Advanced HLL - Introduction

Our A-HLL API engine is made on latest technology trends enabling many new features compared to classic approach. For this reason we give our HLL engine prefix Advanced.

Why it is advanced?

Instead of classic approach by using DLL libs and native OS dependencies, we use WebSocket service embedded into our Green Screens Native Terminal enabling full duplex communication between active terminal session and connected client.

For communication widely known JSON format is used instead of complex and cryptic API's making integration much easier. Using JSON opens the doors for a new way of terminal integration possibilities.

Green Screens Web Terminal can be integrated inside web application giving programmable access to active session from hosting web page. For example, it is possible to integrate web form fill with data from terminal just with pure JavaScript etc.

It is very easy to use Node.JS runtime engine to create scriptable integration or utilities for screen scraping and many more.

We have just scratched the surface of new possibilities available through Advanced HLL API. Take this as an introduction for incoming blog posts with tips & tricks and tutorials which will show you what is possible to achieve with GreenScreens A-HLL API.

Don't talk, show me

Today we will show you how to prepare testing playground where one can check out the basics of A-HLL API.

• Install Smart WebSocket Client from Chrome Web Store
  
  
  

• Start GreenScreens Native Terminal and connect to your system

• Open Smart WebSocket Client, enter ws://localhost:5250/ in address bar then click Connect

• When connected to GreenScreens Native Terminal copy and paste following JSON instruction into first text box and click Send

  { "cmd": "queryInstances", "rid":1}

• You should see response from GreenScreens Native Terminal

This simple Quick start demo is pure web browser WebSocket API demonstration where we made connection to active terminal session to get some information. The same is possible from Node.JS or any web page.

Let's play with basic API'

Open this link to view base API functions that can be used to play and learn with Smart WebSocket Client and GreenScreens Native Terminal.