#Caché

Cache tricks

Several years ago, long before Developer Community Portal was launched, I published a series of Caché tricks at one of Czech web sites. In this article, I’m posting translated version of one of them.

Capturing output of someone else’s methods or routines

Suppose you, or someone else created a useful method or routine, that was producing some computation that you’d like to benefit from, but the routine was writing output to process principal device.

You would like to use the data, but you need it not written to a device, but assigned to a variable. And, for any reason, you can’t modify the code. What can you do?

We are building a bunch of rest based services using Ens 2016.2 to serve our browser based application (Angular 4).

Two questions:

1. The initial authentication seems only work if credentials are placed in the url parameters. Trying to use the Authorization header instead, the client code immediately complains about Access-Control-Allow-Origin. How can I resolve this?

2. After initial authentication, what is the proper way to send subsequent rest calls without having to include credential every time?

Some may think it's a strange / daft idea, but just today the Raspberry Pi folks have announced that they've now sold more than 10 million of them..and counting. That's a huge potential marketplace, and a great platform for getting people to hear about Cache and try it out. Given its focus on the education sector, another great way of getting heard about.

By now it's a commonplace how to implement a basic REST API in Caché and there is good documentation about it here: REST in Caché

A question that comes up from time to time is:

How can I make a parameter in my REST url optional?

Simply put, is it possible to create a URL map in Caché that maps a URL like this:

Apache Spark has rapidly become one of the most exciting technologies for big data analytics and machine learning. Spark is a general data processing engine created for use in clustered computing environments. Its heart is the Resilient Distributed Dataset (RDD) which represents a distributed, fault tolerant, collection of data that can be operated on in parallel across the nodes of a cluster. Spark is implemented using a combination of Java and Scala and so comes as a library that can run on any JVM.

There have been a few use cases recently within InterSystems where we've needed to connect to Caché-based web services from PHP. The first of these was actually the Developer Community itself, which uses web services as part of Single Sign-On with other InterSystems sites/applications. The following example demonstrates how to connect to a Caché-based web service (particularly, the web service in the SAMPLES namespace) from PHP, using password authentication.

Quality of Service Mirroring Timeout Configuration

GraphQL is a standard for declaring data structures and methods of data access that serves as a middleware layer between the client and the server. If you’ve never heard about GraphQL, here is a couple of useful online resources: here, here and here.

In this article, I will tell you how you can use GraphQL in your projects based on InterSystems technologies.

404 Not Found

{
"error": {
 "errors": [
  {
   "domain": "global",
   "reason": "notFound",
   "message": "Not Found"
  }
 ],
 "code": 404,
 "message": "Not Found"
 }
}

I want to do something like the above sample from a Google Storage JSON API. I have a call to Write obj.%ToJSON() followed by return ..ReportHttpStatusCode(..#HTTP404NOTFOUND) however the HTTP Status code is always 200. If I remove the Write obj.%ToJSON() statement it returns a 404 status with no body. How do I return both?

Date range queries going too slow for you? SQL Performance got you down? I have ANOTHER weird trick that SQL Developers don't want you to know!*

In this series of articles, I'd like to present and discuss several possible approaches toward software development with InterSystems technologies and GitLab. I will cover such topics as:

• Git 101
• Git flow (development process)
• GitLab installation
• GitLab Workflow
• Continuous Delivery
• GitLab installation and configuration
• GitLab CI/CD
• Why containers?
• Containers infrastructure
• CD using containers

In the first article, we covered Git basics, why a high-level understanding of Git concepts is important for modern software development, and how Git can be used to develop software.

In the second article, we covered GitLab Workflow - a complete software life cycle process and Continuous Delivery.

In the third article, we covered GitLab installation and configuration and connecting your environments to GitLab

In the fourth article, we wrote a CD configuration.

In the fifth article, we talked about containers and how (and why) they can be used.

In the sixth article let's discuss main components you'll need to run a continuous delivery pipeline with containers and how they all work together.

In this article, we'll build Continuous Delivery configuration discussed in the previous articles.

If your application is raising <PROTECT> errors and you're finding it hard to work out why, here's a way to get additional information.

First, if auditing is not already enabled, turn it on:

Then use "Configure System Events" (highlighted above) and locate the event named %System/%Security/Protect. In the screenshot below I used the Filter field to do this (type "protect" - highlighted below - and press TAB):

InterSystems is happy to announce the availability of our newest Data Platforms release: Caché and Ensemble 2016.2

The highlights of 2016.2 are:

Listout the Difference between Cache object script and Mumps