Robert Cemper · Jun 10, 2019 1m read
A more useFull Object Dump

During testing your code you are often confronted with the need to examine
the actual content of an object. Either using ZWRITE or $system.OBJ.Dump()
you get a picture of simple properties as "--- attribute values ---"
while "--- swizzled references ---" are more confusing than informative
and with "--- calculated references ---" you are just left in the lurch.

16 0
1 763
Robert Cemper · Jul 21, 2020 2m read
Un-Typical persistence
This is a coding example working on Caché 2018.1.3 and IRIS 2020.2 
It will not be kept in sync with new versions 
It is also NOT serviced by InterSystems Support !

During my search for a snapshot of a persistent object,
I met a feature that I would like tho share as it could be useful in some special situations.
My trigger was to have a before- and an after-image during unit testing.

13 4
4 449

It is with great pleasure that the CIUSSS de l'Estrie - CHUS is sharing the mocking framework it developed and presented at the InterSystems Summit 2017. I will update this post with more detailed instructions in the next few weeks but I wanted to share the code and presentation quickly :

11 13
0 1,650

Astronomers’ tools

5 years ago, on December 19, 2013, the ESA launched an orbital telescope called Gaia. Learn more about the Gaia mission on the official website of the European Space Agency or in the article by Vitaly Egorov (Billion pixels for a billion stars).

However, few people know what technology the agency chose for storing and processing the data collected by Gaia. Two years before the launch, in 2011, the developers were considering a number of candidates (see “Astrostatistics and Data Mining” by Luis Manuel Sarro, Laurent Eyer, William O’Mullane, Joris De Ridder, pp. 111-112):

Comparing the technologies side-by-side produced the following results (source):

Technology Time
DB2 13min55s
PostgreSQL 8 14min50s
PostgreSQL 9 6min50s
Hadoop 3min37s
Cassandra 3min37s
Caché 2min25s

The first four will probably sound familiar even to schoolchildren. But what is Caché XEP?

10 9
1 882
Robert Cemper · Jul 4, 2020 2m read
Terminal Multi-Line Command Editor

The Command extension enables the execution of Multi-Line Commands from Terminal prompt.

Terminal Multi-Line Input with Edit, Insert, Delete, Print extension for IRIS and Caché
IRIS and Caché have just single command lines in terminal available
This Multi-Line Commands Editor also will execute the Multi-line Commands.
In addition, it is independent of access to %SYS and can be installed in any namespace

Special thanks to @Jeffrey Drumm who inspired me to this and supported me as beta-tester.

8 1
0 888
Daniel Tamajon · May 21, 2018
How is your code health

As a developer, usually I'm concerned about how my code health is, and how the other coders code can affect to my own work. And I'm quite sure most of us feel very similar.

In our company we use a Static Code Analysis tool to analyze code for different languages to ensure we are writing high quality and easily maintainable code by following a few best practices in terms of code structure and content. And the question was: why should be different for Caché ObjectScript language?

6 3
4 955

Creating your own commands or shortcut is one of the strongest features of ObjectScript
If you create your own Language Extensions to Object you mostly have to find the
proper %ZLANGC00 or %ZLANGV00 or %ZLANGF00 and add the extensions manually.

A few utilities do it already automatically (ZPM, ZME, ..)
This utility allows you to add your extensions programmatically. (eg. at first run, or during installation)
I found this quite useful for my Docker-based demos as it all happens at the start time.

It is related to these articles

5 0
0 238
Evgeny Shvarov · May 7, 2020 4m read
Unit Testing with ZPM

Hi Developers!

I want to share with you the approach you can use working with Unit Testing which I personally find very convenient and robust.

Will not talk much here about Unit Testing, we have documentation, enough good articles on the topic not only on the Internet but here on Developers Community too, e.g. this one.

How can you manage the Unit Testing of your ZPM module?

This is pretty handy with ZPM. It has a special command "test" which runs all the tests you mentioned in the module. You can execute it as shown below:

zpm:USER>module-name test

And this command runs all the tests you mentioned in module.xml.

Let's see how it works.

5 1
3 376
Evgeny Shvarov · Sep 21, 2020
Unit Testing Naming Convention

Hi Developers!

Recently we discussed the naming convention on packages we deploy and even made some choices.

Here I want to have a conversation on the naming convention for unit tests.

Of course, we wish every good library has unit tests. Here is the documentation and some good articles(one, two, three) regarding it on the Developer Community.

Let's decide on the naming of UnitTests packages?

The suggestion is that unit test classes will all start with the UnitTest package name.

E.g. if your library's class name is:


The related unit test class will be:


What about folders?

The suggestion is that unit test classes will live separately from source classes, e.g. in /tests directory.

Here is the example of a repository with unit tests that are named and placed according to the proposal.

What do you think?

5 6
0 226

InterSystems and Intel recently conducted a series of benchmarks combining InterSystems IRIS with 2nd Generation Intel® Xeon® Scalable Processors, also known as “Cascade Lake”, and Intel® Optane™ DC Persistent Memory (DCPMM). The goals of these benchmarks are to demonstrate the performance and scalability capabilities of InterSystems IRIS with Intel’s latest server technologies in various workload settings and server configurations. Along with various benchmark results, three different use-cases of Intel DCPMM with InterSystems IRIS are provided in this report.

5 5
0 706

A few years ago, I was teaching the basics of our %UnitTest framework during Caché Foundations class (now called Developing Using InterSystems Objects and SQL). A student asked if it was possible to collect performance statistics while running unit tests. A few weeks later, I added some additional code to the %UnitTest examples to answer this question. I’m finally sharing it on the Community.

5 2
2 486

Hi Developers!

This is yet another short post that is intended to simplify developers' life. Now we'll talk about how to make GitHub run unit tests with every push to the repository by adding just one file to the repo. For free. On Github Cloud. Sounds great, isn't it?

It is possible and very easy to do. Credit goes to @Dmitry Maslennikov (and his repo), ZPM Package Manager, and GitHub Actions. Let's see how this all works!

Something for Nothing by Robert Sheckley - YouTube

4 0
0 325
Oliver Wilms · Oct 5, 2020 2m read
File Passthrough Feeder

IRIS Interoperability Productions formerly known as Ensemble are fun to work with. Yes, I really think my work is fun. I have seen File Passthrough Services and File Passthrough Operations come in handy. At one point we placed test messages in files, then we utilized a File Passthrough Service with Inbound File Adapter to send the contents of the file as a Stream to a File Passthrough Operation with Outbound TCP Adapter.

4 1
0 268

Continuing on with providing some examples of various storage technologies and their performance profiles, this time we looked at the growing trend of leveraging internal commodity-based server storage, specifically the new HPE Cloudline 3150 Gen10 AMD processor-based single socket servers with two 3.2TB Samsung PM1725a NVMe drives.

4 2
0 1,111