Merge 999642079d into eca80ff663

python/packages/autogen-core/src/autogen_core/utils/__init__.py

@@ -0,0 +1,3 @@
+from ._json_to_pydantic import schema_to_pydantic_model
+
+__all__ = ["schema_to_pydantic_model"]

python/packages/autogen-core/src/autogen_core/utils/_json_to_pydantic.py

@@ -0,0 +1,508 @@
+import datetime
+from typing import Annotated, Any, Dict, ForwardRef, List, Literal, Optional, Type, Union
+
+from pydantic import (
+    UUID1,
+    UUID3,
+    UUID4,
+    UUID5,
+    AnyUrl,
+    BaseModel,
+    EmailStr,
+    Field,
+    IPvAnyAddress,
+    conbytes,
+    confloat,
+    conint,
+    conlist,
+    constr,
+    create_model,
+)
+
+
+class SchemaConversionError(Exception):
+    """Base class for schema conversion exceptions."""
+
+    pass
+
+
+class ReferenceNotFoundError(SchemaConversionError):
+    """Raised when a $ref cannot be resolved."""
+
+    pass
+
+
+class FormatNotSupportedError(SchemaConversionError):
+    """Raised when a format is not supported."""
+
+    pass
+
+
+class UnsupportedKeywordError(SchemaConversionError):
+    """Raised when an unsupported JSON Schema keyword is encountered."""
+
+    pass
+
+
+TYPE_MAPPING: Dict[str, Any] = {
+    "string": str,
+    "integer": int,
+    "boolean": bool,
+    "number": float,
+    "array": List,
+    "object": dict,
+    "null": None,
+}
+
+FORMAT_MAPPING: Dict[str, Any] = {
+    "uuid": UUID4,
+    "uuid1": UUID1,
+    "uuid2": UUID4,
+    "uuid3": UUID3,
+    "uuid4": UUID4,
+    "uuid5": UUID5,
+    "email": EmailStr,
+    "uri": AnyUrl,
+    "hostname": constr(strict=True),
+    "ipv4": IPvAnyAddress,
+    "ipv6": IPvAnyAddress,
+    "ipv4-network": IPvAnyAddress,
+    "ipv6-network": IPvAnyAddress,
+    "date-time": datetime.datetime,
+    "date": datetime.date,
+    "time": datetime.time,
+    "duration": datetime.timedelta,
+    "int32": conint(strict=True, ge=-(2**31), le=2**31 - 1),
+    "int64": conint(strict=True, ge=-(2**63), le=2**63 - 1),
+    "float": confloat(strict=True),
+    "double": float,
+    "decimal": float,
+    "byte": conbytes(strict=True),
+    "binary": conbytes(strict=True),
+    "password": str,
+    "path": str,
+}
+
+
+class _JSONSchemaToPydantic:
+    def __init__(self):
+        self._model_cache = {}
+
+    def _resolve_ref(self, ref: str, schema: Dict[str, Any]) -> Dict[str, Any]:
+        ref_key = ref.split("/")[-1]
+        definitions = schema.get("$defs", {})
+
+        if ref_key not in definitions:
+            raise ReferenceNotFoundError(
+                f"Reference `{ref}` not found in `$defs`. Available keys: {list(definitions.keys())}"
+            )
+
+        return definitions[ref_key]
+
+    def get_ref(self, ref_name: str) -> Any:
+        if ref_name not in self._model_cache:
+            raise ReferenceNotFoundError(
+                f"Reference `{ref_name}` not found in cache. Available: {list(self._model_cache.keys())}"
+            )
+
+        if self._model_cache[ref_name] is None:
+            return ForwardRef(ref_name)
+
+        return self._model_cache[ref_name]
+
+    def _process_definitions(self, root_schema: Dict[str, Any]):
+        if "$defs" in root_schema:
+            for model_name in root_schema["$defs"]:
+                if model_name not in self._model_cache:
+                    self._model_cache[model_name] = None
+
+            for model_name, model_schema in root_schema["$defs"].items():
+                if self._model_cache[model_name] is None:
+                    self._model_cache[model_name] = self.json_schema_to_pydantic(model_schema, model_name, root_schema)
+
+    def json_schema_to_pydantic(
+        self, schema: Dict[str, Any], model_name: str = "GeneratedModel", root_schema: Optional[Dict[str, Any]] = None
+    ) -> Type[BaseModel]:
+        if root_schema is None:
+            root_schema = schema
+            self._process_definitions(root_schema)
+
+        if "$ref" in schema:
+            resolved = self._resolve_ref(schema["$ref"], root_schema)
+            schema = {**resolved, **{k: v for k, v in schema.items() if k != "$ref"}}
+
+        if "allOf" in schema:
+            merged = {"type": "object", "properties": {}, "required": []}
+            for s in schema["allOf"]:
+                part = self._resolve_ref(s["$ref"], root_schema) if "$ref" in s else s
+                merged["properties"].update(part.get("properties", {}))
+                merged["required"].extend(part.get("required", []))
+            for k, v in schema.items():
+                if k not in {"allOf", "properties", "required"}:
+                    merged[k] = v
+            merged["required"] = list(set(merged["required"]))
+            schema = merged
+
+        return self._json_schema_to_model(schema, model_name, root_schema)
+
+    def _resolve_union_types(self, schemas: List[Dict[str, Any]]) -> List[Any]:
+        types = []
+        for s in schemas:
+            if "$ref" in s:
+                types.append(self.get_ref(s["$ref"].split("/")[-1]))
+            elif "enum" in s:
+                types.append(Literal[tuple(s["enum"])] if len(s["enum"]) > 0 else Any)
+            else:
+                json_type = s.get("type")
+                if json_type not in TYPE_MAPPING:
+                    raise UnsupportedKeywordError(f"Unsupported or missing type `{json_type}` in union")
+                types.append(TYPE_MAPPING[json_type])
+        return types
+
+    def _extract_field_type(self, key: str, value: Dict[str, Any], model_name: str, root_schema: Dict[str, Any]) -> Any:
+        json_type = value.get("type")
+        if json_type not in TYPE_MAPPING:
+            raise UnsupportedKeywordError(
+                f"Unsupported or missing type `{json_type}` for field `{key}` in `{model_name}`"
+            )
+
+        base_type = TYPE_MAPPING[json_type]
+        constraints = {}
+
+        if json_type == "string":
+            if "minLength" in value:
+                constraints["min_length"] = value["minLength"]
+            if "maxLength" in value:
+                constraints["max_length"] = value["maxLength"]
+            if "pattern" in value:
+                constraints["pattern"] = value["pattern"]
+            if constraints:
+                base_type = constr(**constraints)
+
+        elif json_type == "integer":
+            if "minimum" in value:
+                constraints["ge"] = value["minimum"]
+            if "maximum" in value:
+                constraints["le"] = value["maximum"]
+            if "exclusiveMinimum" in value:
+                constraints["gt"] = value["exclusiveMinimum"]
+            if "exclusiveMaximum" in value:
+                constraints["lt"] = value["exclusiveMaximum"]
+            if constraints:
+                base_type = conint(**constraints)
+
+        elif json_type == "number":
+            if "minimum" in value:
+                constraints["ge"] = value["minimum"]
+            if "maximum" in value:
+                constraints["le"] = value["maximum"]
+            if "exclusiveMinimum" in value:
+                constraints["gt"] = value["exclusiveMinimum"]
+            if "exclusiveMaximum" in value:
+                constraints["lt"] = value["exclusiveMaximum"]
+            if constraints:
+                base_type = confloat(**constraints)
+
+        elif json_type == "array":
+            if "minItems" in value:
+                constraints["min_length"] = value["minItems"]
+            if "maxItems" in value:
+                constraints["max_length"] = value["maxItems"]
+            item_schema = value.get("items", {"type": "string"})
+            if "$ref" in item_schema:
+                item_type = self.get_ref(item_schema["$ref"].split("/")[-1])
+            else:
+                item_type_name = item_schema.get("type")
+                if item_type_name not in TYPE_MAPPING:
+                    raise UnsupportedKeywordError(
+                        f"Unsupported or missing item type `{item_type_name}` for array field `{key}` in `{model_name}`"
+                    )
+                item_type = TYPE_MAPPING[item_type_name]
+
+            base_type = conlist(item_type, **constraints) if constraints else List[item_type]
+
+        if "format" in value:
+            format_type = FORMAT_MAPPING.get(value["format"])
+            if format_type is None:
+                raise FormatNotSupportedError(f"Unknown format `{value['format']}` for `{key}` in `{model_name}`")
+            if not isinstance(format_type, type):
+                return format_type
+            if not issubclass(format_type, str):
+                return format_type
+            return format_type
+
+        return base_type
+
+    def _json_schema_to_model(
+        self, schema: Dict[str, Any], model_name: str, root_schema: Dict[str, Any]
+    ) -> Type[BaseModel]:
+        if "allOf" in schema:
+            merged = {"type": "object", "properties": {}, "required": []}
+            for s in schema["allOf"]:
+                part = self._resolve_ref(s["$ref"], root_schema) if "$ref" in s else s
+                merged["properties"].update(part.get("properties", {}))
+                merged["required"].extend(part.get("required", []))
+            for k, v in schema.items():
+                if k not in {"allOf", "properties", "required"}:
+                    merged[k] = v
+            merged["required"] = list(set(merged["required"]))
+            schema = merged
+
+        fields = {}
+        required_fields = set(schema.get("required", []))
+
+        for key, value in schema.get("properties", {}).items():
+            if "$ref" in value:
+                ref_name = value["$ref"].split("/")[-1]
+                field_type = self.get_ref(ref_name)
+            elif "anyOf" in value:
+                sub_models = self._resolve_union_types(value["anyOf"])
+                field_type = Union[tuple(sub_models)]
+            elif "oneOf" in value:
+                sub_models = self._resolve_union_types(value["oneOf"])
+                field_type = Union[tuple(sub_models)]
+                if "discriminator" in value:
+                    discriminator = value["discriminator"]["propertyName"]
+                    field_type = Annotated[field_type, Field(discriminator=discriminator)]
+            elif "enum" in value:
+                field_type = Literal[tuple(value["enum"])]
+            elif "allOf" in value:
+                merged = {"type": "object", "properties": {}, "required": []}
+                for s in value["allOf"]:
+                    part = self._resolve_ref(s["$ref"], root_schema) if "$ref" in s else s
+                    merged["properties"].update(part.get("properties", {}))
+                    merged["required"].extend(part.get("required", []))
+                for k, v in value.items():
+                    if k not in {"allOf", "properties", "required"}:
+                        merged[k] = v
+                merged["required"] = list(set(merged["required"]))
+                field_type = self._json_schema_to_model(merged, f"{model_name}_{key}", root_schema)
+            elif value.get("type") == "object" and "properties" in value:
+                field_type = self._json_schema_to_model(value, f"{model_name}_{key}", root_schema)
+            else:
+                field_type = self._extract_field_type(key, value, model_name, root_schema)
+
+            if field_type is None:
+                raise UnsupportedKeywordError(f"Unsupported or missing type for field `{key}` in `{model_name}`")
+
+            default_value = value.get("default")
+            is_required = key in required_fields
+
+            if not is_required and default_value is None:
+                field_type = Optional[field_type]
+
+            field_args = {
+                "default": default_value if not is_required else ...,
+            }
+            if "title" in value:
+                field_args["title"] = value["title"]
+            if "description" in value:
+                field_args["description"] = value["description"]
+
+            fields[key] = (field_type, Field(**field_args))
+
+        model = create_model(model_name, **fields)
+        model.model_rebuild()
+        return model
+
+
+def schema_to_pydantic_model(schema: Dict[str, Any], model_name: str = "GeneratedModel") -> Type[BaseModel]:
+    """
+    Convert a JSON Schema dictionary to a fully-typed Pydantic model.
+
+    This function handles schema translation and validation logic to produce
+    a Pydantic model.
+
+    **Supported JSON Schema Features**
+
+    - **Primitive types**: `string`, `integer`, `number`, `boolean`, `object`, `array`, `null`
+    - **String formats**:
+        - `email`, `uri`, `uuid`, `uuid1`, `uuid3`, `uuid4`, `uuid5`
+        - `hostname`, `ipv4`, `ipv6`, `ipv4-network`, `ipv6-network`
+        - `date`, `time`, `date-time`, `duration`
+        - `byte`, `binary`, `password`, `path`
+    - **String constraints**:
+        - `minLength`, `maxLength`, `pattern`
+    - **Numeric constraints**:
+        - `minimum`, `maximum`, `exclusiveMinimum`, `exclusiveMaximum`
+    - **Array constraints**:
+        - `minItems`, `maxItems`, `items`
+    - **Object schema support**:
+        - `properties`, `required`, `title`, `description`, `default`
+    - **Enums**:
+        - Converted to Python `Literal` type
+    - **Union types**:
+        - `anyOf`, `oneOf` supported with optional `discriminator`
+    - **Inheritance and composition**:
+        - `allOf` merges multiple schemas into one model
+    - **$ref and $defs resolution**:
+        - Supports references to sibling definitions and self-referencing schemas
+
+    .. code-block:: python
+
+        from json_schema_to_pydantic import schema_to_pydantic_model
+
+        # Example 1: Simple user model
+        schema = {
+            "title": "User",
+            "type": "object",
+            "properties": {
+                "name": {"type": "string"},
+                "email": {"type": "string", "format": "email"},
+                "age": {"type": "integer", "minimum": 0},
+            },
+            "required": ["name", "email"],
+        }
+
+        UserModel = schema_to_pydantic_model(schema)
+        user = UserModel(name="Alice", email="alice@example.com", age=30)
+
+    .. code-block:: python
+
+        # Example 2: Nested model
+        schema = {
+            "title": "BlogPost",
+            "type": "object",
+            "properties": {
+                "title": {"type": "string"},
+                "tags": {"type": "array", "items": {"type": "string"}},
+                "author": {
+                    "type": "object",
+                    "properties": {"name": {"type": "string"}, "email": {"type": "string", "format": "email"}},
+                    "required": ["name"],
+                },
+            },
+            "required": ["title", "author"],
+        }
+
+        BlogPost = schema_to_pydantic_model(schema)
+
+    .. code-block:: python
+
+        # Example 3: allOf merging with $refs
+        schema = {
+            "title": "EmployeeWithDepartment",
+            "allOf": [{"$ref": "#/$defs/Employee"}, {"$ref": "#/$defs/Department"}],
+            "$defs": {
+                "Employee": {
+                    "type": "object",
+                    "properties": {"id": {"type": "string"}, "name": {"type": "string"}},
+                    "required": ["id", "name"],
+                },
+                "Department": {
+                    "type": "object",
+                    "properties": {"department": {"type": "string"}},
+                    "required": ["department"],
+                },
+            },
+        }
+
+        Model = schema_to_pydantic_model(schema)
+
+    .. code-block:: python
+
+        # Example 4: Self-referencing (recursive) model
+        schema = {
+            "title": "Category",
+            "type": "object",
+            "properties": {
+                "name": {"type": "string"},
+                "subcategories": {"type": "array", "items": {"$ref": "#/$defs/Category"}},
+            },
+            "required": ["name"],
+            "$defs": {
+                "Category": {
+                    "type": "object",
+                    "properties": {
+                        "name": {"type": "string"},
+                        "subcategories": {"type": "array", "items": {"$ref": "#/$defs/Category"}},
+                    },
+                    "required": ["name"],
+                }
+            },
+        }
+
+        Category = schema_to_pydantic_model(schema)
+
+    .. code-block:: python
+
+        # Example 5: Serializing and deserializing with Pydantic
+
+        from uuid import uuid4
+        from pydantic import BaseModel, EmailStr, Field
+        from typing import Optional, List, Dict, Any
+        from autogen_core.utils import schema_to_pydantic_model
+
+
+        class Address(BaseModel):
+            street: str
+            city: str
+            zipcode: str
+
+
+        class User(BaseModel):
+            id: str
+            name: str
+            email: EmailStr
+            age: int = Field(..., ge=18)
+            address: Address
+
+
+        class Employee(BaseModel):
+            id: str
+            name: str
+            manager: Optional["Employee"] = None
+
+
+        class Department(BaseModel):
+            name: str
+            employees: List[Employee]
+
+
+        class ComplexModel(BaseModel):
+            user: User
+            extra_info: Optional[Dict[str, Any]] = None
+            sub_items: List[Employee]
+
+
+        # Convert ComplexModel to JSON schema
+        complex_schema = ComplexModel.model_json_schema()
+
+        # Rebuild a new Pydantic model from JSON schema
+        ReconstructedModel = schema_to_pydantic_model(complex_schema, "ComplexModel")
+
+        # Instantiate reconstructed model
+        reconstructed = ReconstructedModel(
+            user={
+                "id": str(uuid4()),
+                "name": "Alice",
+                "email": "alice@example.com",
+                "age": 30,
+                "address": {"street": "123 Main St", "city": "Wonderland", "zipcode": "12345"},
+            },
+            sub_items=[{"id": str(uuid4()), "name": "Bob", "manager": {"id": str(uuid4()), "name": "Eve"}}],
+        )
+
+        print(reconstructed.model_dump())
+
+
+    Args:
+        schema (Dict[str, Any]): A valid JSON Schema dictionary.
+        model_name (str, optional): The name of the root model. Defaults to "GeneratedModel".
+
+    Returns:
+        Type[BaseModel]: A dynamically generated Pydantic model class.
+
+    Raises:
+        ReferenceNotFoundError: If a `$ref` key references a missing entry.
+        FormatNotSupportedError: If a `format` keyword is unknown or unsupported.
+        UnsupportedKeywordError: If the schema contains an unsupported `type`.
+
+    See Also:
+        - :class:`pydantic.BaseModel`
+        - :func:`pydantic.create_model`
+        - https://json-schema.org/
+    """
+    ...
+
+    return _JSONSchemaToPydantic().json_schema_to_pydantic(schema, model_name)

python/packages/autogen-core/tests/test_json_to_pydantic.py

@@ -0,0 +1,656 @@
+from typing import Any, Dict, List, Literal, Optional
+from uuid import UUID, uuid4
+
+import pytest
+from autogen_core.utils._json_to_pydantic import (
+    FormatNotSupportedError,
+    ReferenceNotFoundError,
+    UnsupportedKeywordError,
+    _JSONSchemaToPydantic,
+)
+from pydantic import BaseModel, EmailStr, Field, ValidationError
+
+
+# ✅ Define Pydantic models for testing
+class Address(BaseModel):
+    street: str
+    city: str
+    zipcode: str
+
+
+class User(BaseModel):
+    id: UUID
+    name: str
+    email: EmailStr
+    age: int = Field(..., ge=18)  # Minimum age = 18
+    address: Address
+
+
+class Employee(BaseModel):
+    id: UUID
+    name: str
+    manager: Optional["Employee"] = None  # Recursive self-reference
+
+
+class Department(BaseModel):
+    name: str
+    employees: List[Employee]  # Array of objects
+
+
+class ComplexModel(BaseModel):
+    user: User
+    extra_info: Optional[Dict[str, Any]] = None  # Optional dictionary
+    sub_items: List[Employee]  # List of Employees
+
+
+@pytest.fixture
+def converter():
+    """Fixture to create a fresh instance of JSONSchemaToPydantic for every test."""
+    return _JSONSchemaToPydantic()
+
+
+@pytest.fixture
+def sample_json_schema():
+    """Fixture that returns a JSON schema dynamically using model_json_schema()."""
+    return User.model_json_schema()
+
+
+@pytest.fixture
+def sample_json_schema_recursive():
+    """Fixture that returns a self-referencing JSON schema."""
+    return Employee.model_json_schema()
+
+
+@pytest.fixture
+def sample_json_schema_nested():
+    """Fixture that returns a nested schema with arrays of objects."""
+    return Department.model_json_schema()
+
+
+@pytest.fixture
+def sample_json_schema_complex():
+    """Fixture that returns a complex schema with multiple structures."""
+    return ComplexModel.model_json_schema()
+
+
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, expected_fields",
+    [
+        (sample_json_schema, "User", ["id", "name", "email", "age", "address"]),
+        (sample_json_schema_recursive, "Employee", ["id", "name", "manager"]),
+        (sample_json_schema_nested, "Department", ["name", "employees"]),
+        (sample_json_schema_complex, "ComplexModel", ["user", "extra_info", "sub_items"]),
+    ],
+)
+def test_json_schema_to_pydantic(converter, schema_fixture, model_name, expected_fields, request):
+    """Test conversion of JSON Schema to Pydantic model using the class instance."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    for field in expected_fields:
+        assert field in Model.__annotations__, f"Expected '{field}' missing in {model_name}Model"
+
+
+# ✅ **Valid Data Tests**
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, valid_data",
+    [
+        (
+            sample_json_schema,
+            "User",
+            {
+                "id": str(uuid4()),
+                "name": "Alice",
+                "email": "alice@example.com",
+                "age": 25,
+                "address": {"street": "123 Main St", "city": "Metropolis", "zipcode": "12345"},
+            },
+        ),
+        (
+            sample_json_schema_recursive,
+            "Employee",
+            {
+                "id": str(uuid4()),
+                "name": "Alice",
+                "manager": {
+                    "id": str(uuid4()),
+                    "name": "Bob",
+                },
+            },
+        ),
+        (
+            sample_json_schema_nested,
+            "Department",
+            {
+                "name": "Engineering",
+                "employees": [
+                    {
+                        "id": str(uuid4()),
+                        "name": "Alice",
+                        "manager": {
+                            "id": str(uuid4()),
+                            "name": "Bob",
+                        },
+                    }
+                ],
+            },
+        ),
+        (
+            sample_json_schema_complex,
+            "ComplexModel",
+            {
+                "user": {
+                    "id": str(uuid4()),
+                    "name": "Charlie",
+                    "email": "charlie@example.com",
+                    "age": 30,
+                    "address": {"street": "456 Side St", "city": "Gotham", "zipcode": "67890"},
+                },
+                "extra_info": {"hobby": "Chess", "level": "Advanced"},
+                "sub_items": [
+                    {"id": str(uuid4()), "name": "Eve"},
+                    {"id": str(uuid4()), "name": "David", "manager": {"id": str(uuid4()), "name": "Frank"}},
+                ],
+            },
+        ),
+    ],
+)
+def test_valid_data_model(converter, schema_fixture, model_name, valid_data, request):
+    """Test that valid data is accepted by the generated model."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    instance = Model(**valid_data)
+    assert instance
+    dumped = instance.model_dump(mode="json", exclude_none=True)
+    assert dumped == valid_data, f"Model output mismatch.\nExpected: {valid_data}\nGot: {dumped}"
+
+
+# ✅ **Invalid Data Tests**
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, invalid_data",
+    [
+        (
+            sample_json_schema,
+            "User",
+            {
+                "id": "not-a-uuid",  # Invalid UUID
+                "name": "Alice",
+                "email": "not-an-email",  # Invalid email
+                "age": 17,  # Below minimum
+                "address": {"street": "123 Main St", "city": "Metropolis"},
+            },
+        ),
+        (
+            sample_json_schema_recursive,
+            "Employee",
+            {
+                "id": str(uuid4()),
+                "name": "Alice",
+                "manager": {
+                    "id": "not-a-uuid",  # Invalid UUID
+                    "name": "Bob",
+                },
+            },
+        ),
+        (
+            sample_json_schema_nested,
+            "Department",
+            {
+                "name": "Engineering",
+                "employees": [
+                    {
+                        "id": "not-a-uuid",  # Invalid UUID
+                        "name": "Alice",
+                        "manager": {
+                            "id": str(uuid4()),
+                            "name": "Bob",
+                        },
+                    }
+                ],
+            },
+        ),
+        (
+            sample_json_schema_complex,
+            "ComplexModel",
+            {
+                "user": {
+                    "id": str(uuid4()),
+                    "name": "Charlie",
+                    "email": "charlie@example.com",
+                    "age": "thirty",  # Invalid: Should be an int
+                    "address": {"street": "456 Side St", "city": "Gotham", "zipcode": "67890"},
+                },
+                "extra_info": "should-be-dictionary",  # Invalid type
+                "sub_items": [
+                    {"id": "invalid-uuid", "name": "Eve"},  # Invalid UUID
+                    {"id": str(uuid4()), "name": 123},  # Invalid name type
+                ],
+            },
+        ),
+    ],
+)
+def test_invalid_data_model(converter, schema_fixture, model_name, invalid_data, request):
+    """Test that invalid data raises ValidationError."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    with pytest.raises(ValidationError):
+        Model(**invalid_data)
+
+
+class ListDictModel(BaseModel):
+    """Example for `List[Dict[str, Any]]`"""
+
+    data: List[Dict[str, Any]]
+
+
+class DictListModel(BaseModel):
+    """Example for `Dict[str, List[Any]]`"""
+
+    mapping: Dict[str, List[Any]]
+
+
+class NestedListModel(BaseModel):
+    """Example for `List[List[str]]`"""
+
+    matrix: List[List[str]]
+
+
+@pytest.fixture
+def sample_json_schema_list_dict():
+    """Fixture for `List[Dict[str, Any]]`"""
+    return ListDictModel.model_json_schema()
+
+
+@pytest.fixture
+def sample_json_schema_dict_list():
+    """Fixture for `Dict[str, List[Any]]`"""
+    return DictListModel.model_json_schema()
+
+
+@pytest.fixture
+def sample_json_schema_nested_list():
+    """Fixture for `List[List[str]]`"""
+    return NestedListModel.model_json_schema()
+
+
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, expected_fields",
+    [
+        (sample_json_schema_list_dict, "ListDictModel", ["data"]),
+        (sample_json_schema_dict_list, "DictListModel", ["mapping"]),
+        (sample_json_schema_nested_list, "NestedListModel", ["matrix"]),
+    ],
+)
+def test_json_schema_to_pydantic_nested(converter, schema_fixture, model_name, expected_fields, request):
+    """Test conversion of JSON Schema to Pydantic model using the class instance."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    for field in expected_fields:
+        assert field in Model.__annotations__, f"Expected '{field}' missing in {model_name}Model"
+
+
+# ✅ **Valid Data Tests**
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, valid_data",
+    [
+        (
+            sample_json_schema_list_dict,
+            "ListDictModel",
+            {
+                "data": [
+                    {"key1": "value1", "key2": 10},
+                    {"another_key": False, "nested": {"subkey": "data"}},
+                ]
+            },
+        ),
+        (
+            sample_json_schema_dict_list,
+            "DictListModel",
+            {
+                "mapping": {
+                    "first": ["a", "b", "c"],
+                    "second": [1, 2, 3, 4],
+                    "third": [True, False, True],
+                }
+            },
+        ),
+        (
+            sample_json_schema_nested_list,
+            "NestedListModel",
+            {"matrix": [["A", "B"], ["C", "D"], ["E", "F"]]},
+        ),
+    ],
+)
+def test_valid_data_model_nested(converter, schema_fixture, model_name, valid_data, request):
+    """Test that valid data is accepted by the generated model."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    instance = Model(**valid_data)
+    assert instance
+    for field, value in valid_data.items():
+        assert (
+            getattr(instance, field) == value
+        ), f"Mismatch in field `{field}`: expected `{value}`, got `{getattr(instance, field)}`"
+
+
+# ✅ **Invalid Data Tests**
+@pytest.mark.parametrize(
+    "schema_fixture, model_name, invalid_data",
+    [
+        (
+            sample_json_schema_list_dict,
+            "ListDictModel",
+            {
+                "data": "should-be-a-list",  # ❌ Should be a list of dicts
+            },
+        ),
+        (
+            sample_json_schema_dict_list,
+            "DictListModel",
+            {
+                "mapping": [
+                    "should-be-a-dictionary",  # ❌ Should be a dict of lists
+                ]
+            },
+        ),
+        (
+            sample_json_schema_nested_list,
+            "NestedListModel",
+            {"matrix": [["A", "B"], "C", ["D", "E"]]},  # ❌ "C" is not a list
+        ),
+    ],
+)
+def test_invalid_data_model_nested(converter, schema_fixture, model_name, invalid_data, request):
+    """Test that invalid data raises ValidationError."""
+    schema = request.getfixturevalue(schema_fixture.__name__)
+    Model = converter.json_schema_to_pydantic(schema, model_name)
+
+    with pytest.raises(ValidationError):
+        Model(**invalid_data)
+
+
+def test_reference_not_found(converter):
+    schema = {"type": "object", "properties": {"manager": {"$ref": "#/$defs/MissingRef"}}}
+    with pytest.raises(ReferenceNotFoundError):
+        converter.json_schema_to_pydantic(schema, "MissingRefModel")
+
+
+def test_format_not_supported(converter):
+    schema = {"type": "object", "properties": {"custom_field": {"type": "string", "format": "unsupported-format"}}}
+    with pytest.raises(FormatNotSupportedError):
+        converter.json_schema_to_pydantic(schema, "UnsupportedFormatModel")
+
+
+def test_unsupported_keyword(converter):
+    schema = {"type": "object", "properties": {"broken_field": {"title": "Missing type"}}}
+    with pytest.raises(UnsupportedKeywordError):
+        converter.json_schema_to_pydantic(schema, "MissingTypeModel")
+
+
+def test_enum_field_schema():
+    schema = {
+        "type": "object",
+        "properties": {
+            "status": {"type": "string", "enum": ["pending", "approved", "rejected"]},
+            "priority": {"type": "integer", "enum": [1, 2, 3]},
+        },
+        "required": ["status"],
+    }
+
+    converter = _JSONSchemaToPydantic()
+    Model = converter.json_schema_to_pydantic(schema, "Task")
+
+    assert Model.model_fields["status"].annotation == Literal["pending", "approved", "rejected"]
+    assert Model.model_fields["priority"].annotation == Optional[Literal[1, 2, 3]]
+
+    instance = Model(status="approved", priority=2)
+    assert instance.status == "approved"
+    assert instance.priority == 2
+
+
+def test_metadata_title_description(converter):
+    schema = {
+        "title": "CustomerProfile",
+        "description": "A profile containing personal and contact info",
+        "type": "object",
+        "properties": {
+            "first_name": {"type": "string", "title": "First Name", "description": "Given name of the user"},
+            "age": {"type": "integer", "title": "Age", "description": "Age in years"},
+            "contact": {
+                "type": "object",
+                "title": "Contact Information",
+                "description": "How to reach the user",
+                "properties": {
+                    "email": {
+                        "type": "string",
+                        "format": "email",
+                        "title": "Email Address",
+                        "description": "Primary email",
+                    }
+                },
+            },
+        },
+        "required": ["first_name"],
+    }
+
+    Model = converter.json_schema_to_pydantic(schema, "CustomerProfile")
+    generated_schema = Model.model_json_schema()
+
+    assert generated_schema["title"] == "CustomerProfile"
+
+    props = generated_schema["properties"]
+    assert props["first_name"]["title"] == "First Name"
+    assert props["first_name"]["description"] == "Given name of the user"
+    assert props["age"]["title"] == "Age"
+    assert props["age"]["description"] == "Age in years"
+
+    contact = props["contact"]
+    assert contact["title"] == "Contact Information"
+    assert contact["description"] == "How to reach the user"
+
+    # Follow the $ref
+    ref_key = contact["anyOf"][0]["$ref"].split("/")[-1]
+    contact_def = generated_schema["$defs"][ref_key]
+    email = contact_def["properties"]["email"]
+    assert email["title"] == "Email Address"
+    assert email["description"] == "Primary email"
+
+
+def test_oneof_with_discriminator(converter):
+    schema = {
+        "title": "PetWrapper",
+        "type": "object",
+        "properties": {
+            "pet": {
+                "oneOf": [{"$ref": "#/$defs/Cat"}, {"$ref": "#/$defs/Dog"}],
+                "discriminator": {"propertyName": "pet_type"},
+            }
+        },
+        "required": ["pet"],
+        "$defs": {
+            "Cat": {
+                "type": "object",
+                "properties": {"pet_type": {"type": "string", "enum": ["cat"]}, "hunting_skill": {"type": "string"}},
+                "required": ["pet_type", "hunting_skill"],
+                "title": "Cat",
+            },
+            "Dog": {
+                "type": "object",
+                "properties": {"pet_type": {"type": "string", "enum": ["dog"]}, "pack_size": {"type": "integer"}},
+                "required": ["pet_type", "pack_size"],
+                "title": "Dog",
+            },
+        },
+    }
+
+    Model = converter.json_schema_to_pydantic(schema, "PetWrapper")
+
+    # Instantiate with a Cat
+    cat = Model(pet={"pet_type": "cat", "hunting_skill": "expert"})
+    assert cat.pet.pet_type == "cat"
+
+    # Instantiate with a Dog
+    dog = Model(pet={"pet_type": "dog", "pack_size": 4})
+    assert dog.pet.pet_type == "dog"
+
+    # Check round-trip schema includes discriminator
+    model_schema = Model.model_json_schema()
+    assert "discriminator" in model_schema["properties"]["pet"]
+    assert model_schema["properties"]["pet"]["discriminator"]["propertyName"] == "pet_type"
+
+
+def test_allof_merging_with_refs(converter):
+    schema = {
+        "title": "EmployeeWithDepartment",
+        "allOf": [{"$ref": "#/$defs/Employee"}, {"$ref": "#/$defs/Department"}],
+        "$defs": {
+            "Employee": {
+                "type": "object",
+                "properties": {"id": {"type": "string"}, "name": {"type": "string"}},
+                "required": ["id", "name"],
+                "title": "Employee",
+            },
+            "Department": {
+                "type": "object",
+                "properties": {"department": {"type": "string"}},
+                "required": ["department"],
+                "title": "Department",
+            },
+        },
+    }
+
+    Model = converter.json_schema_to_pydantic(schema, "EmployeeWithDepartment")
+    instance = Model(id="123", name="Alice", department="Engineering")
+    assert instance.id == "123"
+    assert instance.name == "Alice"
+    assert instance.department == "Engineering"
+
+    dumped = instance.model_dump()
+    assert dumped == {"id": "123", "name": "Alice", "department": "Engineering"}
+
+
+def test_nested_allof_merging(converter):
+    schema = {
+        "title": "ContainerModel",
+        "type": "object",
+        "properties": {
+            "nested": {
+                "type": "object",
+                "properties": {
+                    "data": {
+                        "allOf": [
+                            {"$ref": "#/$defs/Base"},
+                            {"type": "object", "properties": {"extra": {"type": "string"}}, "required": ["extra"]},
+                        ]
+                    }
+                },
+                "required": ["data"],
+            }
+        },
+        "required": ["nested"],
+        "$defs": {
+            "Base": {
+                "type": "object",
+                "properties": {"base_field": {"type": "string"}},
+                "required": ["base_field"],
+                "title": "Base",
+            }
+        },
+    }
+
+    Model = converter.json_schema_to_pydantic(schema, "ContainerModel")
+    instance = Model(nested={"data": {"base_field": "abc", "extra": "xyz"}})
+
+    assert instance.nested.data.base_field == "abc"
+    assert instance.nested.data.extra == "xyz"
+
+
+@pytest.mark.parametrize(
+    "schema, field_name, valid_values, invalid_values",
+    [
+        # String constraints
+        (
+            {
+                "type": "object",
+                "properties": {
+                    "username": {"type": "string", "minLength": 3, "maxLength": 10, "pattern": "^[a-zA-Z0-9_]+$"}
+                },
+                "required": ["username"],
+            },
+            "username",
+            ["user_123", "abc", "Name2023"],
+            ["", "ab", "toolongusername123", "invalid!char"],
+        ),
+        # Integer constraints
+        (
+            {
+                "type": "object",
+                "properties": {"age": {"type": "integer", "minimum": 18, "maximum": 99}},
+                "required": ["age"],
+            },
+            "age",
+            [18, 25, 99],
+            [17, 100, -1],
+        ),
+        # Float constraints
+        (
+            {
+                "type": "object",
+                "properties": {"score": {"type": "number", "minimum": 0.0, "exclusiveMaximum": 1.0}},
+                "required": ["score"],
+            },
+            "score",
+            [0.0, 0.5, 0.999],
+            [-0.1, 1.0, 2.5],
+        ),
+        # Array constraints
+        (
+            {
+                "type": "object",
+                "properties": {"tags": {"type": "array", "items": {"type": "string"}, "minItems": 1, "maxItems": 3}},
+                "required": ["tags"],
+            },
+            "tags",
+            [["a"], ["a", "b"], ["x", "y", "z"]],
+            [[], ["one", "two", "three", "four"]],
+        ),
+    ],
+)
+def test_field_constraints(schema, field_name, valid_values, invalid_values):
+    converter = _JSONSchemaToPydantic()
+    Model = converter.json_schema_to_pydantic(schema, "ConstraintModel")
+
+    import json
+
+    for value in valid_values:
+        instance = Model(**{field_name: value})
+        assert getattr(instance, field_name) == value
+
+    for value in invalid_values:
+        with pytest.raises(ValidationError):
+            Model(**{field_name: value})
+
+
+@pytest.mark.parametrize(
+    "schema",
+    [
+        # Top-level field
+        {"type": "object", "properties": {"weird": {"type": "abc"}}, "required": ["weird"]},
+        # Inside array items
+        {"type": "object", "properties": {"items": {"type": "array", "items": {"type": "abc"}}}, "required": ["items"]},
+        # Inside anyOf
+        {
+            "type": "object",
+            "properties": {"choice": {"anyOf": [{"type": "string"}, {"type": "abc"}]}},
+            "required": ["choice"],
+        },
+    ],
+)
+def test_unknown_type_raises(schema):
+    converter = _JSONSchemaToPydantic()
+    with pytest.raises(UnsupportedKeywordError):
+        converter.json_schema_to_pydantic(schema, "UnknownTypeModel")