Adding components to your project with Python

info

dg and Dagster Components are under active development. You may encounter feature gaps, and the APIs may change. To report issues or give feedback, please join the #dg-components channel in the Dagster Community Slack.

In some cases, you may want to add a component to your project with Python rather than YAML.

Prerequisites

Before adding a component with Python, you will need to either create a components-compatible project with dg or migrate an existing project to dg.

Additionally, to run the example below, you will need to clone the sample dbt project and delete the embedded git repository:

git clone --depth=1 https://github.com/dagster-io/jaffle-platform.git dbt && rm -rf dbt/.git

Then install the dbt project component:

uv

uv add dagster-dbt dbt-duckdb

pip

pip install dagster-dbt dbt-duckdb

Steps

To add a component with Python, you can use the dg scaffold command with the --format python option. For example, to scaffold the dbt project component, you can run the following:

dg scaffold dagster_dbt.DbtProjectComponent jdbt --project-path dbt/jdbt --format python

Running this command will generate a component.py file, rather than a component.yaml file:

cd src/hello_world && tree

.
├── __init__.py
├── __pycache__
│   └── __init__.cpython-312.pyc
├── definitions.py
├── defs
│   ├── __init__.py
│   └── jdbt
│       └── component.py
└── lib
    └── __init__.py