@barchart/marketdata-api-js/README.md

SDK for streaming market data from Barchart.com

# @barchart/marketdata-api-js

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### Overview

[Barchart](https://www.barchart.com) offers streaming market data for a wide range of asset classes which trade on exchanges around the world. Review our [market data catalog](https://www.barchart.com/solutions/data/market) for details.

**This SDK enables your applications to consume real-time market data**, as follows:

* A WebSocket connection is established between your application and Barchart's quote servers, then
* Your application requests market data for one or more symbols, then
* Your application receives a market data stream for subscribed symbols.

### Openfeed

This library receives market data using a proprietary protocol called DDF. For new development, Barchart has switched to an open-source protocol called [Openfeed](https://docs.barchart.com/openfeed/#/) to transfer market data. Consequently, this library will be marked as deprecated in the near future. You can access new SDK libraries for Openfeed [here](https://www.barchart.com/solutions/services/stream).

### Documentation

Complete documentation for this SDK can be accessed here:

* [https://barchart.github.io/marketdata-api-js/#/](https://barchart.github.io/marketdata-api-js/#/)

### Demos

Working demos are available for web browser and Node.js environments. Please refer to the [documentation](https://barchart.github.io/marketdata-api-js/#/content/quick_start?id=demos).

### Package Managers

This library has been published to NPM as [@barchart/marketdata-api-js](https://www.npmjs.com/package/@barchart/marketdata-api-js). Install as follows:

 ```sh
 npm install @barchart/marketdata-api-js -S
```

### Build

Source code is written in [ES2018](https://en.wikipedia.org/wiki/ECMAScript#9th_Edition_%E2%80%93_ECMAScript_2018). Consequently, transpilation is recommended for use in web browsers.