singer_sdk.schema.source.SchemaSource

class singer_sdk.schema.source.SchemaSource

Abstract base class for schema sources.

__init__()

Initialize the schema source with caching.

Return type:

None

abstractmethod fetch_schema(key)

Retrieve a JSON schema from this source.

Parameters:

key (_TKey) – The schema component name to retrieve.

Returns:

A JSON schema dictionary.

Raises:

• ValueError – If the component is not found or invalid.

• requests.RequestException – If fetching schema from URL fails.

Return type:

dict[str, Any]

final get_schema(key, /, *, key_properties=())

Convenience method to get a schema component.

Parameters:

• key (_TKey) – The schema component name to retrieve.

• key_properties (Sequence[str]) – The stream’s key properties.

Returns:

A JSON schema dictionary.

Raises:

• SchemaNotFoundError – If the schema is not found or cannot be fetched.

• SchemaNotValidError – If the schema is not a JSON object.

Return type:

Schema

final preprocess_schema(schema, *, key_properties=())

Pre-process the schema before providing it to the stream.

Parameters:

• schema (Schema) – A JSON schema.

• key_properties (Sequence[str]) – The stream’s key properties.

Returns:

The pre-processed schema.

Return type:

Schema