Tips when using curl to do an HTTP POST !

I have been playing with RestEasy stuff a bit lately and to test my RESTful webservices, I was using curl to do a HTTP GET and POST. To add to the fun, I wanted to use a YAML file as POST payload. I will talk about YAML and RestEasy in a separate blog post, but when you do a POST as


curl -X POST -d @/home/prabhat/house.yaml -H "Content-type: text/x-yaml" http://localhost:8080/eejot-rest/rest/houses


curl strips all newline which is what a browser does. YAML depends on new line and white spaces so that would result into all sort of deserialization issues on server side. The correct way to do instead is


curl -X POST --data-binary @/home/prabhat/payload.yaml -H "Content-type: text/x-yaml" http://localhost:8080/eejot-rest/rest/houses

Curl man page is very clear on this but sometimes we tend to have false assumption. RTFM Prabhat!

How to delete a svn repo and recover it

I woke up this morning and before I had my coffee, I did something like following:

svn delete .
svn commit -m "some clean up"

As I said I did this before I had my coffee. ;-) But why would I do such thing? SVN showed M for . because I was playing with some svnignore stuff. The above command completely wiped out the branch I was working on. When I realized what I did, I did not need coffee anymore.

After little googling, I did following

svn cp -m "restore.." https://eejot.org/branches/my-branch@110 https://eejot.org/branches/my-branch

where 110 is x-1 with x being the revision number which nuked the branch I was working on.

Winning changes everything !!

India won 2011 World Cup Cricket and I am really really happy for Indian team specially Sachin Tendulkar. I am from Nepal but I grew up following Indian cricket since cricket was not very popular in Nepal back then and Nepali team is not good enough yet to qualify for the world cup.

I would like to think that I played a part in India's victory. Whenever I watched a crucial match, India lost most of the time. It used to hurt a lot; 1996 semi final against Sri Lanka, 2003 world cup final against Australia and 2007 world cup in West Indies come to my mind. So I made a decision this time that I would not watch any live match involving India. This was obviously very difficult but I really wanted Sachin to have his hands on the trophy like millions of Indian people as well as many non Indian avid cricket fans. I am no longer going to do this stupid thing anymore and will just try to enjoy the game. Here is wishing Nepali cricket team to shine so that I have my own country to root for.

When India was loosing many crucial matches and some regular matches abroad, several pundits would sing in chorus on bad infrastructures in India, Indian team lacking self belief, Australian team being mentally tougher, Australian team having good bench strength etc etc. I do believe some of them to be partly correct but I never agreed that they were to the extreme these pundits thought they were. Now that India has won, same pundits are singing the chorus other way around.

I believe teams go through cycle. Some naturally gifted players emerge and they form the core of a team which help them win more matches than they would have otherwise. Of course having good infrastructures and bench strength help but they don't disappear all of sudden when you loose. Australia loosing its dominance has more to do with its core team members (Waugh, Warne, McGrath) retiring in quick succession which is analogous to what happened to West Indies team and which is likely going to be the case for Indian team (primarily in Test cricket) when Tendulkar, Dravid, Laxman retire.

Richfaces showcase on Cloudbees

To continue with my experiments with different PAAS providers, I took Run@Cloud provided by Cloudbees for a ride this time. Overall its web interface is very straightforward and intuitive and similar to what I mentioned about AWS Elastic Beanstalk . I was able to deploy Richfaces 4 Showcase application in couple of minutes and you can see in action at http://showcase.eejot.cloudbees.net.  Once your app is running, besides application logs, you can monitor different operational parameters such as system load, number of request, session etc as evident in following screen shot:

Keep in mind that I did not try its SDK  which allows you to deploy your webapp from command line on your local box.

I found it a bit odd that when you add a new application, the wizard asks you for app name only and not the actual deployable. The advantage of this approach is that you get a running URL immediately to which you can upload your .war. I would have merged these two steps into one.

I also would have liked to have a shell access to actual server as well as ability to specify different JVM parameters. May be it's a work in progress? ;-)

Richfaces showcase on Amazon's Elastic Beanstalk

Richfaces 4 is around the corner and it runs pretty much same in both Tomcat and JBoss. The major difference is that with Tomcat, you have to bundle in your .war a JSF implementation which could be Mojarra or MyFaces. I don't have a preference on JSF implementation at this stage.  Given that Richfaces runs without problem on Tomcat, I thought I should take AWS Elastic Beanstalk for a ride. As it turns out deploying is as simple as deploying it to your local tomcat instance which is a good thing but it also differs a bit.

In following screen shot, you can see that  I have chosen Richfaces showcase application (showcase.war) which I want to deploy on a 32-bit Linux OS running Tomcat 6. Once app is deployed, it should be deployed on http://prabhat.elasticbeanstalk.com (I have shut down my instance so link wont work).

When I deployed my app, I expected my app to be available at http://prabhat.elasticbeanstalk.com/showcase in line with what I get when I deploy the app locally which is http://localhost:8080/showcase . But Beanstalk renames the .war and deploys it as /usr/share/tomcat6/webapps/ROOT which is why it's available under root context . This is important to know because in the next step of configuration, you would  need to supply the URL which can be used for health check. I initially provided /showcase and I ran into problem. Following is what should be:

Other noteworthy differences or rather limitations are that currently Beanstalk configuration does not give you options to edit JVM parameters initially. Once you have instance up and running, it does give you an option to edit JVM configurations as well pass five application specific parameters but the name of parameters has to be PARAM1, PARAM2 ... May be this will be fixed in future versions or it's already available and I don't know. The latter is likely given that I did not spend a whole lot of time on it.  Anyway, here is screen shot of app running on Beanstalk.

Quick tip on hibernate batch operation

You can find the details of what batch operation with respect to DB is and related Hibernate guide at http://docs.jboss.org/hibernate/core/3.3/reference/en/html/batch.html . Any time you need to do bulk inserts/updates, it's better to do in batch to get a better performance. Recently I was developing a small app and followed Hibernate guide to make sure that my configurations were correct. Even after trying several things, I kept seeing following in log generated by Hibernate:

Hibernate: insert into Member (name, id) values (?, ?)
Hibernate: insert into Member (name, id) values (?, ?)
Hibernate: insert into Member (name, id) values (?, ?)
Hibernate: insert into Member (name, id) values (?, ?)
Hibernate: insert into Member (name, id) values (?, ?) 

But batch operation is supposed to generate statements like


insert into Member (name, id) values ('name0', 1),('name1', 2),('name2', 3),('name3', 4),('name4', 5),('name5', 6),('name6', 7),('name7', 8),('name8', 9),('name9', 10),('name10', 11),('name11', 12),('name12', 13),('name13', 14),('name14',
15),('name15', 16),('name16', 17),('name17', 18),('name18', 19),('name19', 20)

It turns out that even when batch operation is in progress, hibernate log shows individual operation. If you don't know this, you might be up for a ride figuring out what the heck is going on. The best way to make sure is to turn on the query logs in DB itself. For MySQL5 installed on Fedora, you do it by adding log parameter at /etc/my.conf

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
user=mysql
log=/var/log/mysqld.log


You should see statements like following at /var/log/mysqld.log :

2 Query insert into Member (name, id) values ('name0', 1),('name1', 2),('name2', 3),('name3', 4),('name4', 5),('name5', 6),('name6', 7),('name7', 8),('name8', 9),('name9', 10),('name10', 11),('name11', 12),('name12', 13),('name13', 14),('name14',
15),('name15', 16),('name16', 17),('name17', 18),('name18', 19),('name19', 20)
2 Query    commit

The complete test project is at http://anonsvn.jboss.org/repos/qa/prabhat/batch-insert . The relevant hibernate configuration is at http://anonsvn.jboss.org/repos/qa/prabhat/batch-insert/src/main/resources/hibernate.cfg.xml . If you are letting hibernate generate the primary key then don't use GenerationType.Identity in your  model otherwise batch insert will not take place.

New guide, tips and tricks for GateIn

Recently my team members published several how-to docs and guides on customizing GateIn Portal which applies to Enterprise Portal Platform (EPP) in most cases as well. Here is a compilation of those docs in one place:

• How to Create a New Portal on existing portal container with starter maven project: http://community.jboss.org/wiki/Createanewportalusingextension 
• How to Create a New Portal Container with starter maven project: http://community.jboss.org/wiki/Createanewportalcontainerusingextension
• How to customize landing page on login and logout based on user's role  http://community.jboss.org/wiki/Redirectausertopageonloginlogoutbasedonrole
• A community member took a different approach of creating a new portal without using extension : http://community.jboss.org/wiki/StepsToCreateANewPortalFromSample-Portal
• Send email to admin when a user registers or when there is x number of successive failed login attempts. See http://community.jboss.org/wiki/Sendingemailtoportaladministratorwhennewuserisregistered This is scheduled in next version of GateIn but you can try yourself by looking at https://issues.jboss.org/browse/GTNPORTAL-1805
• An example of Spring MVC Portlet. The complete guide is at guide and you can check out the maven project at http://anonsvn.jboss.org/repos/qa/people/mcupak/svn-browser as well.

The first two articles use extension mechanism which means that there is no or very very minimal change to OOB GateIn. I believe these docs should help you do an efficient customization of GateIn for your use.