nodejs记录日志信息

const fs = require('fs');
const path = require('path');
function Log(err,info) {
    let errorLog;
    if (err){
        util.error(err);
        errorLog= fs.createWriteStream(path.join(__dirname,'/../error.log'),{flag:'a'});
        let meta = '['+new Date()+'] '+ '\n';
        let msg = JSON.stringify(info);
        let errMsg = err.stack.toString();
        errorLog.write(meta+ msg +'\n' + errMsg+'\n');
    }else{
        errorLog = fs.createWriteStream(path.join(__dirname,'/../info.log'),{flag:'a'});
        let meta = '['+new Date()+'] '+ '\n';
        let msg = {};
        if(info.length > 1){
            info.forEach(function (ret,index) {
                msg['result'+index] = ret;
            }) ;
        }else{
            msg['result'] = info;
        }

        msg = JSON.stringify(msg);
        errorLog.write(meta+ msg +'\n');
    }
    if(errorLog){
        errorLog.end('------------------------log ---------------------');
    }
}