airbyte/docs/platform/connector-development/config-based/advanced-topics/custom-components.md

Custom Components

:::info Please help us improve the low code CDK! If you find yourself needing to build a custom component,please create a feature request issue. If appropriate, we'll add it directly to the framework (or you can submit a PR)!

If an issue already exist for the missing feature you need, please upvote or comment on it so we can prioritize the issue accordingly. :::

Any built-in components can be overloaded by a custom Python class. To create a custom component, define a new class in a new file in the connector's module. The class must implement the interface of the component it is replacing. For instance, a pagination strategy must implement airbyte_cdk.sources.declarative.requesters.paginators.strategies.pagination_strategy.PaginationStrategy. The class must also be a dataclass where each field represents an argument to configure from the yaml file, and an InitVar named parameters.

For example:

@dataclass
class MyPaginationStrategy(PaginationStrategy):
  my_field: Union[InterpolatedString, str]
  parameters: InitVar[Mapping[str, Any]]

  def __post_init__(self, parameters: Mapping[str, Any]):
    pass

  def next_page_token(self, response: requests.Response, last_records: List[Mapping[str, Any]]) -> Optional[Any]:
    pass

  def reset(self):
    pass

This class can then be referred from the yaml file by specifying the type of custom component and using its fully qualified class name:

pagination_strategy:
  type: "CustomPaginationStrategy"
  class_name: "my_connector_module.MyPaginationStrategy"
  my_field: "hello world"

Custom Components that pass fields to child components

There are certain scenarios where a child subcomponent might rely on a field defined on a parent component. For regular components, we perform this propagation of fields from the parent component to the child automatically. However, custom components do not support this behavior. If you have a child subcomponent of your custom component that falls under this use case, you will see an error message like:

Error creating component 'DefaultPaginator' with parent custom component source_example.components.CustomRetriever: Please provide DefaultPaginator.$parameters.url_base

When you receive this error, you can address this by defining the missing field within the $parameters block of the child component.

  paginator:
    type: "DefaultPaginator"
    <...>
    $parameters:
      url_base: "https://example.com"