export interface RequestMetadata { 'x-goog-iam-authority-selector' : string ; 'x-goog-iam-authorization-token' : string ; } export class IAMAuth { param selector param token constructor constructor ( public selector , public token ) { this . selector = selector ; this . token = token ; } /**
     * Acquire the HTTP headers required to make an authenticated request.
     */ getRequestHeaders ( ) { return { 'x-goog-iam-authority-selector' : this . selector , 'x-goog-iam-authorization-token' : this . token , } ; } }