[рони]

NovichokJS,

const createLogger = () => {
    let type = '';
    let message = '';
    let arr = [];

    function warn(messageOfWarn) {
        type = 'warn';
        message = messageOfWarn;
        arr.push({type, message})
    }

    function error(messageOfError) {
        type = 'error';
        message = messageOfError;
        arr.push({type, message})
    }

    function log(messageOfLog) {
        type = 'log';
        message = messageOfLog;
        arr.push({type, message})
    }

    function getRecords(type) {
        let a = arr.filter(({type : e}) => e == type);
        a = a.map(o => (o.dateTime = new Date(), o));
        return a;
    }
    return {
        warn,
        error,
        log,
        getRecords,
    }
};

// examples
const logger1 = createLogger();
logger1.log('User logged in');
logger1.warn('User is tring to ented restricted page');
logger1.log('User logged out');
logger1.error('Unexpected error on the site');
console.log(logger1.getRecords('log')); // ===> [{ message: 'User logged out', type: 'log', dateTime: Date }, { message: 'User logged in', type: 'log', dateTime: Date }]