Promise-MySQL无法将连接释放回池 [英] Promise-MySQL cannot release connections back to the pool

问题描述

我对Node.js开发非常陌生，我正在开发一个需要我从mysql数据库中拉用户的应用程序.我正在使用promise-mysql库查询mysql数据库.我正在尝试使用这样的连接池:

I am very new to Node.js development and I am working on an app that requires me to pull users from a mysql database. I am using the promise-mysql library to query a mysql database. I am trying to use a connection pool like this:

var pool = mysql.createPool({
  host:     hgh.host,
  user:     hgh.user,
  password: hgh.pw,
  database: hgh.name,
  connectionLimit: 10
});

作为模块中的全局变量.

As a global variable in my module.

然后我具有以上功能，可以从池中返回连接.

I then have the above function to return a connection from the pool.

function connect() {
  return pool.getConnection().then(function(connection) {
    return connection
  }).catch(function(error) {
    console.log("Connect failed");
    throw ErrorModel.generateErrorObject(error, 500);
  });
}

下面是我用来查询数据库的函数:

Below is a function I am using to query the database with:

function getUser(username) {
  var sql_query = `SELECT * FROM userstable WHERE userName = ` + `'` + username + `'`;
  return connect().then(function(conn) {
    return conn.query(sql_query).then(function(rows) {
      console.log("HGH getUser Then");
      console.log(pool);
      conn.release();
      return rows;
    });
  }).catch(function(error) {
      console.log("HGH getUser Catch");
      console.log(error);
      throw ErrorModel.generateErrorObject(error, 500);
  });
}

我遇到了这个问题:

conn.release在尝试将我当前的连接释放到池中时不起作用.我的逻辑在这里错了吗?我的目标是建立一个带有一堆连接的池(最多一定数量)，如果用户需要查询，getConnection()函数只是从池中获取它们的免费连接，或者创建一个连接.问题是我无法终生将其作为free释放回池中.每次我使用conn.end()而不是release发出请求时，连接都保留在池的_allConnections数组中对其进行控制，并且_freeConnections数组中绝对没有连接.

conn.release is not a function when trying to release my current connection into the pool. Is my logic wrong here? My goal is to have a pool with a bunch of connections (up to a certain number) and if a user needs to query, the getConnection() function just grabs them either a free connection from the pool, or creates them one. Problem is I cannot for the life of me release it back to the pool as free..Every time I make a request with conn.end() instead of release the connection remains in the _allConnections array of the pool when I console it out, and there are absolutely no connections in the _freeConnections array.

任何人都知道如何使连接再次免费?

Anyone know how I can make connections free again??

推荐答案

通过查看模块代码，我发现了从池中释放连接的功能:

Looking at the module's code I found the function for releasing a connection from a pool:

pool.prototype.releaseConnection = function releaseConnection(connection) {
    //Use the underlying connection from the mysql-module here:
    return this.pool.releaseConnection(connection.connection);
};

因此，如果所有这些功能都位于同一个文件中，则可以在getUser函数中执行以下操作: 替换

So if all of these functions live in the same file you could do the following in the getUser function: replace

conn.release();

使用

pool.releaseConnection(conn);

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