#Node.js

Intro

Most server-client communication on the web is based on a request and response structure. The client sends a request to the server and the server responds to this request. The WebSocket protocol provides a two-way channel of communication between a server and client, allowing servers to send messages to clients without first receiving a request. For more information on the WebSocket protocol and its implementation in InterSystems IRIS, see the links below.

• WebSocket protocol

I cannot connect to Cache from node.js

I have installed in Windows 10 the following: CACHE 2016, node.js v 4.4.7 and express .

- where can I get cache.node? The link in the Intersystmes documentation http://globalsdb.org/downloads/ doesn't work. I found cache0100.node and cache0120.node in my Cache instance's \bin directory. But I am not sure if I can use them or not.

- how to install cache.node ? Where do I place it exactly?

Developing a Full-Stack JavaScript web app with Caché requires you to bring together the right building blocks. In the previous part, we created a basic front-end React application. In the second part of this article series I will show how to choose the right back-end technology for your application. You will see Caché allows you to use many different approaches to link your front-end to your Caché server, depending on your application's needs. In this part we will set up a back-end with Node.js/QEWD and CSP/REST. In the next part we will enhance our basic web app and connect it to Caché using these technologies.

ˮ This is one of my articles which was never published in English. Let's fix it!

Globals, these magic swords for storing data, have been around for a while, but not many people can use them efficiently or know about this super-weapon altogether.

If you use globals for tasks where they truly shine, the results may be amazing, either in terms of increased performance or dramatic simplification of the overall solution (1, 2).

Globals offer a special way of storing and processing data, which is completely different from SQL tables. They were first introduced in 1966 in the M(UMPS) programming language, which was initially used in medical databases. It is still used in the same way, but has also been adopted by some other industries where reliability and high performance are top priorities: finance, trading, etc.

Later M(UMPS) evolved into Caché ObjectScript (COS). COS was developed by InterSystems as a superset of M. The original language is still accepted by developers' community and alive in a few implementations. There are several signs of activity around the web: MUMPS Google group, Mumps User's group), effective ISO Standard, etc.

Modern global based DBMS supports transactions, journaling, replication, partitioning. It means that they can be used for building modern, reliable and fast distributed systems.

Globals do not restrict you to the boundaries of the relational model. They give you the freedom of creating data structures optimized for particular tasks. For many applications reasonable use of globals can be a real silver bullet offering speeds that developers of conventional relational applications can only dream of.

Globals as a method of storing data can be used in many modern programming languages, both high- and low-level. Therefore, this article will focus specifically on globals and not the language they once came from.

One of the most important features during application development is the ability to debug your code easily. Because of the asynchrnous nature, a standard Node.js application server works single-threaded by default. When you are developing applications using an IDE like Visual Studio Code, you can very easily debug your Node.js process:

First, download the free Visual Studio Code IDE (@code) and install it on your development machine.

Developing a Full-Stack JavaScript web app with Caché requires you to bring together the right building blocks. In this third part of this article series I will show how to link our React app to our three back-ends we created in part 2.

I’m excited to announce that InterSystems will be joining the open source community for InterSystems ObjectScript extension to Visual Studio Code. Early this year I posted that we were on a journey to redefine the future of our IDE strategy, and what came out of that is Visual Studio Code is the IDE that can support that future.

Those of you who keep an eye on developments in the mainstream of IT will be aware that a major upheaval has been occurring over the last 5 or so years, in which JavaScript has exploded in popularity and importance. Largely as a result of its server-side incarnation - Node.js - it has broken free of just being the scripting language that you use in web browser, to becoming the world's most popular language and enterprise technology of choice.

This is the second part of my long post about package managers in operating systems and language distributions. Now, hopefully, we have managed to convince you that convenient package manager and rich 3^rd party code repository is one key factor in establishing of a vibrant and fast growing ecosystem. (Another possible reason for ecosystem success is the consistent language design, but it will be topic for another day.)

Something that shot up the popularity stakes last week was this article on a very interesting initiative: RealWorld:

https://medium.com/@ericsimons/introducing-realworld-6016654d36b5

I decided it would be a good idea to use this as a way of creating an exemplar implementation of a RESTful back-end using QEWD against their published API (https://github.com/gothinkster/realworld/tree/master/api)

The results are here:

I wrote a step by step tutorial in the qewd-howtos repository how you can write state of the art multi-page web apps with Node.js using a QEWD-Up WebSocket/REST api back-end integrated with a mainstream web framework like NuxtJS & Vue.js.

Here I’ll walk you through the process of creating a simple Node/Express API and connect it to a InterSystems IRIS instance.

I won't go into much detail about how to work with any of the technologies I will mention in this tutorial but I will leave links, in case you want to learn more.

The objective here is to give you a practical guide on how to set up and connect a node.js back-end API to IRIS.

Before we get our hands dirty, make sure you have Node.js running on your machine. So I'll check:

As an advanced alternative for REST calls, the new vue-qewd plugin for Vue.js allows easy integration with QEWDjs using WebSockets.