's so many things that've changed, I feel like a milestone release is a good idea. Here's a brief summary of changes so far:

  • Changed archetypes to include all source and tests for the "webapp" portion of the application. No more warpath plugin, merging wars and IDE issues. Using "mvn jetty:run" should work as expected.
  • Moved from Spring XML to Annotations.
  • AppFuse Light converted to Maven modules and now depends on AppFuse's backend.
  • Published easier to use archetype selection form in the QuickStart Guide.
  • Published archetype selection form for AppFuse Light. I do plan on combining these forms as soon as I figure out the best UI and instructions for users to choose AppFuse or AppFuse Light.
  • Upgraded all libraries to latest released versions (Spring 3 hasn't had a final release yet).
  • Upgraded to Tapestry 5 thanks to Serge Eby. I still need to complete tests and code generation for tests.
  • Added Compass support thanks to a patch from Shay Banon.
  • Upgraded from XFire to CXF for Web Services.
  • Moved Maven repository to Sonatype's OSS Repository Hosting for snapshots and releasing to Maven Central. There are no longer any AppFuse-specific artifacts, all are available in central.

I realize there's many full-stack frameworks that do the same thing as AppFuse with less code. Examples include Ruby on Rails, Grails, Seam, Spring Roo and the Play framework. However, there seems to be quite a few folks that continue to use AppFuse and it stills serves the community as a nice example of how to integrate frameworks. Furthermore, it helps me keep up with the latest framework releases, their quirks and issues that happen when you try to integrate them. In short, working on it helps me stay up to speed with Java open source frameworks.

For those folks that like the 1.x, Ant-based version of AppFuse, there will not be a 1.9.5 release. I know I promised it for years, but it's simply something I will not use, so I'd rather not invest my time in it. I'm sorry for lying to those that expected it.

So what's the future of AppFuse? Will it continue to integrate web frameworks with Spring and popular persistence frameworks? Possibly, but it seems more logical to align it with the types of Ajax + REST applications I'm creating these days. I'm currently thinking AppFuse 3.0 would be nice as a RESTful backend with GWT and Flex UIs. I might create the backend with CXF, but it's possible I'd use one of the frameworks mentioned above and simply leverage it to create the default features AppFuse users have come to expect.

More than anything, I'm writing this letter to let you know that the AppFuse project is not dead and you can expect a release in the near future.

Thanks for your support,

Matt

Posted in Java at Nov 04 2009, 12:17:17 AM MST 44 Comments