Uncaught exception in pool.query

[thorbenziemek]

Uncaught exception in pool.query

[thorbenziemek]

I don't know if this really makes it clearer, but to simulate the uncaughtException, this could be used as the query function (throws an arbitrary error - if we keep the throw, it will lead to an uncaughtException, regardless of whether the connection has an error handler registered):

...
query(sql, values, cb) {
    const cmdQuery = Connection.createQuery(
      sql,
      values,
      cb,
      this.config.connectionConfig
    );
    if (typeof cmdQuery.namedPlaceholders === 'undefined') {
      cmdQuery.namedPlaceholders = this.config.connectionConfig.namedPlaceholders;
    }
    this.getConnection((err, conn) => {
      if (err) {
        if (typeof cmdQuery.onResult === 'function') {
          cmdQuery.onResult(err);
        } else {
          cmdQuery.emit('error', err);
        }
        return;
      }
      try {
        // XXXXXX THROW ERROR for demo
        throw new Error("Simulated error.");
        conn.query(cmdQuery).once('end', () => {
          conn.release();
        });
      } catch (e) {
        conn.release();
        
        // if we keep throw e; here, this will raise an uncaughtException:
        // throw e;

        // XXXXXX SEND ERROR TO CALLBACK INSTEAD OF throw
        const actualCb = cb || values; // values is optional
        actualCb(e);
        // XXXXXX
      }
    });
    return cmdQuery;
  }
...

[thorbenziemek]

fyi, I'm not so sure whether the calling the callback with the error really is what is desired in terms of "throwing if no one listens any more" etc. Currently I use this workaround (I'm using the promise wrapper):

    async queryPool(query: string, values?: any) {
        const conn = await pool.getConnection();
        try {
            const result = await conn.query(query, values);
            return result;
        } finally {
            conn.release();
        }
    }

I can live with this workaround for now.