copier-pydantic 0.1.4

Adds support for Pydantic Models in Copier templates

Copier Pydantic

Jinja2 extensions for Copier that enable using Pydantic Models for validation and within templates

Installation

With pip:

pip install copier-pydantic

With uv:

uv tool install copier --with copier-pydantic

With pipx:

pipx install copier
pipx inject copier copier-pydantic

Usage with Copier

In your copier template configuration:

# Add the jinja extensions
_jinja_extensions:
  - copier_pydantic.MultilineValidation
  - copier_pydantic.PydanticExtension

# and exclude the model.py file from your template
_exclude:
  - models.py
# or use the best practice of having the template in a sub directory
_subdirectory: template

So your template will look something like this

📁 template_root
├── 📄 models.py
├── 📄 copier.yml
└── 📁 template
    ├── 📄 {{_copier_conf.answers_file}}.jinja
    └── 📄 ...

With models.py containing your Pydantic BaseModel's like this

from pydantic import BaseModel

class DatabaseConfig(BaseModel):
    db_host: str
    db_port: int

you can then use your model to validate the question input like this

validated_example:
  type: yaml
  multiline: true
  default: |
    db_host: 'localhost'
    db_port: 5432
  validator: "{{ validated_example | validate_as(DatabaseConfig) }}"