redux-log-slow-reducers/lib/index.js

Warn about slow reducers used in your redux app.

/* eslint no-console:0 */

'use strict';

Object.defineProperty(exports, '__esModule', {
    value: true
});
exports['default'] = logSlowReducers;

function logSlowReducers(reducers) {
    var thresholdInMs = arguments.length <= 1 || arguments[1] === undefined ? 8 : arguments[1];

    Object.keys(reducers).forEach(function (name) {
        var originalReducer = reducers[name];
        reducers[name] = function (state, action) {
            var start = Date.now();
            var result = originalReducer(state, action);
            var diffInMs = Date.now() - start;
            if (diffInMs >= thresholdInMs) {
                console.warn('Reducer "' + name + '" took ' + diffInMs + 'ms for ' + action.type);
            }
            return result;
        };
    });
    return reducers;
}

module.exports = exports['default'];