node.js异常处理_node.js怎么处理代码异常

var log4js = require('log4js');
log4js.configure({
    appenders: [
        { type: 'console' },
        { type: 'file', filename: 'd:/logs/my-app.log', category: 'my-app' }
    ]
});
var log = log4js.getLogger('my-app');
log.setLevel('INFO');

/// catch 404 and forwarding to error handler
app.use(function(req, res, next) {
    log.error("==========404===============");
    var err = new Error('Not Found');
    err.status = 404;
    next(err);
});

/// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
    app.use(function(err, req, res, next) {
        log.error("开发环境==========="+err);
        res.status(err.status || 500);
        res.render('error', {
            message: err.message,
            error: err
        });
    });
} // edit: www.jb200.com

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
    log.error("生产环境==========="+err);
    res.status(err.status || 500);
    res.render('error', {
        message: err.message,
        error: {}
    });
});
/*process.on('uncaughtException', function(err) {
    log.error("uncaughtException==========="+err);
});*/