Wednesday, December 19, 2007

Javascript sleep() or wait() in Sahi

My previous post on 'Javascript sleep() or wait()' is visited a lot of times and I think I should write how the problem was eventually solved in Sahi.

Sahi needs to playback scripts written in javascript on the browser.
Let us consider a small example:

We are trying to automate an AJAXy mail client application which has an Inbox button, which when clicked, loads a part of the page, and this newly loaded content has a link 'Unread'.


When the first line is executed, the Inbox button gets clicked and the script has to wait till the relevant portions of the page load, before it can click 'Unread'.

To solve this, Sahi has a script parser which modifies this script to look something like this:

steps = new Array();
steps[steps.length] = "_click(_button('Inbox'));";
steps[steps.length] = "_click(_link('Unread'));";

And to execute these steps, it does:

var currentStep = 0;
function execute(){
if (currentStep == steps.length) return;
window.setTimeout('execute()', 1000);


Hope this helps people who are looking for a solution for javascript sleep.

Tuesday, December 11, 2007

java -cp does not work?

Was trying to get Sahi's batch and shell scripts to work properly since I get a lot of queries regarding database drivers not being found instpite of adding to the classpath.

The problem is this. I need to add a mysql driver to Sahi's classpath so that the scripts can access the driver to do some data driven testing.

So I had to add the mysql driver to this:

java -jar ../lib/sahi.jar

Trivially, I added a -cp option so the command looks like this:

java -cp ../extlib/mysql-connector-java-5.0.4-bin.jar -jar ../lib/sahi.jar

But this does NOT work. Why? Because an executable jar should have its classpath in its manifest file and not outside.

The way to solve this is to use:

java -cp ../extlib/mysql-connector-java-5.0.4-bin.jar;../lib/sahi.jar net.sf.sahi.Proxy

So I made these changes on my windows machine, and it worked. Then logged on to my newly installed ubuntu to check if the shell script works with the same changes.

Made the necessary semi-colon to colon conversion in the classpath, so it looks like this.

java -cp ../extlib/mysql-connector-java-5.0.4-bin.jar:../lib/sahi.jar net.sf.sahi.Proxy

The file has a few other lines too.

When I ran, it gave me a NoClassDefFound error for net/sf/sahi/Proxy! After hunting around quite a bit on the net to see if there was such a problem on linux, I realized that nobody on the forums seems to understand the problem even when somebody reported it.

Eventually I realized that since I had edited the file in windows, it was adding ^M characters at the newlines which was not being recognized by the shell. So I used another editor and got rid of them by deleting and reentering the newlines. (I could also have used dos2unix, but did not have it installed on my machine)

I also realized why the people in the forums did not understand the problem. Most of the replies were from people using linux all the time and the question posters would have mostly been using windows but since the problem was on a linux machine would have posted the question on linux forums!

Anyway, now things work properly :)