Pre-generation and Post-generation Hooks¶
You can define shell commands to run before and after structure generation using the pre_hooks and post_hooks keys in your YAML configuration. These are optional and allow you to automate setup or cleanup steps.
Hook Types¶
- pre_hooks: List of shell commands to run before generation. If any command fails (non-zero exit), generation is aborted.
- post_hooks: List of shell commands to run after generation completes. If any command fails, an error is shown.
Basic Example¶
pre_hooks:
- echo "Preparing environment..."
- ./scripts/prep.sh
post_hooks:
- echo "Generation complete!"
- ./scripts/cleanup.sh
files:
- README.md:
content: |
# My Project
How Hooks Work¶
Pre-hooks¶
- Execute in the order defined
- Run before any files or folders are created
- If any command returns non-zero exit code, generation stops
- Useful for environment preparation, validation, or dependency checks
Post-hooks¶
- Execute after all files and folders are created
- Run even if some file operations fail
- Errors are reported but don't stop execution
- Useful for cleanup, initialization, or notification tasks
Output Handling¶
- Output from hooks (stdout and stderr) is shown in the terminal
- Hook execution is logged with appropriate log levels
- Failed hooks display error messages with exit codes
Practical Examples¶
Environment Setup¶
pre_hooks:
- python -m venv .venv
- source .venv/bin/activate
- pip install --upgrade pip
post_hooks:
- source .venv/bin/activate
- pip install -r requirements.txt
- echo "Virtual environment ready!"
files:
- requirements.txt:
content: |
flask==2.3.0
requests==2.31.0
Git Repository Initialization¶
pre_hooks:
- git --version # Verify git is available
post_hooks:
- git init
- git add .
- git commit -m "Initial commit from STRUCT"
- echo "Git repository initialized"
files:
- .gitignore:
file: github://github/gitignore/main/Python.gitignore
- README.md:
content: |
# {{@ project_name @}}
Generated with STRUCT
Docker Setup¶
pre_hooks:
- docker --version
- echo "Setting up Docker environment..."
post_hooks:
- docker build -t {{@ project_name | slugify @}} .
- echo "Docker image built successfully"
files:
- Dockerfile:
content: |
FROM python:3.11-slim
WORKDIR /app
COPY . .
RUN pip install -r requirements.txt
CMD ["python", "app.py"]
- docker-compose.yml:
content: |
version: '3.8'
services:
app:
build: .
ports:
- "8000:8000"
Database Migration¶
pre_hooks:
- echo "Checking database connection..."
- pg_isready -h localhost -p 5432
post_hooks:
- python manage.py migrate
- python manage.py collectstatic --noinput
- echo "Database migrations complete"
files:
- manage.py:
content: |
#!/usr/bin/env python
import os
import sys
if __name__ == "__main__":
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "settings")
from django.core.management import execute_from_command_line
execute_from_command_line(sys.argv)
Testing and Validation¶
pre_hooks:
- echo "Validating prerequisites..."
- node --version
- npm --version
post_hooks:
- npm install
- npm run lint
- npm test
- echo "All tests passed!"
files:
- package.json:
content: |
{
"name": "{{@ project_name | slugify @}}",
"version": "1.0.0",
"scripts": {
"test": "jest",
"lint": "eslint src/"
}
}
Best Practices¶
- Keep hooks simple: Use external scripts for complex operations
- Handle errors gracefully: Check for tool availability in pre-hooks
- Use absolute paths: Hooks run in the target directory context
- Log important actions: Use echo statements for user feedback
- Test independently: Ensure hook commands work outside STRUCT
- Consider dependencies: Order hooks based on their requirements
Error Handling¶
Pre-hook Failures¶
pre_hooks:
- echo "Checking Python version..."
- python --version || (echo "Python not found!" && exit 1)
- echo "Python check passed"
Post-hook Error Tolerance¶
post_hooks:
- npm install || echo "Warning: npm install failed"
- git add . || echo "Warning: git add failed"
- echo "Setup complete (some warnings may have occurred)"
Variables in Hooks¶
You can use template variables in hook commands: