Article
· Mar 28, 2019 2m read
ObjectScript error handling snippets

ObjectScript has at least three ways of handling errors (status codes, exceptions, SQLCODE, etc.). Most of the system code uses statuses but exceptions are easier to handle for a number of reasons. Working with legacy code you spend some time translating between the different techniques. I use these snippets a lot for reference. Hopefully they're useful to others as well.

24 5
23 3.8K
Article
· Jul 8, 2020 7m read
Tips for debugging with %Status

Introduction

If you're solving complex problems in ObjectScript, you probably have a lot of code that works with %Status values. If you have interacted with persistent classes from an object perspective (%Save, %OpenId, etc.), you have almost certainly seen them. A %Status provides a wrapper around a localizable error message in InterSystems' platforms. An OK status ($$$OK) is just equal to 1, whereas a bad status ($$$ERROR(errorcode,arguments...)) is represented as a 0 followed by a space followed by a $ListBuild list with structured information about the error. $System.Status (see class reference) provides several handy APIs for working with %Status values; the class reference is helpful and I won't bother duplicating it here. There have been a few other useful articles/questions on the topic as well (see links at the end). My focus in this article will be on a few debugging tricks techniques rather than coding best practices (again, if you're looking for those, see links at the end).

15 8
11 2.3K

The Good Old Days

The %Library.DynamicObject class has been in IRIS since before it became IRIS. If you have been using it since the Cache days, you may want to brush up on some of its changes.

In Cache 2018, the %Get method only had one argument. It was the key to retrieving from the JSON, meaning that if your JSON object called myObj, it would look like the following:

8 3
3 194

If you have system tables implementing the "VERSIONPROPERTY" functionality, you may encounter error 5800. This article explains how this error occurs and provides solutions to resolve the issue.

When version checking is implemented, the property specified by VERSIONPROPERTY is automatically incremented each time an instance of the class is updated (either by objects or SQL).

For example:

8 0
0 239

Hi Community,

In this article, we will explore the concepts of Dynamic SQL and Embedded SQL within the context of InterSystems IRIS, provide practical examples, and examine their differences to help you understand how to leverage them in your applications.

InterSystems SQL provides a full set of standard relational features, including the ability to define table schema, execute queries, and define and execute stored procedures. You can execute InterSystems SQL interactively from the Management Portal or programmatically using a SQL shell interface. Embedded SQL enables you to embed SQL statements in your ObjectScript code, while Dynamic SQL enables you to execute dynamic SQL statements from ObjectScript at runtime. While static SQL queries offer predictable performance, dynamic and embedded SQL offer flexibility and integration, respectively.

6 5
0 172
Article
· Feb 7 4m read
IRIS %Status and Exceptions

You may encounter errors during any point of program execution, and there are several ways to raise and handle these exceptions. In this article, we'll explore how exceptions are handled efficiently in IRIS.

One of the most commonly used return types is %Status, which is used by methods to indicate success or failure. Let's begin by discussing %Status values.

Working with %Status

4 0
1 189

In this article, exceptions are covered.

Working with Exceptions

Instead of returning a %Status response, you can raise and throw an Exception. You are then responsible for catching the exception and validating it. IRIS provides five main classes to handle exceptions effectively. Additionally, you can create custom exception class definition based on your needs.

3 0
0 188
Article
· Apr 25, 2024 3m read
Making A Variable Watch Itself

I came up with a challenge for myself to come up with a way to make a variable watch itself for a certain value and do something when it hits that value without having to check it every time something touches it. Basically, a way to say "if at any point during the execution of this code, if x = 0 (or whatever the condition is) do this thing." The class I ended up with watches a %Status:

3 0
0 287
Article
· Aug 2, 2020 1m read
Application Errors Analytics

Hi Developers!

As you know the application errors live in ^ERRORS global. They appear there if you call:

d e.Log() 

in a Catch section of Try-Catch.

With @Robert.Cemper1003's approach, you can now use SQL to examine it.

Inspired by Robert's module I introduced a simple IRIS Analytics module which shows these errors in a dashboard:

3 5
1 363
Article
· Oct 6, 2016 4m read
RESTful Exception Handling

A beginner’s guide to Exception Handling in RESTful web services. The article gives an example how the various error conditions during processing a service request can be handled.

We expect our client – server communication working in a flawless operational condition, running error free software. But we are prepared to handle exceptions. Are we? So far in the examples of the previous sessions were not. We did not care about exceptions. The result? In any error incident it took ages to figure out what the problem is and more importantly how to fix it.

3 1
0 1.8K

Work Queue Manager (WQM) is a feature of InterSystems IRIS that enables you to improve performance by distributing work to multiple concurrent processes programmatically. The idea is that you split the work into chunks, and WQM distributes the chunks across worker processes and can provide the info that the work is done.

However, recently, I got an interesting question: there's a large logical transaction composed of ~1,000,000 individual objects and SQL inserts and updates. Some updates are CPU-intensive, so the original idea was to use WQM to split an update into chunks to speed things up.

But, here's a catch: if one of the individual 1,000,000 changes fails (there's a variety of application-level checks so that it can fail, and that's not even that abnormal a behavior), the entire transaction must be rolled back. That creates a problem: each chunk must report success before committing their individual transactions, and someone must get all these reports and decide if we are committing or not.

Unfortunately, it looks like WQM does not have a bidirectional communication between workers and manager, so I suggested an approach using events:

  1. Start jobs.
  2. Wait for all jobs to report success using $System.Event.WaitMsg().
  3. Send Commit or Rollback using the $System.Event.Signal().
2 9
2 288

Hi InterSystems Community

We recently had an issue where we weren't able to parse a JSON HTTP request, but the issue went by unnoticed. We also did not have a trace of what the raw HTTP request was that we couldn't parse. I'm looking at improving our this by:
Tracing the raw request using $$$TRACE

Raising an alert which will hit our Ens.Alert router which will compose and send an email

1 0
1 322

Hi all,

I have a rule to throw a message when there is an error. I want to prevent send the email if the origin of the error is the API to send the email

This is my rule

Now, If there is any error in any process, it works, but if there is an error in MyProduct.BO.SendEmail it is trying to send the error again, and it is a infinite loop.

Is there any way to check what is the origin and don't process if the origin is MyProduct.BO.SendEmail?

1 2
0 350
Discussion
· Sep 28, 2020
%Status usage in ObjectScript

Hi developers!

Want to discuss with you the case of %Status.

If you familiar with ObjectScript you know what is it. I'd love to hear the history of the case why it had appeared in ObjectScript but it turned out that almost every system/library classmethods return %Status and there is a whole set of tools to deal with it.

What is does it gives you the responsibility to check the value or %Status of every system method you call.

E.g. if you save the data of the persistent class, you should never call like this:

do obj.%Save()

you need to call:

set sc=obj.%Save()

if $$$ISERR(sc) do // something or quit.

1 19
0 1.2K

We have a data transformation where source is object collection (populated from a json file) and target is EnsLib.EDI.XML.Document.

If source file is large enough, transformation fails and we get <store> error and I quickly found this:

https://docs.intersystems.com/irislatest/csp/docbook/DocBook.UI.Page.cls?KEY=EBPLR_DTL_foreach which at the bottom in "Avoiding <STORE> Errors with Large Messages" section tells to:

1 1
0 485