"""Helper functions to use with handlers."""

from functools import wraps

from artwork.utils import exception
from flask import request
from marshmallow import ValidationError


def validate_request_data(schema, partial=False):
    """Decorate requests' input data validation.

    Args:
        schema (marshmallow.Schema()): schema instance to apply
        partial (bool): validate only derived fields

    """

    def validator(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            data = request.get_json()
            try:
                schema.load(data, partial=partial)
            except ValidationError as err:
                # bubble the error back up
                # to be handled by the @app.errorhandler
                exception.reraise_exception(err)
            else:
                return func(*args, **kwargs)

        return wrapper

    return validator