lib/index.js
function (settings) {

    let out = '';
    if (settings.securityDefinitions) {
        Object.keys(settings.securityDefinitions).forEach((key) => {

            if (settings.securityDefinitions[key]['x-keyPrefix']) {
                out = settings.securityDefinitions[key]['x-keyPrefix'];
            }
        });
    }
    return out;
}
function (settings) {

    let out = '';
    if (settings.securityDefinitions) {
        Object.keys(settings.securityDefinitions).forEach((key) => {

            if (settings.securityDefinitions[key]['x-keyPrefix']) {
                out = settings.securityDefinitions[key]['x-keyPrefix'];
            }
        });
    }
    return out;
}
function ( settings ) { let out = '' ; if ( settings . securityDefinitions ) { Object . keys ( settings . securityDefinitions ) . forEach ( ( key ) => { if ( settings . securityDefinitions [ key ] [ 'x-keyPrefix' ] ) { out = settings . securityDefinitions [ key ] [ 'x-keyPrefix' ] ; } } ) ; } return out ; }
finds any keyPrefix in securityDefinitions - also add x- to name

@param  {Object} settings
@return {String}
finds any keyPrefix in securityDefinitions - also add x - to name