The best explanation to ESB ever.

I've finally managed to reread some of old Udi's articles and suddenly realized that following few lines are the best explanation of what ESB is all about, ever.

I never want to miss it again that is why I repost it right here in my blog.

"it’s all in the message. Forget about remote method invocations and pub-subbing events—down on the wire it’s all just messages. The trick is to think of your system as passing messages at the application level as well.

Asynchronous message passing over queues. It’s really quite simple.

Once you’ve packaged everything into the message, that message can be dynamically routed anywhere, and so can its responses. The application doesn’t need to bind against any specific endpoint—it just drops a message addressed to some logical location. Infrastructure can make sure that messages get to the logical recipient, even if they change physical locations.

That infrastructure is what brings about the “Bus” architectural style between your distributed components."

As Udi says, you have to reread it several dozens of times, until it strikes to you.

Good luck!

Git ftp deploy

With tools like git, NServiceBus, RoR and the rest, life seams to be better then ever.

With git I've managed to setup deployment with a matter of minutes. Just like this: http://blog.wekeroad.com/2009/11/23/deploying-a-web-application-with-git-and-ftp

There are other ways, probably even simplier: http://ayende.com/blog/4836/primitive-git-auto-deploy

Good luck!

Django newby frustrations.

As you might already guessed, I am currently in a process of discovering two technologies I had no experience with before.

This time I met a strange error running a Django tutorial web application: UnicodeDecodeError: 'ascii' codec can't decode byte 0xe0...

The simplest solution to this can be found here: http://victor-k-development.blogspot.com/2010/07/unicodedecodeerror-django.html

But the roots of the problem and an ultimate solution are to be found here: http://stackoverflow.com/questions/4237898/unicodedecodeerror-ascii-codec-cant-decode-byte-0xe0-in-position-0-ordinal

Good luck!

RoR newby frustrations

As usual, trying to adopt something new is really is a frustration. And though Rails is about to be "a breakthrough in lowering the barriers of entry to programming" you will defenitely meet some errors that might stop you on your way.

First thing I met was: "[rake --tasks] rake aborted! no such file to load -- sqlite3/sqlite3_native".

The solution is really simple. Rake is telling you that it can't find a native library for sqlite. Well, just do what you've been told. Give it a sqlite.dll/.so (depends on OS you are). Put it in $ruby_home\bin.

Next thing to immedeately pop up, after I gave it what it wanted was: "[rake --tasks] WARNING: Global access to Rake DSL methods is deprecated." This one is not as obvious as former. Solution to this one is desribed here: http://benwoodall.com/2011/06/rails-global-access-to-rake-dsl-methods-is-deprecated/

That's it for now.

Good luck!

Installing rails on windows

If you tried to install rails with gems and failed with message "...No such file or directory" - dont woly be hapy. Just folllow these instructions: http://stackoverflow.com/questions/849660/how-to-stop-the-gem-utility-from-accessing-my-home-directory

Good luck!

JetBrains dotPeek to rescue.

I don't know how you faced the fact that Reflector is no longer free, but I for one was very-very dissapointed. Now, our favorite JetBrains team comes to rescue with their brand new tool called dotPeek.

Go and get it here.

PS. Five minutes later I found another tool that will compete to take Reflector's place - JustDecompile from Telerik. It is here.

PPS. Also, there is a work being done for Silverlight by Denis Vuyka and there is another OSS tool to compete for our souls - ILSpy.

PPPS. Life is good again.

Good luck.

NServiceBus Saga Idempotency

Should your business entities had a natural identifier (I think even a surrogate one would do in this case), it would be trivial to ensure idempotency of sagas, that drive their processing.

Just store that Id in a temporal saga storage and enqueue a handler that will guard your sagas as the first handler in NServiceBus endpoint pipe. Something like this one:

And don't forget to specify message handling order:

Good luck!