Add deprecated decorators for dataclass output (#3044)

* Add deprecated decorators for dataclass output

* Fix deprecated dataclass metadata handling

* Fix deprecated import for existing decorators

* Add E2E coverage for deprecated dataclass decorators

Author: koxudaxi

src/datamodel_code_generator/model/base.py

@@ -741,6 +741,15 @@ def create_reuse_model(self, base_ref: Reference) -> Self:
             treat_dot_as_module=self._treat_dot_as_module,
         )
 
+    def _set_deprecated_decorator(self) -> None:
+        """Add a class-level deprecated decorator when schema metadata requires it."""
+        if not self.extra_template_data.get("deprecated"):
+            return
+        if not any(decorator.startswith("@deprecated") for decorator in self.decorators):
+            message = f"{self.class_name} is deprecated."
+            self.decorators = [*self.decorators, f"@deprecated({message!r})"]
+        self._additional_imports.append(Import.from_full_path("typing_extensions.deprecated"))
+
     def replace_children_in_models(self, models: list[DataModel], new_ref: Reference) -> None:
         """Replace reference children if their parent model is in models list."""
         from datamodel_code_generator.parser.base import get_most_of_parent  # noqa: PLC0415

src/datamodel_code_generator/model/dataclass.py

@@ -97,6 +97,7 @@ def __init__(  # noqa: PLR0913
                 self.dataclass_arguments["frozen"] = True
             if keyword_only:
                 self.dataclass_arguments["kw_only"] = True
+        self._set_deprecated_decorator()
 
     def create_reuse_model(self, base_ref: Reference) -> DataClass:
         """Create inherited model with empty fields pointing to base reference."""

src/datamodel_code_generator/model/pydantic_v2/dataclass.py

@@ -95,6 +95,7 @@ def __init__(  # noqa: PLR0913
                 self.dataclass_arguments["frozen"] = True
             if keyword_only:
                 self.dataclass_arguments["kw_only"] = True
+        self._set_deprecated_decorator()
 
         config_parameters: dict[str, Any] = {}
 

src/datamodel_code_generator/parser/jsonschema.py

@@ -1139,6 +1139,7 @@ def _create_variant_model(  # noqa: PLR0913, PLR0917
         unique_name = self.model_resolver.get_class_name(variant_name, unique=True).name
         model_path = [*path[:-1], unique_name]
         reference = self.model_resolver.add(model_path, unique_name, class_name=True, unique=False, loaded=True)
+        self._set_schema_metadata(reference.path, obj)
         self.set_schema_extensions(reference.path, obj)
         model = self._create_data_model(
             model_type=data_model_type_class,
@@ -1427,6 +1428,12 @@ def _set_schema_metadata(self, path: str, obj: JsonSchemaObject) -> None:
         self.set_schema_id(path, obj)
         self.set_additional_properties(path, obj)
         self.set_unevaluated_properties(path, obj)
+        self.set_deprecated(path, obj)
+
+    def set_deprecated(self, path: str, obj: JsonSchemaObject) -> None:
+        """Set deprecated flag in extra template data."""
+        if obj.extras.get("deprecated") is True:
+            self.extra_template_data[path]["deprecated"] = True
 
     def set_schema_extensions(self, path: str, obj: JsonSchemaObject) -> None:
         """Set schema extensions (x-* fields) in extra template data."""
@@ -2492,9 +2499,7 @@ def _parse_object_common_part(  # noqa: PLR0912, PLR0913, PLR0915
                     )
         name = self._apply_title_as_name(name, obj)  # pragma: no cover
         reference = self.model_resolver.add(path, name, class_name=True, loaded=True)
-        self.set_additional_properties(reference.path, obj)
-        self.set_unevaluated_properties(reference.path, obj)
-        self.set_schema_id(reference.path, obj)
+        self._set_schema_metadata(reference.path, obj)
         self.set_schema_extensions(reference.path, obj)
 
         generates_separate = self._should_generate_separate_models(fields, base_classes)
@@ -2657,6 +2662,7 @@ def parse_all_of(
                 existing_ref = self.model_resolver.references.get(full_path)
                 if existing_ref is not None and not existing_ref.loaded:
                     reference = self.model_resolver.add(path, name, class_name=True, loaded=True)
+                    self._set_schema_metadata(reference.path, obj)
                     self.set_schema_extensions(reference.path, obj)
                     field = self.data_model_field_type(
                         name=None,
@@ -2711,6 +2717,7 @@ def parse_all_of(
                 required=required,
             )
         reference = self.model_resolver.add(path, name, class_name=True, loaded=True)
+        self._set_schema_metadata(reference.path, obj)
         self.set_schema_extensions(reference.path, obj)
         all_of_data_type = self._parse_object_common_part(
             name,
@@ -2906,8 +2913,7 @@ def parse_object(
             )
             data_model_type_class = self.data_model_root_type
 
-        self.set_additional_properties(reference.path, obj)
-        self.set_unevaluated_properties(reference.path, obj)
+        self._set_schema_metadata(reference.path, obj)
         self.set_schema_extensions(reference.path, obj)
 
         generates_separate = self._should_generate_separate_models(fields, None)
@@ -3368,6 +3374,7 @@ def parse_array(
         """Parse array schema into a root model with array type."""
         name = self._apply_title_as_name(name, obj)
         reference = self.model_resolver.add(path, name, loaded=True, class_name=True)
+        self._set_schema_metadata(reference.path, obj)
         self.set_schema_extensions(reference.path, obj)
         field = self.parse_array_fields(original_name or name, obj, [*path, name])
 
@@ -3613,7 +3620,7 @@ def _get_field_name_from_dict_enum(cls, enum_part: dict[str, Any], index: int) -
             return str(enum_part["const"])
         return f"value_{index}"
 
-    def parse_enum(
+    def parse_enum(  # noqa: PLR0915
         self,
         name: str,
         obj: JsonSchemaObject,
@@ -3690,6 +3697,7 @@ def parse_enum(
                 loaded=True,
                 model_type="enum",
             )
+            self._set_schema_metadata(reference.path, obj)
             self.set_schema_extensions(reference.path, obj)
             data_model_root_type = self.data_model_root_type(
                 reference=reference,
@@ -3761,11 +3769,12 @@ def create_enum(reference_: Reference) -> DataType:
             loaded=True,
             model_type="enum",
         )
+        self._set_schema_metadata(reference.path, obj)
+        self.set_schema_extensions(reference.path, obj)
 
         if not nullable:
             return create_enum(reference)
 
-        self.set_schema_extensions(reference.path, obj)
         enum_reference = self.model_resolver.add(
             [*path, "Enum"],
             f"{reference.name}Enum",

tests/data/expected/main/jsonschema/deprecated_dataclass.py

@@ -0,0 +1,16 @@
+# generated by datamodel-codegen:
+#   filename:  deprecated_dataclass.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from typing_extensions import deprecated
+
+
+@deprecated('LegacyUser is deprecated.')
+@dataclass
+class LegacyUser:
+    name: str
+    email: str | None = None

tests/data/expected/main/jsonschema/deprecated_dataclass_with_other_decorator.py

@@ -0,0 +1,18 @@
+# generated by datamodel-codegen:
+#   filename:  deprecated_dataclass.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from some_module import some_decorator
+from typing_extensions import deprecated
+
+
+@some_decorator
+@deprecated('LegacyUser is deprecated.')
+@dataclass
+class LegacyUser:
+    name: str
+    email: str | None = None

tests/data/expected/main/jsonschema/deprecated_pydantic_v2_dataclass.py

@@ -0,0 +1,15 @@
+# generated by datamodel-codegen:
+#   filename:  deprecated_dataclass.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from pydantic.dataclasses import dataclass
+from typing_extensions import deprecated
+
+
+@deprecated('LegacyUser is deprecated.')
+@dataclass
+class LegacyUser:
+    name: str
+    email: str | None = None

tests/data/expected/main/jsonschema/deprecated_pydantic_v2_dataclass_with_other_decorator.py

@@ -0,0 +1,17 @@
+# generated by datamodel-codegen:
+#   filename:  deprecated_dataclass.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from pydantic.dataclasses import dataclass
+from some_module import some_decorator
+from typing_extensions import deprecated
+
+
+@some_decorator
+@deprecated('LegacyUser is deprecated.')
+@dataclass
+class LegacyUser:
+    name: str
+    email: str | None = None

tests/data/jsonschema/deprecated_dataclass.json

@@ -0,0 +1,15 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "LegacyUser",
+  "type": "object",
+  "deprecated": true,
+  "properties": {
+    "name": {
+      "type": "string"
+    },
+    "email": {
+      "type": "string"
+    }
+  },
+  "required": ["name"]
+}

tests/main/jsonschema/test_main_jsonschema.py

@@ -3963,6 +3963,85 @@ def test_main_dataclass_field(output_file: Path) -> None:
     )
 
 
+def test_main_dataclass_deprecated_model(output_file: Path) -> None:
+    """Test dataclass generation with deprecated schema metadata."""
+    run_main_and_assert(
+        input_path=JSON_SCHEMA_DATA_PATH / "deprecated_dataclass.json",
+        output_path=output_file,
+        input_file_type="jsonschema",
+        assert_func=assert_file_content,
+        expected_file="deprecated_dataclass.py",
+        extra_args=["--output-model-type", "dataclasses.dataclass"],
+    )
+
+
+def test_main_dataclass_deprecated_model_preserves_existing_decorator(output_file: Path) -> None:
+    """Test deprecated dataclass generation keeps the import with an existing decorator."""
+    run_main_and_assert(
+        input_path=JSON_SCHEMA_DATA_PATH / "deprecated_dataclass.json",
+        output_path=output_file,
+        input_file_type="jsonschema",
+        assert_func=assert_file_content,
+        expected_file="deprecated_dataclass.py",
+        extra_args=[
+            "--output-model-type",
+            "dataclasses.dataclass",
+            "--class-decorators",
+            "@deprecated('LegacyUser is deprecated.')",
+        ],
+    )
+
+
+def test_main_dataclass_deprecated_model_with_other_decorator(output_file: Path) -> None:
+    """Test deprecated dataclass generation adds deprecation alongside other decorators."""
+    run_main_and_assert(
+        input_path=JSON_SCHEMA_DATA_PATH / "deprecated_dataclass.json",
+        output_path=output_file,
+        input_file_type="jsonschema",
+        assert_func=assert_file_content,
+        expected_file="deprecated_dataclass_with_other_decorator.py",
+        extra_args=[
+            "--output-model-type",
+            "dataclasses.dataclass",
+            "--class-decorators",
+            "@some_decorator",
+            "--additional-imports",
+            "some_module.some_decorator",
+        ],
+    )
+
+
+def test_main_pydantic_v2_dataclass_deprecated_model(output_file: Path) -> None:
+    """Test pydantic v2 dataclass generation with deprecated schema metadata."""
+    run_main_and_assert(
+        input_path=JSON_SCHEMA_DATA_PATH / "deprecated_dataclass.json",
+        output_path=output_file,
+        input_file_type="jsonschema",
+        assert_func=assert_file_content,
+        expected_file="deprecated_pydantic_v2_dataclass.py",
+        extra_args=["--output-model-type", "pydantic_v2.dataclass"],
+    )
+
+
+def test_main_pydantic_v2_dataclass_deprecated_model_with_other_decorator(output_file: Path) -> None:
+    """Test pydantic v2 dataclass generation adds deprecation alongside other decorators."""
+    run_main_and_assert(
+        input_path=JSON_SCHEMA_DATA_PATH / "deprecated_dataclass.json",
+        output_path=output_file,
+        input_file_type="jsonschema",
+        assert_func=assert_file_content,
+        expected_file="deprecated_pydantic_v2_dataclass_with_other_decorator.py",
+        extra_args=[
+            "--output-model-type",
+            "pydantic_v2.dataclass",
+            "--class-decorators",
+            "@some_decorator",
+            "--additional-imports",
+            "some_module.some_decorator",
+        ],
+    )
+
+
 @pytest.mark.skipif(
     not is_supported_in_black(PythonVersion.PY_312),
     reason="Black does not support Python 3.12",