Now and then I see worries regarding using Grails for production apps, even though there are quite a few already out there. For the last few months I have been working on another one. All I can say is, Grails is the least of your worries! In fact, it's the part that 'just works' for the most part.

I won't be able to get into details about the app. But I can say it consists of 34 domain classes, 50+ views and about 2 million records inside a PostgreSQL database. For the first part of the project, I was lucky enough to get the lions share of the Grails programming, while others worked on data and report conversion from the old Access app.

So, not a huge app, but far more than simply serving up pages, or a simple todo list.

The good stuff:

• Lets you get things done. Interactively creating the application is a joy that cannot be described.
  
• Malleable. Take data queries: we use dynamic finders, HQL, SQL - whatever works best in the current context. There are many other instances where Grails doesn't restrict what we want to do.
• Plays nicely. In the end it's just code on a JVM. We can reuse whatever libraries we please, in our case, Jasper Reports, XStream, OpenCSV, and many others. And then package it all up in a war. And of course, run tests using familiar tools like JUnit. The list goes on.
• You get to code in Groovy almost all of the time! This is a huge factor to me.

 The minor problems:

• We started with and are still using Grails 0.5.6, and so there are some minor quirks to live with that have been fixed in later versions.
• I wish I had the speed and reloading capability of 0.6+! Upgrading is a small risk, but one to take later on, we still have too many other things to finish.

I don't know if these are really problems! Just irritations.

It seems the hardest issues were with the other components: PermGen issues, strange performance problems on PostgreSQL (some of the queries are very complex), bizarre problems on different operating systems (OS X for developing locally, Windows Server of some sort for test and production), an odd problem where the redeploy script doesn't work at random times. And many other things. But few that are the fault of Grails.

So stop worrying if you should try Grails, and worry about, oh, the other 80% of things that really deserve the worry!

I wanted to test some Grails 0.6 features, but for some reason the snapshot I downloaded was not upgrading my project properly. I made a copy of my project folder so I could revert to my original code easily. After a series of attempts to upgrade, interspaced with a few 'rm -r' and 'cp -R' commands, I accidentally selected a 'rm -r' command from the history and autocompleted my backup folder in addition to the source folder! I could feel the nerve impulse surge from my brain and down my arm, helpless to stop it reaching its destination - a finger twiched, the return key depressed, and my work evaporated.

The obvious lesson: don't goof around when tired at the end of the day without committing the work first. But now what? Happily for us programmers, we work with text. Using grep for file recovery didn't occur to me, but after a bit of Google inspiration I recovered most of my work. The command looks something like this:

sudo grep -a -B 2 -A 200 'class Lists' /dev/disk0 > classLists.txt

where B == show lines before, A == show lines after and 'class Lists' is the text to search for.

Once I had my work back, it was time to prevent this from ever happening again. A little while later I had a nice rm script on my machine that would move files to the trash. The script comes from http://www.cs.ecu.edu/~collins/rm/rm.html and some outdated instructions are at http://www.oreillynet.com/pub/h/334.

The commands I used to set things up look something like this:

cd ~
mkdir bin
cd bin
curl -o rm "http://www.cs.ecu.edu/~collins/rm.txt"
chmod 700 rm
echo 'alias rm=$HOME/bin/rm' >> ~/.bash_profile
source ~/.bash_profile
 

Now I am a little safer from myself. Hopefully the above instructions will be of use to others.

My poor little computer was at the receiving end of uncharacteristic cursing. This happens when my 'flow' is interrupted too often. Moving between domain classes, controllers and views is rather tedious in Eclipse. So yesterday I did something about it and created some navigation actions, and now I am back in my peaceful coding world.

The actions appear in the Navigation menu, as well as the popup menu in the Groovy editor:



The first action, 'Open Twin' toggles between domain classes and their related controller. The hot key make this very snappy.
The second action, 'Open Views' opens a dialog with a list of views related to the domain or controller class:




In a previous entry, I described how to enable the XML editor for GSPs. If need be I will add more actions to get from GSPs back to their related controller classes.

This is not part of the official GroovyEclipse plugin. I don't know where it fits it - it should be part of GrailsEclipse, but I don't know anything about it. I will have to ask James how that is coming along.

Until then, I created an update site at http://www.rippleinteractive.com/update from which to install the plugin. And if anyone wants to poke around, here is the source.
I'd be curious to know if it works in Windows, I didn't think too hard about path separators.

Have fun.