Promise with node-postgres queries always returns undefined

Question

我在评估使用 node-postgres 查询的函数的结果时遇到问题，它总是 return“未定义”（此函数验证 JWT 令牌信息在数据库中的有效性）：

const testTokenQuery = function(account_id, is_admin, query) {
  return new Promise(function(resolve, reject){
    pool.query(query, [account_id], function(err, result) {
        if(err) {
          reject("invalid")
        }
        else {
          const bdd_account_id = String(JSON.stringify(result.rows[0].ac_account_id)).replace(/['"]+/g, '')
          const bdd_is_admin = String(JSON.stringify(result.rows[0].ac_isadmin)).replace(/['"]+/g, '')
          if (account_id == bdd_account_id || tok_is_admin == bdd_is_admin){
            resolve ("valid")
          }
          else {
            reject("invalid")
          }

        }
    })
    pool.end();
  })
}

const testToken = (token) => {
  const checkTokenId_query = sql = fs.readFileSync('./sqlqueries/checkTokenId_query.sql').toString()
  const decodedToken = jwt.decode(token, 'JWT_SIGN_SECRET')
  const tok_account_id = decodedToken.account_id
  const tok_is_admin = decodedToken.isadmin
  testTokenQuery(tok_account_id, tok_is_admin, checkTokenId_query)
    .then(function(result){
      console.log(result) //===================> It allways return the good value here
  }).catch(function(err){
    console.log(err);   
  })
}


const isvalid = testToken('eyJhbGciO............ltJT0PhXCjV00')
if(isvalid == "valid") {
  console.log("valid token")
}
else if(isvalid == "invalid") {
  console.log("not a valid token")
}
else{
  console.log("I don't know : " + isvalid) //======> Always the result with isvalid = undefined
}

SQL 查询文件包含：

SELECT  ac_account_id,
            ac_isadmin,
            ac_isactive
FROM    table_accounts
WHERE ac_account_id = ;

结果总是“我不知道：未定义”，而 testTokenQuery 的 console.log（结果）。然后 returns“有效”...

我测试了回调：同样的问题，await/async：同样的问题...我要疯了...

感谢您的帮助！

此致。

更新：我试图在极端情况下简化以使用异步进行测试，但我仍然有“未定义”作为答案：

const testTokenQuery = async (account_id, query) => {
    pool.query(query, [account_id], function(err, result) {
      return String(JSON.stringify(result.rows[0].ac_account_id))
    })
}
const testToken = async (token) => {
    const checkTokenId_query = sql = fs.readFileSync('./sqlqueries/checkTokenId_query.sql').toString()
    const decodedToken = jwt.decode(token, 'JWT_SIGN_SECRET')
    const tok_account_id = decodedToken.account_id
    return await testTokenQuery(tok_account_id, checkTokenId_query)
}

const tokenReturn = async (token) => {
    console.log(await testToken(token))
}

tokenReturn('eyJhbGciOiJ...........0PhXCjV00')

Answer 1

老实说，我以前没有使用过“node-query”，但我刚刚探索过this issue talk（这是关于 .end() 的，所以我认为这不是问题）。

从你的代码来看，我认为原因是你调用了函数本身，而不是回调（不是解析的）结果。我认为您可以使用 async-await 来实现它。这不是完整的代码。在最后一部分中，我需要调用异步函数，所以我使用作用域函数来实现，但您可以根据需要进行更改。

尝试这样的事情：

const testTokenQuery = async (account_id, is_admin, query) => {
    pool.query(query, [account_id], function(err, result) {
        if(err) {
            return "invalid";
        } else {
            const bdd_account_id = String(JSON.stringify(result.rows[0].ac_account_id)).replace(/['"]+/g, '')
            const bdd_is_admin = String(JSON.stringify(result.rows[0].ac_isadmin)).replace(/['"]+/g, '')
            if (account_id == bdd_account_id || tok_is_admin == bdd_is_admin){
                return "valid";
            } else {
                return "invalid";
            }
        }
    });
}

const testToken = async (token) => {
    const checkTokenId_query = sql = fs.readFileSync('./sqlqueries/checkTokenId_query.sql').toString()
    const decodedToken = jwt.decode(token, 'JWT_SIGN_SECRET')
    const tok_account_id = decodedToken.account_id
    const tok_is_admin = decodedToken.isadmin
    
    return await testTokenQuery(tok_account_id, tok_is_admin, checkTokenId_query)
}

(async () => {
    const isvalid = await testToken('eyJhbGciO............ltJT0PhXCjV00')
    if(isvalid == "valid") {
        console.log("valid token")
    } else if(isvalid == "invalid") {
        console.log("not a valid token")
    } else {
        console.log("I don't know : " + isvalid) //======> Always the result with isvalid = undefined
    }
})();

Answer 2

这个函数没有return任何东西，对吧？不就是 return undefined 吗？

const testTokenQuery = async (account_id, query) => {
    pool.query(query, [account_id], function(err, result) {
      return String(JSON.stringify(result.rows[0].ac_account_id))
    })
}

这与打印 undefined.

的原因相同

const nada = (() => {})();
console.log(nada);

Promise with node-postgres queries always returns undefined

Promise with node-postgres queries always returns undefined

node.js

node-postgres