QuestDB Node.js Client

Installation

npm install @questdb/nodejs-client

Examples

Basic API usage

const { Sender } = require("@questdb/nodejs-client");

async function run() {
    // create a sender with a 4k buffer
    // it is important to size the buffer correctly so messages can fit
    const sender = new Sender({bufferSize: 4096});

    // connect to QuestDB
    // host and port are required in connect options
    await sender.connect({port: 9009, host: "localhost"});

    // add rows to the buffer of the sender
    sender.table("prices").symbol("instrument", "EURUSD")
        .floatColumn("bid", 1.0195).floatColumn("ask", 1.0221).atNow();
    sender.table("prices").symbol("instrument", "GBPUSD")
        .floatColumn("bid", 1.2076).floatColumn("ask", 1.2082).atNow();

    // flush the buffer of the sender, sending the data to QuestDB
    // the buffer is cleared after the data is sent and the sender is ready to accept new data
    await sender.flush();

    // add rows to the buffer again and send it to the server
    sender.table("prices").symbol("instrument", "EURUSD")
        .floatColumn("bid", 1.0197).floatColumn("ask", 1.0224).atNow();
    await sender.flush();

    // close the connection after all rows ingested
    await sender.close();
    return new Promise(resolve => resolve(0));
}

run().then(value => console.log(value)).catch(err => console.log(err));

Authentication and secure connection

const { Sender } = require("@questdb/nodejs-client");

async function run() {
    // construct a JsonWebKey
    const CLIENT_ID = "testapp";
    const PRIVATE_KEY = "9b9x5WhJywDEuo1KGQWSPNxtX-6X6R2BRCKhYMMY6n8";
    const PUBLIC_KEY = {
        x: "aultdA0PjhD_cWViqKKyL5chm6H1n-BiZBo_48T-uqc",
        y: "__ptaol41JWSpTTL525yVEfzmY8A6Vi_QrW1FjKcHMg"
    };
    const JWK = {
        ...PUBLIC_KEY,
        d: PRIVATE_KEY,
        kid: CLIENT_ID,
        kty: "EC",
        crv: "P-256",
    };

    // pass the JsonWebKey to the sender
    // will use it for authentication
    const sender = new Sender({bufferSize: 4096, jwk: JWK});

    // connect() takes an optional second argument
    // if 'true' passed the connection is secured with TLS encryption
    await sender.connect({port: 9009, host: "localhost"}, true);

    // send the data over the authenticated and secure connection
    sender.table("prices").symbol("instrument", "EURUSD")
        .floatColumn("bid", 1.0197).floatColumn("ask", 1.0224).atNow();
    await sender.flush();

    // close the connection after all rows ingested
    await sender.close();
    return new Promise(resolve => resolve(0));
}

run().then(value => console.log(value)).catch(err => console.log(err));

TypeScript example

import { Sender } from "@questdb/nodejs-client";

async function run(): Promise<number> {
    // construct a JsonWebKey
    const CLIENT_ID: string = "testapp";
    const PRIVATE_KEY: string = "9b9x5WhJywDEuo1KGQWSPNxtX-6X6R2BRCKhYMMY6n8";
    const PUBLIC_KEY: { x: string, y: string } = {
        x: "aultdA0PjhD_cWViqKKyL5chm6H1n-BiZBo_48T-uqc",
        y: "__ptaol41JWSpTTL525yVEfzmY8A6Vi_QrW1FjKcHMg"
    };
    const JWK: { x: string, y: string, kid: string, kty: string, d: string, crv: string } = {
        ...PUBLIC_KEY,
        d: PRIVATE_KEY,
        kid: CLIENT_ID,
        kty: "EC",
        crv: "P-256",
    };

    // pass the JsonWebKey to the sender
    // will use it for authentication
    const sender: Sender = new Sender({bufferSize: 4096, jwk: JWK});

    // connect() takes an optional second argument
    // if 'true' passed the connection is secured with TLS encryption
    await sender.connect({port: 9009, host: "localhost"}, true);

    // send the data over the authenticated and secure connection
    sender.table("prices").symbol("instrument", "EURUSD")
        .floatColumn("bid", 1.0197).floatColumn("ask", 1.0224).atNow();
    await sender.flush();

    // close the connection after all rows ingested
    await sender.close();
    return new Promise(resolve => resolve(0));
}

run().then(value => console.log(value)).catch(err => console.log(err));