Write a pre-prompt hook

Write a pre-prompt hook#

A pre_prompt hook runs before the interactive prompts are shown to the user. Use it to check preconditions—for example, required system tools, network access, or minimum software versions. If the hook raises an exception or exits with a non-zero status, Cookieplone aborts cleanly before asking any questions.

Create the hook file#

Inside your template directory, create a hooks/ directory and add pre_prompt.py:

my-template/
└── templates/
    └── myproject/
        ├── cookieplone.json
        ├── hooks/
        │   └── pre_prompt.py
        └── {{cookiecutter.project_slug}}/
            └── ...

Check for a required tool#

# hooks/pre_prompt.py
import shutil
import sys


def check_git():
    if shutil.which("git") is None:
        print("ERROR: git is required but not found on PATH.")
        sys.exit(1)


if __name__ == "__main__":
    check_git()

Cookieplone executes this script as python hooks/pre_prompt.py. A non-zero exit code causes Cookieplone to abort and display the error output.

Check a minimum Python version#

# hooks/pre_prompt.py
import sys

MINIMUM_PYTHON = (3, 10)

if sys.version_info < MINIMUM_PYTHON:
    print(
        f"ERROR: Python {MINIMUM_PYTHON[0]}.{MINIMUM_PYTHON[1]} or later is required. "
        f"You are running {sys.version}."
    )
    sys.exit(1)

Raise a clean failure#

Calling sys.exit(1) produces a clean exit with a message. Do not raise unhandled exceptions; they produce a noisy traceback that obscures the real reason for the failure.

When pre_prompt hooks run#

The pre_prompt hook runs after the template repository is resolved and cloned, but before the interactive wizard starts. It does not receive the user's answers because none have been collected yet.

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