How to Solve Error: subprocess-exited-with-error

The subprocess-exited-with-error error occurs when a Python subprocess fails during execution, often in scenarios like package installation, running shell commands, or executing Python scripts. This can arise in various contexts, such as pip or setuptools. Here’s a step-by-step approach to solve it:


1. Understand the Context of the Error

  • When does the error occur? For example, during pip install, a build process, or executing a specific script.
  • What is the error message? Look for details in the traceback, as it often points to the exact issue.

2. Troubleshooting by Scenario

A. During Package Installation with pip

  1. Inspect the Error Message
    • Look for logs mentioning missing dependencies, permissions, or build failures.
  2. Common Fixes
    • Update pip, setuptools, and wheel:
      python -m pip install --upgrade pip setuptools wheel
      
    • Install system dependencies: Some packages require external libraries (e.g., libffi-dev, python3-dev for Linux).
      • On Ubuntu:
        sudo apt-get install build-essential libssl-dev
        
      • On macOS:
        brew install openssl
        
  3. Use Precompiled Wheels If a package fails to build:
    pip install <package-name> --only-binary=:all:
    

B. During Custom Script Execution

  1. Check Your Script
    • Confirm that the script runs correctly when executed manually.
    • Review file paths and arguments passed to subprocess commands.
  2. Debug Subprocess Commands
    • Use check=True in subprocess.run to get clearer error messages:
      import subprocess
      result = subprocess.run(['command', 'arg1', 'arg2'], check=True)
      
    • Redirect output to a file for detailed logs:
      result = subprocess.run(['command', 'arg1'], stdout=open('out.log', 'w'), stderr=subprocess.STDOUT)
      

C. In a CI/CD Pipeline

  • Ensure all required dependencies are installed before executing the task.
  • Add verbose logging to see detailed output.
    pip install <package-name> --verbose
    

3. Common Underlying Causes

  1. Incorrect Python Version
    • Some packages require specific Python versions. Check compatibility on PyPI.
    python --version
    
  2. Missing Permissions
    • Use sudo for installation or adjust permissions.
      sudo pip install <package-name>
      
  3. Virtual Environment Issues
    • Activate the correct virtual environment.
      source venv/bin/activate
      
  4. Network or Proxy Issues
    • If you’re behind a proxy:
      pip install <package-name> --proxy http://proxy-address:port
      

4. Check Online Resources

  • Review GitHub issues for the package or library.
  • Check Stack Overflow or the Python community for similar issues.

5. Example

If the error occurs during pip install numpy, the output might include:

error: subprocess-exited-with-error
...
Failed to build numpy

Solution:

  1. Upgrade tools:
    python -m pip install --upgrade pip setuptools wheel
    
  2. Install the required system dependencies:
    sudo apt-get install build-essential libatlas-base-dev
    

If you share your specific scenario and error details, get in touch with our experts at hire tech firms and they will be happy to answer you!