wso2 podcast

Here’s a podcast that Dana Gardner did with Ron Schmelzer, senior analyst at ZapThink, and Paul Fremantle, co-founder and vice president of technology at wso2.   The transcript is here.

wso2 ESB

Having found Apache Synapse yesterday, I found wso2 ESB today.  It’s built on Synapse and includes a web front end for configuration and management.  The samples work and managing the ESB through the web front end is comfortable - no code required.  In a real world environment, I’d be nervous about configuring the ESB through the web front end - I favour some sort of release process with testing, provision for rollback to last known good configuration and so forth.  Since you can see the XML configuration, a controlled release process is possible.

Executable XML

Earlier I posted about Synapse.  My biggest concern about Synapse is that there is a lot of XML to write.  To be fair, this is hardly a unique characteristic of Synapse.  nspectre is primarily configured in XML - although you can write your own implementation of IConfigurationReader if you prefer something else.   With the advent of .NET 3.0 XAML is a development that can’t be ignored.

So, all this XML is a great thing, right?  Er, well, no.  I don’t think so.  In a lot of cases, we are using XML as the basis of a DSL - which means that the XML is code.  And that means it gets executed.  And here’s the issue - how do you test all that code?  The unit testing support that is standard fare in most modern languages is absent in this space.  We know what happens when you don’t unit test.  And this gets even worse when the XML is generated by a tool, because in addition to the unit testing issue, it can become difficult to diff - which makes bug detection even harder.  (I should just add a quick note about nspectre here.  Since it generates code at runtime for use by .NET code, it is relatively straightforward to unit test the logic expressed in the configuration - which means you can write unit tests that express the intent and if you change the config in a way that breaks the tests then you know you have a problem.)

I also get the feeling that sometimes XML is being used to add a dynamic capability to static languages.  If that is the case, then shouldn’t we be using languages that have the features we want?

I like flexibility as much as the next person, but I’m concerned about anything that is a block to change.  And executable XML often falls into this category.  Proceed with caution.

Synapse

I came across Synapse yesterday.  There’s a good overview of Synapse on the IBM site here.  This morning I downloaded the 1.0 release and followed a few of the many examples.  The first observation is that Synapse starts up quickly and the samples I tried worked.  The second observation is that it seems very powerful - especially the ability to specify dynamic elements of the configuration in external XML files (here’s an example.)  You can also use languages like Javascript, Ruby and Python to extend Synapse, courtesy of the Bean Scripting Framework - here’s an example using Ruby.

So, first impressions are good.  This is a framework that doesn’t get in the way and works as I’d hope.  I’ve looked at other ESBs and they’ve either made my eyes bleed because of their complexity or I couldn’t really see that they would play nicely with .NET - ok, they all play nicely with .NET if you restrict yourself to web services, but then you lose so much of what many ESBs offer.

Feedburner

Since WordPress.com retired feedstats, I, like Ben, have set up a feedburner feed.  If you’re currently subscribed, it’d be great if you could update your feed.  The new feed location is:

http://feeds.feedburner.com/Remark

Request-Response with ActiveMQ and NMS

I’ve posted an article about how to implement request-response with ActiveMQ and NMS.   Read it here.

Reading habits

I’ve just changed my feed reader.  I’d been using JetBrains Omea Pro until recently and Omea Reader before it.  I tried a bunch of online readers, but never got on with them.  I tried using a desktop reader at home and at work, but the lack of synchronisation was too painful.  At home, I need a Mac based reader.  So I’ve settled on NetNewsWireLite for now, and the web based NewsGator Online for PC access.  I wish I’d figured this arrangement out a little sooner.

What kind of programmer are you?

If you have a few minutes to spare, this short test will fill them.  For the record, I am a DHSB:

"You’re a Doer.
You are very quick at getting tasks done.  You believe the outcome is the most important part of a task and the faster you can reach that outcome the better.  After all, time is money.

You like coding at a High level.
The world is made up of objects and components, you should create your programs the same way.

You work best in a Solo situation.
The best way to program is by yourself.  There’s no communication problems, you know every part of the code allowing you to write the best programs possible.

You are a liBeral programmer.
Programming is a complex task and you should use white space and comments as freely as possible to help simplify the task.  We’re not writing on paper anymore so we can take up as much room as we need."

Spring time

The 1.1 M1 (Milestone 1) version of the Spring .NET framework has been released.  This includes the Spring .NET Web framework, which is well worth a look.  There are a lot of frameworks that seek to replace ASP.NET.  While this may be a good idea, ASP .NET not being the simplest web framework in the world, it can lead to problems - not least with available developer skills.  Spring’s approach is to improve on and extend ASP .NET.  I looked at this over a year ago, and it was apparent then that this approach works.  Of course, it’s not just the web framework, there’s lots more (maybe too much) to get to grips with.

Parallels 3.0 release

Parallels Desktop for Mac v3.0 has been released.  More info here.