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mysqlnode.jsdbconnection

nodejs mysql Error: Connection lost The server closed the connection


when I use node mysql, an error is appear between 12:00 to 2:00 that the TCP connection is shutdown by the server. This is the full message:

Error: Connection lost: The server closed the connection.
at Protocol.end (/opt/node-v0.10.20-linux-x64/IM/node_modules/mysql/lib/protocol/Protocol.js:73:13)
at Socket.onend (stream.js:79:10)
at Socket.EventEmitter.emit (events.js:117:20)
at _stream_readable.js:920:16
at process._tickCallback (node.js:415:13)

There is the solution. However, after I try by this way, the problem also appear. now I do not know how to do. Does anyone meet this problem?

Here is the way I wrote follow the solution:

    var handleKFDisconnect = function() {
    kfdb.on('error', function(err) {
        if (!err.fatal) {
            return;
        }
        if (err.code !== 'PROTOCOL_CONNECTION_LOST') {
            console.log("PROTOCOL_CONNECTION_LOST");
            throw err;
        }
        log.error("The database is error:" + err.stack);

        kfdb = mysql.createConnection(kf_config);

        console.log("kfid");

        console.log(kfdb);
        handleKFDisconnect();
    });
   };
   handleKFDisconnect();

Solution

  • Try to use this code to handle server disconnect:

    var db_config = {
      host: 'localhost',
        user: 'root',
        password: '',
        database: 'example'
    };
    
    var connection;
    
    function handleDisconnect() {
      connection = mysql.createConnection(db_config); // Recreate the connection, since
                                                      // the old one cannot be reused.
    
      connection.connect(function(err) {              // The server is either down
        if(err) {                                     // or restarting (takes a while sometimes).
          console.log('error when connecting to db:', err);
          setTimeout(handleDisconnect, 2000); // We introduce a delay before attempting to reconnect,
        }                                     // to avoid a hot loop, and to allow our node script to
      });                                     // process asynchronous requests in the meantime.
                                              // If you're also serving http, display a 503 error.
      connection.on('error', function(err) {
        console.log('db error', err);
        if(err.code === 'PROTOCOL_CONNECTION_LOST') { // Connection to the MySQL server is usually
          handleDisconnect();                         // lost due to either server restart, or a
        } else {                                      // connnection idle timeout (the wait_timeout
          throw err;                                  // server variable configures this)
        }
      });
    }
    
    handleDisconnect();
    

    In your code i am missing the parts after connection = mysql.createConnection(db_config);