QL Client (Node)

Simple streaming client for Trino built to handle large result sets with a minimal memory footprint.
This package leverages stream-json for blazing fast JSON parsing.

Installation

1) Add package to your project
``
npm install @eqworks/trino-client-node
`
or
`
yarn add @eqworks/trino-client-node
`
2) Import package into your project
`js
const { Client, PartStreamer } = require('@eqworks/trino-client-node')
`

Examples

`js
const { pipeline } = require('stream')

const { S3 } = require('aws-sdk')

const { Client, PartStreamer } = require('@eqworks/trino-client-node')

const s3Client = new S3()

// instantiate client
const client = new Client({ host: 'trino.locus.place', username: '', password: '' })

// run query
const myQuery = new Promise((resolve, reject) => {
const queryStream = client.query('SELECT * FROM some_table')

// split results into parts of ~20MB compressed and stream to S3
const parts = []
const partHandler = (partIndex, partStream) => {
parts.push(
s3Client.upload({
Bucket: 'test-kevin2',
Key: ql-trino-test/my_test/${partIndex + 1},
Body: partStream,
ContentEncoding: 'gzip',
ContentType: 'application/json'
}).promise()
)
}

pipeline(
[
queryStream,
new PartStreamer({ partSizeMB: 20, partHandler }),
],
(err) => {
if (err) {
return reject(err)
}
// resolve myQuery promise when all parts have been written to S3
Promise.all(parts).then(resolve).catch(reject)
}
)
}
``