AWS Lambda“在完成请求之前已退出流程”

Question

在完成请求错误之前退出的进程是随机同意的。 起初我得到了结果，但几分钟后，它就抛出了  这是我使用的代码。

/*function name : parkinfo*/

var AWS = require('aws-sdk');

var mysql = require('mysql');

var connection;


exports.connectWkDatabase = function (event, callback) {

    var hostName = event['stage-variables']['dbhost'];
    var userName = event['stage-variables']['dbusername'];
    var dbPassword = event['stage-variables']['dbpassword'];
    var databaseName = event['stage-variables']['dbname'];
    var dbPort = event['stage-variables']['dbport'];
    connection = mysql.createConnection({
        host: hostName,
        user: userName,
        password: dbPassword,
        database: databaseName,
        port: dbPort,
        debug: false
    });

    connection.connect(function (err) {
        if (err) console.log(err);
        else {
            console.log('db connected');
        };
    });

    callback({ 'status': 'OK' });
};


exports.getParkinfo = function (event, callback) {

    if (event['params']['querystring']['keepersScheduleId'])
 {

 var sql = "select p.parkImage,p.parkTitle,p.parkingAvailable,p.parkNoOfPlace,s.toTime,u.user_nom,p.parkAddress,p.parkLandmark,p.shelter from keepersSchedule k left outer join parkDetails p on k.parkIdFk = p.parkId left outer join user_details u on k.keeperIdFk = u.userid left outer join shiftMaster s on s.shiftMasterId = k.shiftMasterIdFk where k.keepersScheduleId = '" + event['params']['querystring']['keepersScheduleId'] + "'";

        connection.query(sql, function (err, result) {
            if (err) {
                var response = {
                    "status": "ERROR",
                    "statusCode": "201",
                    "message": "Fail to execute the query",
                    "data": result
                }
                callback(response);
            }
            else {
                if (result.length > 0) {
                    var message = 'vote mastere details retrived successfully !';
                    var status = 'OK';
                    var statusCode = '200';
                } else {
                    var message = 'requested vote mastere details not found';
                    var status = 'ERROR';
                    var statusCode = '201';

                }
                var response = {
                    "status": status,
                    "statusCode": statusCode,
                    "message": message,
                    "data": result
                }
                callback(response);
            }
        });

    }
    else {
        var response = {
            "status": "ERROR",
            "statusCode": "201",
            "message": "Schedule id missing",
            "data": result
        }
        callback(response);
    }
};


exports.closeDbConnection = function (event, callback) {

    connection.end();

    callback({ 'status': 'OK' });

};

exports.handler = function (event, context) {

    exports.connectWkDatabase(event, function (res) {
        var httpMethod = event['context']['http-method'];
        var postData = event['body-json'];
        if (httpMethod == 'GET') {
        exports.getParkinfo(event, function (outputResponse) {
            exports.closeDbConnection(event, function (res) {
                console.log(outputResponse);
                    context.done(null, outputResponse);
                });
            });
        }
    });
};