The Space For App Developers

Very recently I was looking for a simple and affordable solution to host Java-based services for the mobile version of my LCDS Samples application. Unfortunately, with the Java development, life is not as easy as with PHP where you can get affordable hosting that is managed and secured by your hosting provider. The reality is that with Java you usually end up having a VPS or an instance of a dedicated Linux server (of course Windows would work also). This is certainly a very good solution that gives you a lot of flexibility but you have to remember that the tasks of administering and securing your box are usually on your shoulders. Although I have some knowledge of Unix-type systems, to be honest I wouldn’t feel comfortable doing the whole administration on my own.

So after some research and trying out different options I ended up with an AWS Elastic Beanstalk service provided by Amazon (you can see it in action running here). I’m really excited about this service because it provides an instance of Tomcat (both 6.x and 7.x versions are available) hosted and managed on Amazon’s cloud infrastructure. On top of that and out-of-the-box, it provides a load balancer that will automatically launch additional instances if your application encounters the increased load. Also you have full access to your Tomcat logs and you can receive email notifications with the status and health of your running services.  Another important thing is that it is extremely easy to use, especially when you install the AWS Eclipse plugin that can also work well with Eclipse/Flash Builder.

The good thing is that the cost of all this is not really high, the entry level service is just about $35.27 a month, more details about pricing are available here.

Getting started

Follow these steps to get up and running:

1. Get an account (if  you don’t already have one) with AWS (Amazon Web Services). Once you get an account you can sign up for Elastic Beanstalk via the “Manage Your Account” section.
2. Configure your IDE environment. By default Flash Builder comes with a standard version of Eclipse that has only the JDT available. I suggest downloading the Eclipse IDE for Java EE Developers and to configure FB with this environment. It will give you additional tools to handle Tomcat instances and Java Web Projects, which you can use when developing for Elastic Beanstalk. Configuring FB with a custom installation of Eclipse is really straightforward. Once you download Eclipse from here and you extract it somewhere to your hard drive, you can go to the folder where you have FB installed and find the Adobe Flash Builder 4.5 Plug-in Utility application located in the utilities folder. In my case it is here “/Applications/Adobe Flash Builder 4.5/utilities/Adobe Flash Builder 4.5 Plug-in Utility.app” but it all depends where you have your FB installation and also on what OS you are on. Run this application and it will guide you with a few simple steps through the whole Flash Builder – Eclipse integration process.
3. Install the AWS Eclipse plugin. This can be done directly from Eclipse. Just go to the Help -> Install New Software menu and enter the following update site URL: http://aws.amazon.com/eclipse
   
4. Create a new AWS Java Web Project. After a successful install of the AWS plugin you will have an option to create new AWS projects. Use the wizard available from the top bar of Eclipse (with an AWS icon on it) to create a New AWS Java Web Project. First you will need to enter a project name, and credentials like Access Key ID and Secret Access Key. These values are generated when you sign up for an AWS account and you can copy them from the Security Credentials section of your AWS account.
   You can select the Basic Java Web Application option (see the screenshot above), this will be enough for the LCDS/BlazeDS scenario. More info about other options is available through this site, with an in-depth video tutorial.
5. Configure the LCDS/BlazeDS  environment. In order to do that you need to, copy all necessary jars into the WebContent/WEB-INF/lib folder of the newly created project. In my case I used a turnkey installation of LCDS and I just copied jars from the lcds-samples application and also jars from tomcat/lib/activemq4.1.1, tomcat/lib/jotm2.0.10 and tomcat/lib/lcds (this wouldn’t be necessary for BlazeDS but for LCDS it was required to make the DataServices and Messaging work properly). Next you will also need to copy all configuration files from the WEB-INF/flex folder and the web.xml that has all necessary LCDS/BlazeDS servlets/listeners configured. The important thing to note here is that by default the AWS Elastic Beanstalk service enables only port 80 and HTTP channels; in order to enable other ports that could be required for RTMP channels you can modify the AWS EC2 Security group settings (but that is a topic for another blog post and I will not cover it here). Another solution you have is to stick to the default settings and to configure LCDS services to use only HTTP channels; this is actually what I did for my lcds.riaspace.comservice.    One last thing I had to do to make the LCDS function properly was to create a WebContent/META-INF/context.xml file in which I defined the transaction configuration as in the following snippet:

   <?xml version="1.0" encoding="UTF-8"?>
   <Context reloadable="true">
     <Transaction factory="org.objectweb.jotm.UserTransactionFactory" jotm.timeout="60"/>
   </Context>

6. Deploy your application to the cloud. Once you have the configuration completed and all the services built you can deploy your application directly from Eclipse. Just right-click on the project and select the Amazon Web Services -> Deploy to AWS Elastic Beanstalk… option. Another wizard will pop up that will ask you to specify names for your application and environment.Next you will need to select the server type, which would be AWS Elastic Beanstalk for Tomcat 6 (you also have the option to deploy to Tomcat 7 instances).
   At last you will be able to specify the CNAME of your server (you can assign your own domain name in the DNS configuration, that is actually what I used to get the default lcds-samples.elasticbeanstalk.com configured as lcds.riaspace.com). Another valuable option here is to enter your email address, which will receive notifications of any changes to the service’s state and health.

   

   Now you are ready to click the Finish button and it will start uploading and configuring your application in the cloud. Be aware that this process may take several minutes the first time. Once it is done you will be able to access your services via the following URL: http://yourcname.elasticbeanstalk.com. To redeploy any changes made to your services you just need to follow this last step all over again.

Yesterday I was presenting at GeeCON (Kraków/Poland) conference where I showed how you can build Flex apps that run and connect to Google Java App Engine. With my first example I did a simple servlet based RESTful service that was returning XML document to my HTTPService on Flex side.

At the end I demonstrated one of my examples that I previously wrote for Zend_Amf but this time I ported it to slightly modified version of BlazeDS that works with GAE. I used instructions from Martin Zoldano blog http://martinzoldano.blogspot.com/2009/04/appengine-adobe-blazeds-fix.html.

You can give it a try, the app is hosted here: http://flexnotes.appspot.com/

Google App Engine is really immazing technology, hopefully it will be able to run BlazeDS without hacking soon I know GraniteDS and WebORB with their latest builds are already supporting it.

New version of GraniteDS 1.1 was released yestarday. Granite is an open source alternative to LCDS/BlazeDS Adobe products. It introduces several cool features and the one I like most is Tide framework that allows very tight integration with JBoss Seam framework which runs on the server side. Future versions will also support Spring and EJB3 on similar level as Seam is currently.

Also brand new Granite Eclipse Builder was released, it is very handful eclipse plugin that can generate AS3 classes based on Java Entity beans.

More info can be found on here.

P.