How to access knex query results

Question

Using knex with express, how can I access the results of a knex query?

Example:

var bots = []

response = knex.select('id', 'name').from('robots')
  .then(function(robots){
    console.log(robots);
    bots = robots
  });

console.log(bots)

This will log the robots but not not update the bots array, which is empty.

EDIT:

As a synchronous workaround, in an express route, I stuck the express block inside the knex block:

router.get('/robots', function (req, res) {

  response = knex.select('id', 'name').from('robots').then(function(bots){

    res.render('robots/index', {
      page_title: 'All Robots',
      robots: bots
    }); // res.render

  }); // knex.select

}); // router.get

Is this the recommended pattern?

Answer 1

knex uses Promises. Specifically, it uses http://bluebirdjs.com/docs/getting-started.html. console.log(bots) will not work because it is called right away, while .then( ... ) is only called after the knex query has been successfully called and run.

Your edited, "synchronous workaround" is the correct method to run the Express response, though you do not need to set that query to var response (see my comment on your question for more on that).

Answer 2

I'd suggest using async/await functions. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/async_function

router.get('/robots', async function (req, res) {
  const bots = await knex.select('id', 'name').from('robots');
  res.render('robots/index', {
    page_title: 'All Robots',
    robots: bots
  }); // res.render 
}); // router.get