Debugging Google AppEngine with PyDev in Eclipse

This assumes you have Google AppEngine, Eclipse & PyDev installed.

I’m gonna have to go back a bit on what I said about creating a python project in this previous post. Instead of creating individual projects for each app you intend to create, I found it much easier to create one project that encompassed my entire development directory. Also, I received a few emails on how I was adding PyAMF and the google sdk to get code completion support. > Prefs

I added the .egg file for PyAMF and I zipped up the google folder underneath my appengine installation and added it.

 

Now onto debugging.

1. Create a new PyDev Project. Right click the project folder and Add New Folder. Click Advanced, Check the Link to folder and point it to the your appengine installation directory. Essentially your entire AppEngine Directory.

 

My project now looks like this

 

2. Now I open the project I want to debug and place my breakpoints.

 

3. Now right click on the dev_appserver.py file  and go to Debug As > Open Debug Dialog. 

Right Click Python Run and choose New. 

Name the configuration

Select your Project

Add the dev_appserver.py as the Main Module

 

Then switch to the Arguments tab and enter the project you want to debug for the program arguments. You can also enter the —port=8080 switch here just like the command prompt.

 

Finally, Click Apply Then debug. You should see the following the Console:

 

Run your  app. From Flex or from the Browser you should be able to hit your break points. Oh and I don’t recommend doing this to your arm or back. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Tags: PyDev, python, eclipse, debugging, AppEngine, PyAMF

Comments

[Thijs Triemstra]

Thanks for the tutorial Brian, very useful :)

[jeremy]

Good thing you stopped me with that last 'step'. I just canceled my tat appointment.

Thanks.

[Brian Holmes]

@Jeremy,
That'll happen.

[Nelson Silva]

Hi,

I've been debugging my google appengine app with PyDev. I added the google_engine dir to my PYTHONPATH, setup the main module as ${google_appengine}\dev_appserver.py, then the arguments:

Base directory : ${workspace_loc}

Arguments: ${project_name}

This way I have a project per application and I don't have to include the SDK's source.

Hope this is helpful.

Regards,

Nelson Silva

[Brian Holmes]

@Nelson,
Thanks for the tip. You're right that's much better.

[RobT]

You rock. Thanks!

[Josue]

I couldn't make like Nelson suggested. In Debug Dialog when setting "${google_appengine}\dev_appserver.py" to the Main Module field I got a "Unable to resolve location". How did you workaround?

Thanks in advance.