knex.on('query-error', ...) does not trigger on some connection errors

[elhigu]

Environment

Knex version: 0.16.3 Database + version: at least pg OS: probably all

Bug

1. Explain what kind of behaviour you are getting and how you think it should do

knex = require('knex')({ client : 'pg', connection: 'postgres:///invaliddb' });

// event is not triggered for connection error
knex.on('query-error', e => console.dir(e));

knex.raw('select 1').then();

2. Error message

Query rejects with some error about not being able to connect to DB.

3. Reduced test code, for example in https://npm.runkit.com/knex or if it needs real database connection to mysql or postgresql, then single file example which initializes needed data and demonstrates the problem.

Code is above.

[lfernando-silva]

it would be nice if there were a separate event to detect connection problems. But having this check would be also great.

[bordeux]

whoa, im not alone. tried to make auto-retry functionality for this....

If this not works, im going to create common retry function and scope entire query process to be retried .

[andrewkaldani30]

@bordeux Hi, having the same issue did you add some type of retry within that event listner?

[bordeux]

i crafted outside knex library. I wrapped all queries executions with retry function like

  const result = await queryRetry(knex =>  knex.raw(
      `select * from yourTable`
    );
  );
  

queryRetry function automatically catching errors, and if there is connection isssue, it repeats the query 3 times.

What exceptions im catching:

        if (
        error?.code === 'ETIMEDOUT' ||
        error?.code === 'ECONNREFUSED' ||
        error?.code === 'ER_NOT_SUPPORTED_AUTH_MODE' ||
        error?.message === 'timeout expired' ||
        error?.syscall === 'connect' ||
        error?.message?.includes('ECONNREFUSED')
      ) {
        //retry
      }