fastify-swagger: Example not working with TS project because of swagger-schema-official types bug

🐛 Bug Report

The example provided in the README.md doesn’t work with typescript because Schema type doesn’t have .

This is a swagger-schema-official types bug and i am writing it here just for reference.

To Reproduce

Just copy-paste the example in a TS project and you will get:

No overload matches this call.
  Overload 2 of 3, '(plugin: FastifyPluginAsync<SwaggerOptions, Server>, opts?: (RegisterOptions & FastifyStaticSwaggerOptions) | (RegisterOptions & FastifyDynamicSwaggerOptions) | (() => (RegisterOptions & FastifyStaticSwaggerOptions) | (RegisterOptions & FastifyDynamicSwaggerOptions)) | undefined): FastifyInstance<...> & PromiseLike<...>', gave the following error.
    Argument of type 'FastifyPlugin<SwaggerOptions>' is not assignable to parameter of type 'FastifyPluginAsync<SwaggerOptions, Server>'.
      Type 'FastifyPluginCallback<SwaggerOptions, Server>' is not assignable to type 'FastifyPluginAsync<SwaggerOptions, Server>'.

Digging more into this i found that leaving just one of the nullable fields displays the correct error. Object literal may only specify known properties, and 'nullable' does not exist in type 'Schema'

this is the Schema definition:

export type BaseSchema = {
  type?: ParameterType;
  format?: string;
  title?: string;
  description?: string;
  default?: any;
  multipleOf?: number;
  maximum?: number;
  exclusiveMaximum?: boolean;
  minimum?: number;
  exclusiveMinimum?: boolean;
  maxLength?: number;
  minLength?: number;
  pattern?: string;
  maxItems?: number;
  minItems?: number;
  uniqueItems?: boolean;
  maxProperties?: number;
  minProperties?: number;
  enum?: any[];
  items?: Schema | Schema[];
};

export interface Schema extends BaseSchema {
  $ref?: string;
  allOf?: Schema[];
  additionalProperties?: Schema | boolean;
  properties?: { [propertyName: string]: Schema };
  discriminator?: string;
  readOnly?: boolean;
  xml?: XML;
  externalDocs?: ExternalDocs;
  example?: any;
  required?: string[];
}

fastify.register(swagger, {
  routePrefix: '/documentation',
  swagger: {
    info: {
      title: 'Test swagger',
      description: 'testing the fastify swagger api',
      version: '0.1.0',
    },
    externalDocs: {
      url: 'https://swagger.io',
      description: 'Find more info here',
    },
    host: 'localhost',
    schemes: ['http'],
    consumes: ['application/json'],
    produces: ['application/json'],
    tags: [
      { name: 'user', description: 'User related end-points' },
      { name: 'code', description: 'Code related end-points' },
    ],
    definitions: {
      User: {
        type: 'object',
        required: ['id', 'email'],
        properties: {
          id: { type: 'string', format: 'uuid' },
          firstName: { type: 'string', nullable: true },
          lastName: { type: 'string', nullable: true },
          email: { type: 'string', format: 'email' },
        },
      },
    },
    securityDefinitions: {
      apiKey: {
        type: 'apiKey',
        name: 'apiKey',
        in: 'header',
      },
    },
  },
  exposeRoute: true,
})

Expected behavior

No error at all.

fastify.register(swagger, {
  routePrefix: '/documentation',
  swagger: {
    info: {
      title: 'Test swagger',
      description: 'testing the fastify swagger api',
      version: '0.1.0',
    },
    externalDocs: {
      url: 'https://swagger.io',
      description: 'Find more info here',
    },
    host: 'localhost',
    schemes: ['http'],
    consumes: ['application/json'],
    produces: ['application/json'],
    tags: [
      { name: 'user', description: 'User related end-points' },
      { name: 'code', description: 'Code related end-points' },
    ],
    definitions: {
      User: {
        type: 'object',
        required: ['id', 'email'],
        properties: {
          id: { type: 'string', format: 'uuid' },
          firstName: { type: 'string',  },
          lastName: { type: 'string',  },
          email: { type: 'string', format: 'email' },
        },
      },
    },
    securityDefinitions: {
      apiKey: {
        type: 'apiKey',
        name: 'apiKey',
        in: 'header',
      },
    },
  },
  exposeRoute: true,
})

Your Environment

• node version: 12
• fastify version: >=3.0.0
• os: macOS