zumbrunn.com - e4xd and jhino - javascript server-side soft-coding

e4xd and jhino - javascript server-side soft-coding

A new and experimental core for a complete rewrite of Openmocha.

The e4xd sub-project provides the javascript server-side for the Openmocha project, a javascript application server with a "soft-coding" framework.

The soft-coding allows modifications and development work from the "inside" of the running web application. The behavior of the web application can be changed in ways that closely relates to the hierarchical content structure of the resulting website, without the need to "hard-code" these changes in code files.

Every content object becomes "sovereign" and can define its own behavior, overriding what it would inherit from the hard-coded prototypes or from other soft-coded objects higher up in the content structure hierarchy.

The e4xd objectengine leverages naming conventions for hard-coded filenames and soft-coded object property names to overlay the hard-coded and soft-coded properties and methods and determine the behavior of an object at runtime.

Internally, these conventions follow the existing ones of the Helma framework, but expand that philosophy, adding additional conventions and accomodating to the needs of the soft-coding environment.

The jhino sub-project provides a base application scaffold for the soft-coding environment. It leverages the e4xd object engine and adds an additional layer of conventions, resulting in a basic scaffold for a working base application with CRUD type functionality and access control. Basically, jhino already provides a fully working soft-coding environment, but requires the standard Helma development tools such as the shell and inspector to do the actual "soft-coding".

The e4xd javascript server-side currently requires a patched version of Helma and Rhino. In the case of Rhino, e4xd depends on the JOMP patch and Helma needs to be modified to do the additional file suffix mapping required by e4xd.

Getting Started

You need to have Java installed
download Openmocha
extract the downloaded archive
execute ./start.sh (or start.bat on Windows)
create an admin account at http://localhost:8080/exampleapp/register
copy the authentication code to the server.properties file
login at http://localhost:8080/exampleapp/login

Prerequisites and System Requirements

To run OpenMocha a Java Virtual Machine 1.4 or better is required.

For FreeBSD and other operating systems with ports collection you may install a JRE or JDK from the ports collection. For Windows, Linux and Solaris you can get a Java runtime or development kit from http://java.sun.com/j2se/downloads/. If you are on Mac OS X then you already have a Java runtime that will work well with OpenMocha.

While you can integrate OpenMocha with other tools such as Apache and MySQL, you do not have to. OpenMocha is pre-configured to be deployed on its own and comes with a built-in object oriented database and web server.

Getting started with OpenMocha

On the e4xd.org site, you should be able to find a working build to download and simply start with ./start.sh

http://e4xd.org/

For FreeBSD, Linux, Solaris, Mac OS X and other Unix flavors, start the Helma framework by invoking ./start.sh from the command line. On Windows, invoke start.bat instead.

If the java command can not be found, make sure the JAVA_HOME environment variable is set to the location of your Java installation.

With Helma running, you should be able to connect using your browser and the URL http://127.0.0.1:8080/ or http://localhost:8080/

To initialize the setup, complete the user registration form at http://127.0.0.1:8080/exampleapp/register and follow the instructions to copy the security information into the server.properties file. You may then login to your new OpenMocha server via http://127.0.0.1:8080/exampleapp/login and start configuring and deploying your web applications.

Installing jhino modules in a existing Helma setup

In addition to the full openmocha build, there is also a build that contains only the jhino modules and patched jar files, in order to add jhino to your own helma install. You would need to replace the helma.jar and rhino.jar in your Helma install with the patched versions. The "objectengine" and "jhino" modules are expected to be placed in Helma's modules directory and the exampleapp would normally go into Helma's apps directory. You could then start the example app from your manage application or add it to the apps.properties file to have it start automatically.

http://localhost:8080/exampleapp

More info and help

Other than what you find on the (possibly not yet existing) e4xd.org website, the best places to get in touch are the openmocha mailing list and google group or the #helma@irc.freenode.net IRC channel .

Also, in case you are new to Helma, you of course need to add the helma.org website and mailing lists to the top of that list.

http://helma.org/

To get in touch with me directly, you should find additional contact information on the zumbrunn.com site.

Chris Zumbrunn < chris@zumbrunn.com > https://zumbrunn.com

22.1.2008, 16:35

Even more Server-side Javascript with Jaxer

Coincidence has it that there is even more server-side Javascript news right now: Jaxer

It is basically Mozilla running behind Apache on the server-side, extended with the server-side functionality you would expect, like reading/writing files, db access and other external communication. But since the server-side runs inside a full fledged browser environment, with not only the DOM but CSS and all the client-side js functionality, including XMLHTTP requests and the whole bit, you can really work on both sides with less mental switching.

Take a look at the example John Resig mentions :

<html>
<head>
  <script src="http://code.jquery.com/jquery.js" runat="both"></script>
  <script>
    jQuery(function($){
      $("form").submit(function(){
        save( $("textarea").val() );
        return false;
      });
    });
  </script>
  <script runat="server">
    function save( text ){
      Jaxer.File.write("tmp.txt", text);
    }
    save.proxy = true;
    
    function load(){
      $("textarea").val(
        Jaxer.File.exists("tmp.txt") ? Jaxer.File.read("tmp.txt") : "");
    }
  </script>
</head>
<body onserverload="load()">
  <form action="" method="post">
    <textarea></textarea>
    <input type="submit"/>
  </form>
</body>
</html>

Maybe sometimes it really helps to see both the client-side and server-sider code together like this, without the need to switch between separate files for views and controls. That's something to keep in mind for Jhino. With the older versions of Openmocha you always had the server-side and client-side code together on one page when using the web-based editor. With Jhino we currently lost that. So, this is one good argument to bring back a gui editor where one can see all the properties and behaviors of a Mocha object at a glance.

I'm not sure how often it will really make sense to run the code on both the client and server side. I hope we will come up with some interesting use cases for this, because the idea is intriguing!

23.1.2008, 13:07

Openmocha and Jhino updated to 0.8

New versions of the Openmocha and Jhino javascript server-side packages are available to download . They now contain basic support for fetchlets and many bug fixes:

Added support for fetchlets, javascript functions that are invoked on the client-side but run on the server-side.
added sendScript method, which renders a script to be sent to the clientside
turned the rhino.debug property for the exmapleapp back on, since the debugger is now working again
fixed render method to always return an xml object
fixed breadcrumbs to be properly combined in a div and changed stylesheet accordingly
changed initial registration process to be more distinct from the normal login/register experience
added experimental support for clientside and serverside filename extensions
changed Page to Scaffold in order to work around a problem where the page prototype overrides the one in an applications main repository if the jhino module is added via an app.addRepository call
added workaround for Helma bug #598, which causes onInit on the root object to fail
fixed lists to be contained in ul-element as intended and to use an items title and only fallback on the name if there is no title
updated rhino to latest cvs head with debugger related bug fixes
updated helma to current svn trunk and added fetchlet support

4.2.2008, 1:05

Asynchronous Beer and Geeking and other opportunities to talk about Helma, Rhino and Javascript on the server-side

What's the one senseful thing to do if you live anywhere remotely near a pub called "The Rhino"? Exactly, you go there to talk about Rhino and the wonderful things you can do with it on the server-side thanks to Helma . For example, you can do this at The Rhino in Toronto , where Kristan "Krispy" Uccello initiated a meetup of Javascript geeks to take place every second Monday evening of the month.

The next Ajax Pub Nite is February 11, 2007 at 7pm in Toronto at The Rhino.

If you live at the other end of the world, I'm sure Maksim Lin's talk on Web Development with Helma would be another excellent opportunity for Rhino chatter. I assume that takes place somewhere in Melbourne, Australia, but the exact place and time is yet to be announced.

Then there would be another chance at the OpenExpo in Berne , Switzerland, where I'll be presenting the Helma project on the 12th and 13th of March 2008.

And if you are at Lift'08 this week, I won't mind talking about Helma there either :-)

5.2.2008, 11:56

Solar cell directly splits water for hydrogen

"Plants trees and algae do it. Even some bacteria and moss do it, but scientists have had a difficult time developing methods to turn sunlight into useful fuel. Now, Penn State researchers have a proof-of-concept device that can split water and produce recoverable hydrogen."

http://wattwatt.com/pulses/236/solar-cell-directly-splits-water-for-hydrogen/

26.2.2008, 18:56

Adobe's position on ES4 features, plus the Flex 3 SDK source code is now available under the MPL

Larsen Hansen and Jeff Dyer have issued a position statement outlining Adobe's point of view on how the ECMA TG1 should proceed towards ES4 . Looks reasonable to me.

Plus the Flex 3 SDK source code is now available under the MPL and includes tools to disassemble .swf Flash files. It also contains the code for the actionscript compiler. Note that they messed up, however, and the compiler modules are missing in the released download package. They have since added the missing files to the subversion repository . So, you'll need to check it out from there .

26.2.2008, 20:42