Reconnection after connection lost

[ubuntutest]

Hi, congratulations for this module, I use it in production on my platform.

I use pm2 as a process manager.

Sometimes I get the following error:

{ Error: Connection lost: The server closed the connection.
    at Protocol.end (/home/imroot/node_modules/mysql/lib/protocol/Protocol.js:112:13)
    at Socket.<anonymous> (/home/imroot/node_modules/mysql/lib/Connection.js:94:28)
    at Socket.<anonymous> (/home/imroot/node_modules/mysql/lib/Connection.js:526:10)
    at Socket.emit (events.js:203:15)
    at endReadableNT (_stream_readable.js:1145:12)
    at process._tickCallback (internal/process/next_tick.js:63:19) fatal: true, code: 'PROTOCOL_CONNECTION_LOST' }

I think it's because my app occasionally disconnects from the database.

I found this and much more, but I'm not sure how to adapt it to your model with this different syntax, could you help me out? it could be useful for many.

Thanks

[brijeshpant83]

seems I am having same problem, sometime its get disconnected and unable to reconnect. pls suggest.

[edilsonlm217]

I'm also getting an error like that. I'm watching for those database events to notify users and at some point it stops working.

[8secz-johndpope]

I will detail some designs - but I've introduced a health check in another process that causes a restart on pm2 if the service fails.
// var mysqlPool = mysql.createPool(config.db);
var connection = mysql.createConnection(config.db);

async function getConnection() {
await new Promise ( resolve => mysqlPool.getConnection( async (err, connection) => {
if(err){
if (err.code === 'PROTOCOL_CONNECTION_LOST') {
console.error('👺 Database connection was closed.')
}
if (err.code === 'ER_CON_COUNT_ERROR') {
console.error('👺 Database has too many connections.')
}
if (err.code === 'ECONNREFUSED') {
console.error('👺 Database connection was refused.')
}
console.error('👺 mysqlPool.getConnection: ', new Date(), JSON.stringify(err))
// await this.getConnection()
} else {
console.log('🎃 connected connection:',connection)
connection = connection
resolve()
}
}))
}

[muriloneo]

does anyone has found a way to keep connected ? I have a problem that the connection can break on the middle of a processing that is activated by a insert trigger.

[8secz-johndpope]

I use dynamodb to pick up from the last known rowid / timestamp that's been processed.
https://gist.github.com/8secz-johndpope/4bf52a0d40071bfa75bfea35aea7f5b9
On reconnect - I just flash forward through transactions....