I am still new to cache objectscript and am trying to figure out how I would go about removing the escape characters from my JSON below. When I call the $toJSON method it's adding the "\" character in the file path.



My Code:

0 11 5,815

So, one day you're working away at WidgetsDirect, the leading supplier of widget and widget accessories, when your boss asks you to develop the new customer facing portal to allow the client base to access the next generation of Widgets..... and he wants you to use Angular 1.x to read into the department's Caché server.   

There's only one problem:  You've never used Angular, and don't know how to make it talk to Caché.

This guide is going to walk through the process of setting up a full Angular stack which communicates with a Caché backend using JSON over REST.  

5 10 5,149

Hi all,

I have an incoming JSON message with a string field exceeding in length the 'caché long-string limit' of 3641144 characters.

Using {}.%FromJSON(instream) I am able to create %DynamicObject properly. However, I am unable to access the long property, as in every assignment, I get the <MAXSTRING> error.

Is there any way for me to obtain contents of the 'too long' string field as a stream?



0 3 4,781

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!

1 8 3,931
Stefan Wittmann · Aug 25, 2016
JSON changes in Caché 2016.2

As Bill has mentioned earlier in his post, we have carefully reviewed the JSON capabilities and made some adjustments to ensure they deliver the best benefit to you. In this post, I am going to describe the modifications in more detail and provide guidance for you to understand the implication for your code base.

0 8 3,257
Bapu Hirave · Mar 24, 2017
Convert to JSON string

here is my $ZV string "Cache for Windows (x86-64) 2016.2.1 (Build 803) Wed Oct 26 2016 12:43:35 EDT"

 two questions

1. How do i convert any Persistent object to JSON String ?

2. How do i convert an y Register object to JSON string ?

3. Do i need to extend from any adaptor class for 1 & 2 ?

0 11 3,023

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.

0 10 2,488
Michael Smart · Oct 7, 2016 4m read
Forwarding Requests in a REST Service

One useful feature of our REST framework is the ability for a dispatch class to identify request prefixes and forward them to another dispatch class. This approach of modularizing your URL map will improve code readability, enable you to easily maintain separate versions of an interface, and provide a means to protect API calls that only certain users will be allowed to access.

0 1 2,461


The field test of Caché 2016.2 has been available for quite some time and I would like to focus on one of the substantial features that is new in this version: the document data model. This model is a natural addition to the multiple ways we support for handling data including Objects, Tables and Multidimensional arrays. It makes the platform more flexible and suitable for even more use cases.

0 12 2,337

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.

1 13 2,265
Istvan Hahn · Sep 30, 2016 8m read
Consuming RESTful Web Services

The article is a step by step guide for beginners to learn how to build a RESTful web service consumer (or client) in Ensemble. The provider can be any RESTful service, but the example is based on the service we made during the previous sessions.

0 0 2,071

With the release of Cache 2016.1, JSON support was re-architected and made part of the core object model with the creation of %Object and %Array classes, which allow you to create dynamic JSON enabled objects and arrays.

On a recent demonstration I was working on, I had the need to create a REST web service that returned a JSON representation of a persistent object.  After searching for methods that would allow me to accomplish this, ultimately I found none, until now.

0 20 1,929

Generally speaking, InterSystems products supported dynamic objects and JSON for a long while, but version 2016.2 came with a completely new implementation of these features, and the corresponding code was moved from the ObjectScript level to the kernel/C level, which made for a substantial performance boost in these areas. This article is about innovations in the new version and the migration process (including the ways of preserving backward compatibility).

2 0 1,859
Istvan Hahn · Sep 21, 2016 7m read
REST in Pieces

A beginners guide to develop Ensemble RESTful web services.


Before you start reading this short introduction please go through the on-line documentation of Ensemble with special attention to chapter “Creating REST services and clients with Ensemble”.

The approach in the documentation is undisputable the fastest and easiest way to create RESTful services. As a beginner I went through the documentation and I had several questions. This short article is listing those questions plus my humble answers.

0 6 1,840
Istvan Hahn · Sep 23, 2016 6m read
Creating a RESTful Service using Ensemble

This is a detailed guide to develop RESTful services using InterSystems Ensemble. The goal of this guide is to make you understanding the basic concept and building blocks of a RESTful service. The service is going to provide a very basic functionality (a “Hello world!”).

You will learn how to create required components as Ensemble classes, configure the run-time as an Ensemble Production and create a service configuration as a web application.

0 1 1,818

or "So you just got yelled at by your boss, for sending him an unformatted Hello World webpage"

Our previous lesson ended with us serving a Message value obtained from a Caché REST service to the client, using Angular as a runtime.  While there is a lot of moving parts involved in this process, the page is not especially exciting at the moment.  Before we can start adding new features, we should take a step back and review our tools.

1 0 1,790
Yuriy Borokhov · Apr 1, 2017
XML to Json conversion


Are there any utilities/api in HealthConnect 2016.2.1 that will allow conversion of XML virtual document to Json format? We were thinking to convert HL7 ADT message to XML via Ensemble DTL and then send it to another BP to convert to Json format for transmission via Web Services. To my understanding there isn't anyway to represent Json as a virtual object so it can be use for direct mapping of HL7 2.x message to Json via Ensemble DTL.



0 3 1,746

Recently, a partner company started to develop an Angular client for their Cache application. Together, we decided to leverage the power of Caché dynamic objects to exchange JSON encoded data between client and server parts. However, we realized that currently there is a gap in Cache JSON implementation that prevents simple use of traditional registered and persistent classes to exposed their data with the same ease as with XML. I wrote a small JSON adapter, that does the job and bridgers the gap. It's purpose is simple expose data described by a regular Cache class in a one-to-one fashion to a %DynamicObject. On the other hand, when a serialized JSON data comes in, it can be easily deserialized into dynamic object and subsequently bound to regular class by the newly created adapter.

1 7 1,650

There are several options how to deliver user interface(UI) for DeepSee BI solutions. The most common approaches are:

  • use native DeepSee Dashboards, get web UI in Zen and deliver it in your web apps.
  • use DeepSee REST API, get and build your own UI widgets and dashboards.

The 1st approach is good because of the possibility to build BI dashboards without coding relatively fast, but you are limited with preset widgets library which is expandable but with a lot of development efforts.

The 2nd provides you the way to use any comprehensive js framework (D3, Highcharts, etc) to visualize your DeepSee data, but you need to code widgets and dashboards on your own.

Today I want to tell you about yet another approach which combines both listed above and provides Angular based web UI for DeepSee Dashboards -  DeepSee Web library.

5 16 1,501