[Advanced] Adding a component to a project without yaml

Introduction

For some use cases, instantiating a component with Python rather than a component.yaml file is desirable. This guide assumes that you are already familiar with the basics of the Components system.

Creating a subdirectory

As with yaml-based components, you'll first need to create a new subdirectory in your components/ directory. This subdirectory will contain the component definition.

There, you'll create a component.py file to define your component instance. In this file, you will define a single @component-decorated function that instantiates the component type that you're interested in.

from dagster_components import ComponentLoadContext, component
from dagster_components.lib import DbtProjectComponent
from dagster_dbt import DagsterDbtTranslator, DbtCliResource


class MyTranslator(DagsterDbtTranslator): ...


@component
def my_dbt_component(context: ComponentLoadContext) -> DbtProjectComponent:
    return DbtProjectComponent(
        dbt=DbtCliResource(project_dir="."),
        translator=MyTranslator(),
    )

This function just needs to return an instance of your desired component type. In our case, we've used this functionality to customize the translator argument of the DbtProjectComponent class.