@tsed/schema/lib/types/domain/JsonDiscriminator.d.ts

JsonSchema module for Ts.ED Framework

import { Type } from "@tsed/core";
/**
 * Manages discriminator mappings for polymorphic type resolution.
 *
 * A discriminator enables polymorphism in schemas by using a specific property
 * value to determine which subtype schema to apply. This is essential for
 * inheritance hierarchies and union types in OpenAPI specifications.
 *
 * ### Concept
 *
 * When a base class has multiple derived classes, the discriminator property
 * (e.g., "type", "kind") indicates which concrete class an object represents.
 *
 * ### Usage
 *
 * ```typescript
 * // Base class
 * @DiscriminatorKey("type")
 * abstract class Animal {
 *   type: string;
 * }
 *
 * // Derived classes
 * @DiscriminatorValue("dog")
 * class Dog extends Animal {
 *   breed: string;
 * }
 *
 * @DiscriminatorValue("cat")
 * class Cat extends Animal {
 *   indoor: boolean;
 * }
 * ```
 *
 * ### OpenAPI Mapping
 *
 * Generates OpenAPI discriminator objects:
 * ```json
 * {
 *   "discriminator": {
 *     "propertyName": "type",
 *     "mapping": {
 *       "dog": "#/components/schemas/Dog",
 *       "cat": "#/components/schemas/Cat"
 *     }
 *   }
 * }
 * ```
 *
 * ### Key Features
 *
 * - **Type Mapping**: Maps discriminator values to TypeScript classes
 * - **Bidirectional Lookup**: Find type by value or values by type
 * - **Default Values**: Get the default discriminator value for a type
 * - **Children Discovery**: List all derived types
 *
 * @public
 */
export declare class Discriminator {
    propertyName: string;
    base: Type<any>;
    values: Map<string, Type>;
    types: Map<Type, string[]>;
    constructor({ base, propertyName, types, values }?: Partial<{
        base: Type<any>;
        propertyName: string;
        values: Map<string, Type<any>>;
        types: Map<Type, string[]>;
    }>);
    add(type: Type<string>, values: string[]): this;
    getType(discriminatorValue: string): Type<any>;
    getValues(type: Type): string[] | undefined;
    getDefaultValue(type: Type<any>): string | undefined;
    children(): Type<any>[];
}