// Example query
const sqlText = `SELECT CURRENT_TIMESTAMP();`

const { promisify } = require('util')
const snowflake = require('snowflake-sdk')

const connection = snowflake.createConnection(auths.snowflake)

const connectAsync = promisify(connection.connect)

try {
  await connectAsync()
} catch (err) {
  console.error('Unable to connect: ' + err.message)
}

// util.promisify requires the last argument of the function you pass to 
// it be the callback function, according to Node convention — see the docs at
// https://nodejs.org/dist/latest-v8.x/docs/api/util.html#util_util_promisify_original .
// Since Snowflake's connection.execute function accepts a single argument — 
// options, an object — using promisify won't work. So we wrap the callback 
// with a Promise and await it below.
//
// Pass the same options object (e.g. sqlText, binds), _except_ for the callback
// parameter. Instead, you'll want to await the result, which contains the 
// stmt and rows object the callback version of the function passes, using 
// a catch block to catch any errors, e.g.
//
//   try {
//     const { stmt, rows } = await connExecuteAsync({
//       sqlText: `insert into your_table select parse_json('{"foo": "bar"}')`,
//     })
//   } catch (err) {
//     console.error(`Failed to execute statement due to the following error: ${err.message}`)
//   }
//
async function connExecuteAsync(options) {
  return new Promise((resolve, reject) => {
    const statement = connection.execute({
      ...options,
      complete: function(err, stmt, rows) {
        if (err) {
          reject(err)
        } else {
          resolve({stmt, rows})
        }
      }
    })
  })
}

try {
  const { stmt, rows } = await connExecuteAsync({
    sqlText,
    fetchAsString: ['Number', 'Date'],
  })
  console.log(JSON.stringify(rows, null, 2))
} catch (err) {
  console.error(`Failed to execute statement due to the following error: ${err.message}`)
}