Article
· Mar 19, 2019 9m read
A Tutorial On WebSockets

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.

9 7
3 5.4K

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.

5 12
0 3K

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.

3 0
3 1K

QEWD is assumed by most people to only integrate with IRIS (or Cache) via a connection through IRIS's high-performance C interface. This requires QEWD (and its Node.js environment) to be installed and configured on the same machine as IRIS.

I'm frequently asked if QEWD can run on a separate server (or servers), and access IRIS (or Cache) over a network connection. The answer is yes it can, but the information on how to set it up in this way has been admittedly a bit tricky to discover.

0 0
0 309

Developing a Full-Stack JavaScript web app with Caché requires you to bring together the right building blocks. Previously, I outlined the basic steps to install and connect Node.js to Caché and make it's powerful multi-model database capabilites available for use with Node.js. You can use Caché as a NoSQL-, document- (with unique key-level access!), SQL- and object-database with Node.js. When developing JavaScript applications, you'll see how powerful this combination is and makes Caché a perfect fit for Node.js.

In the first part of this article series I will show how to get started with the React framework, one of the most popular frameworks currently taking over front-end development. In the next parts you'll learn how to connect a basic web app to a Caché back-end.

You'll see, it's very easy to get started with this technology - you can even compare the amount of basic knowledge you need to COS because you only need to know a few basic concepts to start!

9 8
1 4.7K

Those of you who are following the FullStack competition here in the Developer Community will know that I submitted an entry named qewd-conduit. I wanted to summarise why I think it's something worth you taking a bit of time to check out.

qewd-conduit uses the Node.js-based QEWD framework alongside IRIS to implement the back-end REST APIs for something known as the RealWorld Conduit application:

https://github.com/gothinkster/realworld

5 6
1 433

Some time ago I got a WRC case transferred where a customer asks for the availability of a raw DEFLATE compression/decompression function built-in Caché.

When we talk about DEFLATE we need to talk about Zlib as well, since Zlib is the de-facto standard free compression/decompression library developed in the mid-90s.

Zlib works on particular DEFLATE compression/decompression algorithm and the idea of encapsulation within a wrapper (gzip, zlib, etc.).
https://en.wikipedia.org/wiki/Zlib

9 6
1 2.5K

Full-Stack JavaScript development allows you to create state-of-the-art applications with Caché. With any (web) app you build nowadays, one has to make a lot of architectural decisions and you want to make the right ones. With the Node.js connector available for Caché, you can create a very powerful server side application server, allowing you to use the latest JavaScript technology and frameworks client- and server-side.

With all these new technologies, the most important is to integrate them in the most efficient way and to create a very productive development experience. This article willl get you started step-by-step with Node.js technology.

9 13
1 3K

Hi Developers!

This is the second post on the resources for Developers. This part is about Open Exchange

Using Open Exchange to Learn InterSystems

InterSystems Open Exchange is a applications gallery of tools, connectors, and libraries which InterSystems Developers submit to share the experience, approaches and do business. All the applications are either built with InterSystems data platforms or are intended to use for development with InterSystems data platforms.

If you are a beginner developer you can take a look at applications in Technology Example category. All the applications in this category come with open source code repositories, so you are able to run the samples and examples in a docker container with IRIS on your laptop or in the cloud IRIS sandbox. Examples:

0 0
0 319

In this article I'll describe how to set up web services and/or REST services using EWD 3.

Since EWD 3 is designed to be modular, you can construct the environment that exactly meets your needs, but for much of the time you'll probably find that the pre-built EWD 3 ewd-xpress super-module does most of what you need because it hooks together all the core EWD 3 and other building-blocks you'll need:

4 1
1 1.3K
Article
· Feb 8, 2019 2m read
Client Websockets based on Node.js

It will demonstrate the wide range that is openend by making use
of the power embedded in Node.js and its adapter to Caché, Ensemble, Health,..*
Node / JavaScript have wide reputation to work as a WebSocket client.
By using the Caché adapter it becomes easy to control it and to consume the results as a
Client for WebSocket Servers and to collect the replies in Caché, Ensemble, ..

I used node-v6.16.0-x64.msi and cache610.node as cache.node

You provide a Global for input:

14 0
1 787

There's a new and exciting enhancement to QEWD that has just been released - it's an additional layer of abstraction known as QEWD-Up. QEWD-Up hides away all the mechanics of QEWD itself, allowing you to focus on just your REST APIs and the code that implements them.

Additionally, and importantly, QEWD-Up simplifies the maintenance of your REST APIs, allowing you (and others) to quickly and easily understand their life-cycle and implementation.

3 3
4 765

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:

5 3
7 862

If your looking to develop a Node.JS to Caché library then you might want to consider using a pure TCP connection with a custom message transport protocol. This bypasses the native Caché connector libraries that can get stale with a new release.

Node.JS is very good at non blocking code development, so building a performant solution isn't that complex.

5 0
2 772

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.

3 0
0 2K
Article
· Apr 18, 2017 1m read
Having your Node.js Cake and Eating It Too

I've mentioned the QEWD project in this group before: it's a Node.js-based platform for web, Native and REST applications which tightly integrates with Cache. It uses a somewhat different philosophy to the use of Node.js than the norm, and I've now published an article that explains this approach and the unique benefits that arise as a result.

It turns out that, integrated via QEWD, Cache is an ideal bed-fellow for Node.js. QEWD makes the integration of Cache and Node.js exceptionally fast, simple and intuitive to use, but also extremely powerful.

Read the article here:

4 4
0 517
Article
· Jul 31, 2017 5m read
Introduction to QEWD Micro-Services

In my previous posting about the new support in QEWD for JSON Web Token (JWT) support, I mentioned that it was a key step in enabling Micro-Service support in QEWD. In this post I'll give some background to how they work and the thinking behind them.

If you haven't heard about Micro-Services and/or want to learn more, there's lots of information available if you do a Google Search. Here's a good starting point:

https://smartbear.com/learn/api-design/what-are-microservices/

3 3
0 666

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.

14 10
0 2.3K