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Add Validation Rules

docs/extensions/add-validation-rules.md

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AddValidationRules

This extension allows you add custom validation rules.

See graphql.validation.rules.custom for some custom rules that can be added from GraphQl-core.

Usage example:

python
import strawberry
from strawberry.extensions import AddValidationRules
from graphql import ValidationRule


@strawberry.type
class Query:
    @strawberry.field
    def hello(self) -> str:
        return "Hello, world!"


class MyCustomRule(ValidationRule): ...


schema = strawberry.Schema(
    Query,
    extensions=[
        AddValidationRules(MyCustomRule),
    ],
)

API reference:

python
class AddValidationRules(validation_rules): ...

validation_rules: List[Type[ASTValidationRule]]

List of GraphQL validation rules.

More examples:

<details> <summary>Adding a custom rule</summary>
python
import strawberry
from strawberry.extensions import AddValidationRules
from graphql import ValidationRule


@strawberry.type
class Query:
    @strawberry.field
    def hello(self) -> str:
        return "Hello, world!"


class CustomRule(ValidationRule):
    def enter_field(self, node, *args) -> None:
        if node.name.value == "example":
            self.report_error(GraphQLError("Can't query field 'example'"))


schema = strawberry.Schema(
    Query,
    extensions=[
        AddValidationRules([CustomRule]),
    ],
)

result = schema.execute_sync("{ example }")

assert str(result.errors[0]) == "Can't query field 'example'"
</details> <details> <summary>Adding the `NoDeprecatedCustomRule` from GraphQL-core</summary>
python
import strawberry
from strawberry.extensions import AddValidationRules
from graphql.validation import NoDeprecatedCustomRule


@strawberry.type
class Query:
    @strawberry.field
    def hello(self) -> str:
        return "Hello, world!"


schema = strawberry.Schema(
    Query,
    extensions=[
        AddValidationRules([NoDeprecatedCustomRule]),
    ],
)
</details> <details> <summary>Adding the `NoSchemaIntrospectionCustomRule` from GraphQL-core</summary>
python
import strawberry
from strawberry.extensions import AddValidationRules
from graphql.validation import NoSchemaIntrospectionCustomRule


@strawberry.type
class Query:
    @strawberry.field
    def hello(self) -> str:
        return "Hello, world!"


schema = strawberry.Schema(
    Query,
    extensions=[
        AddValidationRules([NoSchemaIntrospectionCustomRule]),
    ],
)
</details>