lambda-stream-lib

lambda-stream-lib is JavaScript API library that allows developers to interact with a Luniverse Transaction Listener Service using as WebSocket connection.

Table of contents

• Requirements
• Installation
• Environment
  • EndPoint
• Getting Started
  • Example

Requirements

The following packages are required to use the lambda-stream-lib library.

• Node.js
• npm

Note lambda-stream-lib can run on Node.js versions 8 and 10, and the recommended versions are:

• lts/carbon (8.16.0)
• lts/dubnium (10.16.0)

If you are already using a different version of the node(for example, node v12), use the Node Version Manager(NVM) to install and use the version supported by lambda-stream-lib.

Installation

To try it out, install lambda-stream-lib with npm like following command:

$ npm install lambda-stream-lib

Note package.json file should exist on the same install path. If it does not exist, package.json should be generated via npm init.

To install a specific version of lambda-stream-lib, try the following command:

$ npm install [email protected]

Environment

EndPoint

 Production: `ws://stream.luniverse.io:80`

Getting-Started

Receive-Receipt

lambda-stream-lib is designed to be the simplest way possible to receive receipt.

const LambdaStreamClient = require('lambda-stream-lib');

    const endPoint = '#insert endPoint#';
    const lChainId = `#insert lChainId#`;
    const accessKey = '#insert streamAccessKey#';

    try {
        let streamClient = new LambdaStreamClient(endPoint, lChainId, accessKey);

        streamClient.on('RECEIPT', async function message(messages) {
            for (let message of messages) {
                console.info(JSON.stringify(message));
            }

            let lastOffset = Number(messages[messages.length - 1].data.offset) + 1;

            await streamClient.commit(lastOffset);
        });

        streamClient.on('ERROR', async function message(message) {
            console.info(JSON.stringify(message));
        });

        await streamClient.start();
    } catch (err) {
        console.error(err);
    }