Remote Debugging for Python

Prerequisites

1. Install Visual Studio Code (VSCode)
   • Download VSCode
   • Install VSCode:

       sudo apt install ~/Downloads/code_1.45.1-1589445302_amd64.deb
     

   • Install the “Python” extension in VSCode
   • Install Python debugging package:

       pip install ptvsd
     

Configure Application for Debugging

1. Edit the Main Application File
   • Example configuration for app.py:

       import ptvsd
       # By default, remote debugging starts on port 5678
       ptvsd.enable_attach(address=('0.0.0.0', 5678), redirect_output=True)
       print("Now ready for the IDE to connect to the debugger")
       ptvsd.wait_for_attach()
     

Load the Code into Visual Studio Code

1. Transfer Code to Local Machine
   • Use Rsync via SSH:

       rsync -azP user@remote_host:/path/to/remote/code /path/to/local/code
     

Configure Visual Studio Code to Connect to the Remote Debugger

1. Start the Application with Debugging
   • Ensure your application starts with the debugging configuration:

       python app.py
     

2. Create launch.json in VSCode
   • Open the VSCode debug view and click on the gear icon to create a launch.json file.
   • Select “Remote Attach”.
   • Update the launch.json configuration:

       {
           "version": "0.2.0",
           "configurations": [
               {
                   "name": "Python: Remote Attach",
                   "type": "python",
                   "request": "attach",
                   "connect": {
                       "host": "remote_host",
                       "port": 5678
                   },
                   "pathMappings": [
                       {
                           "localRoot": "${workspaceFolder}",
                           "remoteRoot": "/path/to/remote/code"
                       }
                   ]
               }
           ]
       }
     

Generic Steps to Configure Remote Debugging for Any Python Application

1. Install Necessary Tools and Extensions
   • Ensure VSCode and the Python extension are installed.
   • Install ptvsd or debugpy in your Python environment.
2. Modify Application Code for Debugging
   • Add debugging configuration in your main application file (e.g., main.py or app.py):

       import debugpy
       debugpy.listen(("0.0.0.0", 5678))
       print("Waiting for debugger attach")
       debugpy.wait_for_client()
     

3. Transfer Code to Local Machine
   • Use tools like Rsync, SFTP, or any file synchronization tool to transfer code from the remote server to the local machine.
4. Configure VSCode for Remote Debugging
   • Create or update launch.json with appropriate settings:

       {
           "version": "0.2.0",
           "configurations": [
               {
                   "name": "Python: Remote Attach",
                   "type": "python",
                   "request": "attach",
                   "connect": {
                       "host": "remote_host",
                       "port": 5678
                   },
                   "pathMappings": [
                       {
                           "localRoot": "${workspaceFolder}",
                           "remoteRoot": "/path/to/remote/code"
                       }
                   ]
               }
           ]
       }
     

5. Start Application with Debugging Enabled
   • Run your Python application on the remote server with the debugging configuration:

       python app.py
     

6. Attach Debugger in VSCode
   • Open the debug view in VSCode and start the “Python: Remote Attach” configuration.

This guide provides a generic way to set up remote debugging for Python applications using VSCode.