# Validation alias


@app.post("/optional-list-bytes-validation-alias")
def read_optional_list_bytes_validation_alias(
    p: Annotated[Optional[list[bytes]], File(validation_alias="p_val_alias")] = None,
):
    return {"file_size": [len(file) for file in p] if p else None}


@app.post("/optional-list-uploadfile-validation-alias")

        ),
        pytest.param(
            "/required-validation-alias/{p_val_alias}",
            "p_val_alias",
            "P Val Alias",
            id="required-validation-alias",
        ),
        pytest.param(
            "/required-alias-and-validation-alias/{p_val_alias}",
            "p_val_alias",
            "P Val Alias",
            id="required-alias-and-validation-alias",
        ),
    ],
)

But by default, it all **"just works"**.

### Validation { #validation }

* Validation for most (or all?) Python **data types**, including:
    * JSON objects (`dict`).
    * JSON array (`list`) defining item types.
    * String (`str`) fields, defining min and max lengths.
    * Numbers (`int`, `float`) with min and max values, etc.

* Validation for more exotic types, like:
    * URL.
    * Email.

   ** file model validation: <<<ModelValidator>>> ({{{./apidocs/org/apache/maven/model/validation/ModelValidator.html}javadoc}}),
   with its <<<DefaultModelValidator>>> implementation
   ({{{./xref/org/apache/maven/model/validation/DefaultModelValidator.html}source}})

   []

 * phase 2, with optional plugin processing

    /**
     * Denotes validation as performed by Maven 3.0. This validation level is meant for existing projects.
     */
    int VALIDATION_LEVEL_MAVEN_3_0 = 30;

    /**
     * Denotes validation as performed by Maven 3.1. This validation level is meant for new projects.
     */
    int VALIDATION_LEVEL_MAVEN_3_1 = 31;

    /**
     * Denotes strict validation as recommended by the current Maven version.
     */

                            "content": {"application/json": {"schema": {}}},
                        },
                        "422": {
                            "description": "Validation Error",
                            "content": {
                                "application/json": {
                                    "schema": {

 *   <li>Downloading parent POMs and dependency POMs</li>
 *   <li>Retrieving version information and ranges</li>
 *   <li>Accessing plugin artifacts and their dependencies</li>
 * </ul>
 *
 * <p>Repository validation ensures data integrity by:
 * <ul>
 *   <li>Preventing duplicate repositories that could cause confusion</li>
 *   <li>Rejecting null repository entries that would cause failures</li>

As these keys may not necessarily be part of the OpenAPI specification, some OpenAPI tools, for example [the OpenAPI validator](https://validator.swagger.io/), may not work with your generated schema.

///

## Recap { #recap }

You can use Pydantic's `Field` to declare extra validations and metadata for model attributes.

                                    }
                                },
                            },
                            "422": {
                                "description": "Validation Error",
                                "content": {
                                    "application/json": {
                                        "schema": {

    assert response.json() == {"exception": "http-exception"}


def test_override_request_validation_exception():
    response = client.get("/request-validation/invalid")
    assert response.status_code == 200
    assert response.json() == {"exception": "request-validation"}


def test_override_server_error_exception_raises():
    with pytest.raises(RuntimeError):
        client.get("/server-error")