A console logger with name prefix and persisted enable/disable functionality.

Logger.js

/**
 * A console logger with name prefix and persisted enable/disable functionality.
 * Disabled by default.
 * Enabled/disabled state is persisted in browser storage, e.g. localStorage or sessionStorage, and survives page refresh.
 * @example:
 * this.logger = new Logger({name: 'Grid'}); this.logger.log('Yay!');
 */
function Logger(options) {
    options = options || {};
    var name = options.name || 'default';
    var lsKey = 'Logger.' + name + '.enabled';
    var storage = options.storage || window.localStorage;
    var enabled = storage.getItem != undefined && !!storage.getItem(lsKey);
    var consolefn = function (fn, args) {
        if (enabled) {
            console[fn].apply(console, ['[' + name + ']'].concat([].slice.call(args)));
        }
    };
    this.enable = function () {
        enabled = true;
        storage.setItem(lsKey, true);
    };
    this.disable = function () {
        enabled = false;
        storage.removeItem(lsKey);
    };
    this.log = function () {
        consolefn('log', arguments);
    };
    this.warn = function () {
        consolefn('warn', arguments);
    };
}