异步函数像同步一样工作

Question

我会尽量简单，当我想在函数 (SetLogs) 中执行异步查询时，我会在所有调用结束时在日志中看到我的 console.log('query 1 log')，而不是看到他在 console.log('start log '); 和 console.log('return pool logs'); 之间，我有 2 个部分：

我的主打

logs.SetLogs(pool, req, res).then(bResultLog=> {
    console.log('return pool logs');
})

console.log("END")
return pool

设置日志函数：

static async SetLogs(pool, req, res) {
  
    var now = new Date();
    var endpoint = req.originalUrl.split("?")[0].replace("/", "")

    var query = "INSERT INTO LOGS_PORTAIL (ENDPOINT, TYPE, DATE_HEURE_LOGS, LOGIN) VALUE ('" + endpoint + "','" + req.method + "','" + now.toISOString().slice(0, 19).replace('T', ' ') + "','" + 'API' + "')";
    
    console.log('start log ');
    
    pool.query(query, function(err, results) {
        console.log('query 1 log ');
        return true
    });
    
    console.log('fin log ');

}

这是我的日志:

start log
fin log
END
return pool logs
query 1 log

Answer 1

正如我上面所说，你缺少await、https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await

async function SetLogs() {
 
    var now = new Date();
    console.log('start log');
    
    var res = await queryTest();
    console.log(res);
    console.log('fin log');
}

function queryTest() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve('foo');
    }, 300);
  });
}

SetLogs();

异步函数像同步一样工作

asynchronous function work like synchronous

javascript

asynchronous

callback