ad-promise/lib/services/internal/service.truncateLogOutput.js

This is a fork of the gheeres node-activedirectory. It fixes some issues with timeouts with very large AD-Groups as well as returning also promises so you won't have to use callbacks

const maxOutputLength   = 256;

const truncateLogOutput = (output, maxLength) => {
    if (typeof (maxLength) === 'undefined') maxLength = maxOutputLength;
    if (!output) return (output);

    if (typeof (output) !== 'string') output = output.toString();
    var length = output.length;
    if ((!length) || (length < (maxLength + 3))) return (output);

    var prefix = Math.ceil((maxLength - 3) / 2);
    var suffix = Math.floor((maxLength - 3) / 2);
    return (output.slice(0, prefix) + '...' +
        output.slice(length - suffix));
}

module.exports = truncateLogOutput;