feat: add CustomSchemaNormalization (#194)

Signed-off-by: Artem Inzhyyants <artem.inzhyyants@gmail.com>

airbyte_cdk/sources/declarative/declarative_component_schema.yaml

@@ -667,6 +667,28 @@ definitions:
       $parameters:
         type: object
         additionalProperties: true
+  CustomSchemaNormalization:
+    title: Custom Schema Normalization
+    description: Schema normalization component whose behavior is derived from a custom code implementation of the connector.
+    type: object
+    additionalProperties: true
+    required:
+      - type
+      - class_name
+    properties:
+      type:
+        type: string
+        enum: [ CustomSchemaNormalization ]
+      class_name:
+        title: Class Name
+        description: Fully-qualified name of the class that will be implementing the custom normalization. The format is `source_<name>.<package>.<class_name>`.
+        type: string
+        additionalProperties: true
+        examples:
+          - "source_amazon_seller_partner.components.LedgerDetailedViewReportsTypeTransformer"
+      $parameters:
+        type: object
+        additionalProperties: true
   CustomStateMigration:
     title: Custom State Migration
     description: Apply a custom transformation on the input state.
@@ -2600,7 +2622,11 @@ definitions:
           - "$ref": "#/definitions/CustomRecordFilter"
           - "$ref": "#/definitions/RecordFilter"
       schema_normalization:
-        "$ref": "#/definitions/SchemaNormalization"
+        title: Schema Normalization
+        description: Responsible for normalization according to the schema.
+        anyOf:
+          - "$ref": "#/definitions/SchemaNormalization"
+          - "$ref": "#/definitions/CustomSchemaNormalization"
         default: None
       $parameters:
         type: object

airbyte_cdk/sources/declarative/extractors/__init__.py

@@ -9,8 +9,10 @@
 from airbyte_cdk.sources.declarative.extractors.response_to_file_extractor import (
     ResponseToFileExtractor,
 )
+from airbyte_cdk.sources.declarative.extractors.type_transformer import TypeTransformer
 
 __all__ = [
+    "TypeTransformer",
     "HttpSelector",
     "DpathExtractor",
     "RecordFilter",

airbyte_cdk/sources/declarative/extractors/record_selector.py

@@ -10,16 +10,14 @@
 from airbyte_cdk.sources.declarative.extractors.http_selector import HttpSelector
 from airbyte_cdk.sources.declarative.extractors.record_extractor import RecordExtractor
 from airbyte_cdk.sources.declarative.extractors.record_filter import RecordFilter
+from airbyte_cdk.sources.declarative.extractors.type_transformer import (
+    TypeTransformer as DeclarativeTypeTransformer,
+)
 from airbyte_cdk.sources.declarative.interpolation import InterpolatedString
 from airbyte_cdk.sources.declarative.models import SchemaNormalization
 from airbyte_cdk.sources.declarative.transformations import RecordTransformation
 from airbyte_cdk.sources.types import Config, Record, StreamSlice, StreamState
-from airbyte_cdk.sources.utils.transform import TransformConfig, TypeTransformer
-
-SCHEMA_TRANSFORMER_TYPE_MAPPING = {
-    SchemaNormalization.None_: TransformConfig.NoTransform,
-    SchemaNormalization.Default: TransformConfig.DefaultSchemaNormalization,
-}
+from airbyte_cdk.sources.utils.transform import TypeTransformer
 
 
 @dataclass
@@ -38,7 +36,7 @@ class RecordSelector(HttpSelector):
     extractor: RecordExtractor
     config: Config
     parameters: InitVar[Mapping[str, Any]]
-    schema_normalization: TypeTransformer
+    schema_normalization: Union[TypeTransformer, DeclarativeTypeTransformer]
     name: str
     _name: Union[InterpolatedString, str] = field(init=False, repr=False, default="")
     record_filter: Optional[RecordFilter] = None

airbyte_cdk/sources/declarative/extractors/type_transformer.py

@@ -0,0 +1,55 @@
+#
+# Copyright (c) 2025 Airbyte, Inc., all rights reserved.
+#
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass
+from typing import Any, Dict, Mapping
+
+
+@dataclass
+class TypeTransformer(ABC):
+    """
+    Abstract base class for implementing type transformation logic.
+
+    This class provides a blueprint for defining custom transformations
+    on data records based on a provided schema. Implementing classes
+    must override the `transform` method to specify the transformation
+    logic.
+
+    Attributes:
+        None explicitly defined, as this is a dataclass intended to be
+        subclassed.
+
+    Methods:
+        transform(record: Dict[str, Any], schema: Mapping[str, Any]) -> None:
+            Abstract method that must be implemented by subclasses.
+            It performs a transformation on a given data record based
+            on the provided schema.
+
+    Usage:
+        To use this class, create a subclass that implements the
+        `transform` method with the desired transformation logic.
+    """
+
+    @abstractmethod
+    def transform(
+        self,
+        record: Dict[str, Any],
+        schema: Mapping[str, Any],
+    ) -> None:
+        """
+        Perform a transformation on a data record based on a given schema.
+
+        Args:
+            record (Dict[str, Any]): The data record to be transformed.
+            schema (Mapping[str, Any]): The schema that dictates how
+                the record should be transformed.
+
+        Returns:
+            None
+
+        Raises:
+            NotImplementedError: If the method is not implemented
+                by a subclass.
+        """

airbyte_cdk/sources/declarative/models/declarative_component_schema.py

@@ -268,6 +268,22 @@ class Config:
     parameters: Optional[Dict[str, Any]] = Field(None, alias="$parameters")
 
 
+class CustomSchemaNormalization(BaseModel):
+    class Config:
+        extra = Extra.allow
+
+    type: Literal["CustomSchemaNormalization"]
+    class_name: str = Field(
+        ...,
+        description="Fully-qualified name of the class that will be implementing the custom normalization. The format is `source_<name>.<package>.<class_name>`.",
+        examples=[
+            "source_amazon_seller_partner.components.LedgerDetailedViewReportsTypeTransformer"
+        ],
+        title="Class Name",
+    )
+    parameters: Optional[Dict[str, Any]] = Field(None, alias="$parameters")
+
+
 class CustomStateMigration(BaseModel):
     class Config:
         extra = Extra.allow
@@ -1530,7 +1546,11 @@ class RecordSelector(BaseModel):
         description="Responsible for filtering records to be emitted by the Source.",
         title="Record Filter",
     )
-    schema_normalization: Optional[SchemaNormalization] = SchemaNormalization.None_
+    schema_normalization: Optional[Union[SchemaNormalization, CustomSchemaNormalization]] = Field(
+        SchemaNormalization.None_,
+        description="Responsible for normalization according to the schema.",
+        title="Schema Normalization",
+    )
     parameters: Optional[Dict[str, Any]] = Field(None, alias="$parameters")
 
 

airbyte_cdk/sources/declarative/parsers/model_to_component_factory.py

@@ -82,9 +82,6 @@
 from airbyte_cdk.sources.declarative.extractors.record_filter import (
     ClientSideIncrementalRecordFilterDecorator,
 )
-from airbyte_cdk.sources.declarative.extractors.record_selector import (
-    SCHEMA_TRANSFORMER_TYPE_MAPPING,
-)
 from airbyte_cdk.sources.declarative.incremental import (
     ChildPartitionResumableFullRefreshCursor,
     CursorFactory,
@@ -100,7 +97,9 @@
 from airbyte_cdk.sources.declarative.migrations.legacy_to_per_partition_state_migration import (
     LegacyToPerPartitionStateMigration,
 )
-from airbyte_cdk.sources.declarative.models import CustomStateMigration
+from airbyte_cdk.sources.declarative.models import (
+    CustomStateMigration,
+)
 from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
     AddedFieldDefinition as AddedFieldDefinitionModel,
 )
@@ -185,6 +184,9 @@
 from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
     CustomSchemaLoader as CustomSchemaLoader,
 )
+from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
+    CustomSchemaNormalization as CustomSchemaNormalizationModel,
+)
 from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
     CustomTransformation as CustomTransformationModel,
 )
@@ -311,6 +313,9 @@
 from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
     ResponseToFileExtractor as ResponseToFileExtractorModel,
 )
+from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
+    SchemaNormalization as SchemaNormalizationModel,
+)
 from airbyte_cdk.sources.declarative.models.declarative_component_schema import (
     SchemaTypeIdentifier as SchemaTypeIdentifierModel,
 )
@@ -445,6 +450,11 @@
 
 ComponentDefinition = Mapping[str, Any]
 
+SCHEMA_TRANSFORMER_TYPE_MAPPING = {
+    SchemaNormalizationModel.None_: TransformConfig.NoTransform,
+    SchemaNormalizationModel.Default: TransformConfig.DefaultSchemaNormalization,
+}
+
 
 class ModelToComponentFactory:
     EPOCH_DATETIME_FORMAT = "%s"
@@ -493,6 +503,7 @@ def _init_mappings(self) -> None:
             CustomRequesterModel: self.create_custom_component,
             CustomRetrieverModel: self.create_custom_component,
             CustomSchemaLoader: self.create_custom_component,
+            CustomSchemaNormalizationModel: self.create_custom_component,
             CustomStateMigration: self.create_custom_component,
             CustomPaginationStrategyModel: self.create_custom_component,
             CustomPartitionRouterModel: self.create_custom_component,
@@ -2000,7 +2011,6 @@ def create_record_selector(
         client_side_incremental_sync: Dict[str, Any] | None = None,
         **kwargs: Any,
     ) -> RecordSelector:
-        assert model.schema_normalization is not None  # for mypy
         extractor = self._create_component_from_model(
             model=model.extractor, decoder=decoder, config=config
         )
@@ -2018,8 +2028,10 @@ def create_record_selector(
                 else None,
                 **client_side_incremental_sync,
             )
-        schema_normalization = TypeTransformer(
-            SCHEMA_TRANSFORMER_TYPE_MAPPING[model.schema_normalization]
+        schema_normalization = (
+            TypeTransformer(SCHEMA_TRANSFORMER_TYPE_MAPPING[model.schema_normalization])
+            if isinstance(model.schema_normalization, SchemaNormalizationModel)
+            else self._create_component_from_model(model.schema_normalization, config=config)  # type: ignore[arg-type] # custom normalization model expected here
         )
 
         return RecordSelector(