options.md

mercurius-validation

• Plugin options

Plugin options

mercurius-validation supports the following options:

Extends: AJVOptions

• mode "JSONSchema" | "JTD" (optional, default: "JSONSchema") - the validation mode of the plugin. This is used to specify the type of schema that needs to be compiled.
• schema MercuriusValidationSchema (optional) - the validation schema definition that the plugin with run. One can define JSON Schema or JTD definitions for GraphQL types, fields and arguments or functions for GraphQL arguments.
• directiveValidation boolean (optional, default: true) - turn directive validation on or off. It is on by default.
• customTypeInferenceFn Function (optional) - add custom type inference for JSON Schema Types. This function overrides the default type inference logic which infers GraphQL primitives like GraphQLString, GraphQLInt and GraphQLFloat. If the custom function doesn't handle the passed type, then it should return a falsy value which will trigger the default type inference logic of the plugin. This function takes two parameters. The first parameter is type referring to the GraphQL type under inference, while the second one is isNonNull, a boolean value referring whether the value for the type is nullable.

It extends the AJV options. These can be used to register additional formats for example and provide further customization to the AJV validation behavior.

Parameter: MercuriusValidationSchema

Extends: Record<string, MercuriusValidationSchemaType>

Each key within the MercuriusValidationSchema type corresponds with the GraphQL type name. For example, if we wanted validation on input type:

input Filters {
  ...
}

We would use the key: Filters:

{
  Filters: { ... }
}

Parameter: MercuriusValidationSchemaType

Extends: Record<string, MercuriusValidationSchemaField>

• __typeValidation JSONSchema | JTD (optional) - The JSON Schema or JTD schema definitions for the type. This is only applicable to GraphQL Input object types, so only schema definitions for object are applicable here.

Each key within the MercuriusValidationSchemaType type corresponds with the GraphQL field name on a type. For example, if we wanted validation on type field text:

input Filters {
  id: ID
  text: String
}

We would use the key: text:

{
  Filters: {
    text: { ... }
  }
}

Parameter: MercuriusValidationSchemaField

The field definition is different for GraphQL Input Object types and GraphQL Object types.

GraphQL Input Object Types

Union: JSONSchema | JTD

GraphQL Object Types

Extends: Record<string, MercuriusValidationSchemaArgument>

Each key within the MercuriusValidationSchemaField type corresponds with the GraphQL argument name on a field. For example, if we wanted validation on field argument id:

type Query {
  message(id: ID): String
}

We would use the key: id:

{
  Query: {
    message: {
      id: {... }
    }
  }
}

Parameter: MercuriusValidationSchemaArgument

Union: JSONSchema | JTD | MercuriusValidationFunction

Parameter: MercuriusValidationFunction(metadata, value, parent, arguments, context, info)

Arguments:

• metadata MercuriusValidationFunctionMetadata - the GraphQL argument metadata associated with the function definition.
• value any - the value of the argument.
• parent object - the parent data associated with the GraphQL field.
• arguments object - the key value object of the GraphQL field arguments.
• context MercuriusContext - the Mercurius context.
• info GraphQLResolveInfo - the GraphQL Resolve info of the object type.

Parameter: MercuriusValidationFunctionMetadata

• type string - the name of the associated GraphQL type.
• field string - the name of the associated GraphQL field.
• argument string - the name of the associated GraphQL argument.

Returns: void

Parameter: JSONSchema

The JSON Schema schema definition for the input object type, type field or field argument.

Parameter: JTD

The JTD schema definition for the input object type, type field or field argument.