Debugging Django Applications in Docker with WSL2 Using PyCharm Gateway

Problem

1. JetBrains Gateway often shows the PyCharm project as "running," but the IDE window fails to open.
2. Confusion arises from having two separate PyCharm setups (Windows and Gateway-based), leading to differences in configurations and external tools.
3. Debugging via Attach to DAP (with debugpy) is inconsistent. Breakpoints are not hit, and an error indicates mismatched file paths.
4. Lack of clarity around the recommended debugging configuration approach (Attach to DAP, Python Debug Server, or Docker Compose Run/Debug).
5. Issues with Dev Containers in PyCharm when Docker Engine runs natively in WSL2 as opposed to Docker Desktop.

Cause

1. Gateway-launched IDE uses a separate backend and settings store, explaining discrepancies with the locally launched PyCharm on Windows.
2. The inconsistent breakpoint hitting issue is often associated with incorrect path mappings between the container and the PyCharm backend.
3. Dev Containers plugin in PyCharm relies on Docker Desktop's named pipe, creating incompatibility with environments where Docker Engine is directly installed in WSL2.
4. Debugpy support in PyCharm is not yet fully mature under certain complex setups.

Resolution

1. Use a Gateway + WSL approach with the latest PyCharm version for stable debugging.
2. Configure a Docker Compose interpreter in PyCharm and use the recently-improved debugpy functionality (introduced in PyCharm 2026.1).
3. For debugging:
   • Create a Python Attach to DAP Run/Debug configuration with the following settings:
     • Remote address: 0.0.0.0:5678
     • Local project path: e.g., /home/ianf/GitHub/CourtesyCreditRequest
     • Remote project path: e.g., /code
   • Start the application using docker compose -f docker-compose.yml -f docker-compose.debug.yml up -d --build, then attach to the process using the configuration above.
4. To prevent path mapping issues, ensure paths are accurately configured between the host file system and the container’s file system.
5. Avoid using Dev Containers in this setup as they are currently limited to Docker Desktop dependency.
6. When Gateway behaves inconsistently (e.g., IDE not opening or backend showing as "running"), manually clean caches and JetBrains-specific artifacts to reset:
   • Remove files from %LOCALAPPDATA%\JetBrains\JetBrainsClient* on Windows and/or ~/.cache/JetBrains within WSL.
   • Logs can be collected via Help | Collect Logs and Diagnostic Data for debugging further with JetBrains support.
7. If JetBrains Gateway proves too unreliable, consider alternative workflows or editors, like Visual Studio Code with its Dev Containers extension, which streamlines Docker-based development and debugging.

For the most consistent experience, keep PyCharm and Gateway updated to the latest versions as incremental improvements are frequently introduced.