Debugging Ruby Komodo IDE only
Tutorial
Komodo can debug Ruby programs locally or remotely. The instructions below describe how to configure Komodo and Ruby for debugging. For general information about using the Komodo debugger, see Komodo Debugger Functions.
Debugger commands can be accessed from the Debug menu, by shortcut keys, or from the Debug Toolbar. For a summary of debugger commands, see the Debugger Command List.
Configuring the Ruby Debugger
To specify which Ruby interpreter Komodo uses for debuging:
- Select Edit|Preferences (OS X: Komodo|Preferences).
- In the Preferences dialog box under Languages, click Ruby. Komodo searches for Ruby interpreters on your system and displays them in the drop-down list.
- If the preferred interpreter is in this list, click to select it. If not, click Browse to locate it.
- Click OK.
To start a local Ruby debugging session:
On the Debug menu or Debug Toolbar, click Go/Continue or Step In to invoke the debugging session. See Komodo Debugger Functions for full instructions on using Komodo's debugging functionality.
Note: Mac OS X users may have to install a more recent
version of Ruby (1.8.4 or greater). Linux users on x86_64 systems will need to
install a 64 bit version of the ruby-debug
library (see the Komodo FAQ entry for more
information).
Debugging Ruby Remotely
When debugging a Ruby program remotely, the program is executed on the remote system and the debug output is sent to Komodo. Komodo controls the debugging session (e.g. stepping and breakpoints) once the session starts on the remote system.
- Install the Ruby debugger application and associated files on the remote machine. All of these files are included in /lib/support/dbgp/rubylib beneath the Komodo installation directory (/Contents/SharedSupport/dbgp/rubylib on ac OS X). Copy rdbgp.rb and the contents of the DB directory to a convenient location on the remote machine. Note:Some of these files are shared library files (.so), which are platform specific. If your Komodo installation is on a different platform, download the Komodo-PythonRemoteDebugging package for the appropriate platform and Komodo version from the Komodo Remote Debugging page.
- Start Komodo on the local machine.
- On the remote machine, set the
dbgdir
variable to specify the location of the remote mahcine directory where you copied rdbgp.rb and its associated files.Windows
set dbgdir=<Path_To_rbdbgp.rb>
Linux/Mac OS X
dbgdir=<Path_To_rbdbgp.rb>
- On the remote machine, set the
RUBYDB_OPTS
variable his supplies the Ruby interpreter with the information that is necessary to connect to the Komodo application running on the local machine.Windows
set RUBYDB_OPTS=remoteport=<ServerName>:<Port> set RUBYOPT=
Linux/Mac OS X
export RUBYDB_OPTS=remoteport=<Server_Name>:<Port> unset RUBYOPT
- Start the debugger and open the program that you want to debug.
-
Windows
ruby -I%dbgdir% -r %dbgdir%\rdbgp.rb <Program_To_Debug.rb>
Linux/Mac OS X
ruby -I"$dbgdir" -r "$dbgdir"/rdbgp.rb <Program_To_Debug.rb>
The remote file will open in Komodo with the debugger stopped at the first line of executable code. A yellow arrow indicates the current position. You can now set breakpoints in this file, step through, and use other Komodo debugging features as if it were a local file. However, you cannot modify the file.
Note: For Komodo to open an editable copy of the file, a Mapped URI must be created to link the file on the remote filesystem with the URI Komodo receives from the remote debugger. |
Setting a Break in your Ruby Code
To break into a remote debugging session directly from within your Ruby code, insert the following:
ENV['RUBYDB_OPTS'] = 'remoteport=<Server_Name>:<Port>' $:.push('<Path_To_rdbgp.rb>') require 'rdbgp'
The first two lines set up the environment for remote debugging (similar to steps three and four above). The third line loads the debugger which breaks immediately by default.
Once the debugger has been loaded, subsequent breaks can be
specified in the program with the
Debugger.current_context.stop_next
function. It's a
good idea to wrap this function in a begin ... end
block in case the module wasn't loaded:
begin; Debugger.current_context.stop_next = 1; rescue Exception; end
These in-code breakpoints can be easily toggled by changing the boolean value (i.e. 1 = enabled, 0 = disabled).
Rubygems and RUBYOPT
Rubygems is the most commonly used framework for managing third-party Ruby modules.
Rubygems is included with the One-Click Installer (available
at http://rubyforge.org/projects/rubyinstaller/).
This installer adds the environment variable
RUBYOPT=rubygems
to the list of system variables.
This is usually correct behavior, as it automatically enables all
your Ruby scripts to use rubygems to find modules. However, it
will cause the Ruby debugger to always step into a file called
ubygems.rb
(a simple wrapper around
rubygems.rb
) when debugging.
There are three ways to avoid this:
- Set a breakpoint on the first line of the main file, and start the debugger with Go instead of the Step Into.
- In Komodo's Environment
preferences, set the
RUBYOPT
environment variable an empty string. - When you start the debugger, choose the
Environment tab in the Debugging Options
dialog box, add a new entry for
RUBYOPT
in the User Environment Variables box, and leave its value empty.
Debugging Rails Applications
Ruby on Rails applications can be debugged locally or remotely just like any other ruby application. However, since much of the Rails framework has to run within the debugger, the process is normally slower than with a standalone ruby program.
Local Rails Debugging
- Load the pertinent app or controllers files in Komodo.
- Set breakpoints in the methods where you want to stop.
- Load the script/server file that you would normally run from the command-line.
- In the Debugging Configuration dialog, set the Directory field to the top-level directory containing the apps folder.
- With the script/server file active, start the debugger.
Remote Rails Debugging
- Follow the steps described above in Debugging Ruby Remotely to install
the ruby debugger and set the environment variables
dbgdir
andRUBYDB_OPTS
. - Start the Rails script/server with the ruby
debugger from the top-level directory containing the
apps folder:
Windows
ruby -I%dbgdir% -r %dbgdir%\rdbgp.rb script/server
Linux/Mac OS X
ruby -I"$dbgdir" -r "$dbgdir"/rdbgp.rb script/server
The remote files will open in Komodo with the debugger stopped at the first line of executable code. A yellow arrow indicates the current position. You can now set breakpoints in this file, step through, and use other Komodo debugging features as if it were a local file. However, you cannot modify the file.