TL;DR: Collect debug information in an in-memory buffer that is printed to the output when an error occurs (and quietly discarded in all other cases). I may have come up with a useful idea. Or something that is not all that useful. Or even something that already exists (and I […]
javascript
Azure Pipelines: publish to Azure Artifacts
This article is a follow-up to my previous article about using Azure Artifacts for own NPM modules. In that article I showed how to create a NPM module by hand on your local system and publish it to Azure Artifacts. But now we like to integrate it into CI/CD, so […]
Using Azure Artifacts for your own NPM modules
Currently I am working on a customer project in which we build a lot of Azure (serverless) functions, mostly in Javascript. Sometime ago we foresaw that we need some shared functionality which was to be used in multiple functions. So wouldn’t it be a good idea to create some shared […]
DIY Kafka Topic Watcher tool – Node, Express, Server Sent Events and Apache Kafka
This article can be read in at least two different ways: as a somewhat lengthy introduction of a handy tool that you can easily run to inspect messages published to the topics in a Kafka Cluster as a detailed yet basic example of how to combine several techniques to create […]
A Free Apache Kafka Cloud Service – and how to quickly get started with it
Last week I presented on Apache Kafka – twice. Once to a group of over 100 students, once to 30+ colleagues. In both instances, I invited attendees to partake in a workshop with hands-on labs to get acquainted with Apache Kafka. I had prepared a Docker Compose based Kafka platform […]
JavaScript: Mapping and Wrapping Classic Callback Functions to Promises and Async / Await
Callback functions used to be very common in JavaScript and Node applications. Out of necessity. And with Callback functions came unclear program flows, parallel realities, nested complexity and more. ECMAScript introduced Promises several years ago and followed that up with the neat await and async syntax. This allows us to […]
Override Date.now() based on OS time when Node returns incorrect current date
I was facing a weird issue. In my Node application – version 10.6.3 – running on Ubuntu – 18.04 – I got the wrong value for the current date and time. A call to new Date() and to Date.now() resulted in a wrong value, off by over two months: The […]
Node JS application running on GraalVM – interoperating with Java, Python, R and more
When you install GraalVM, one of the things you get is a Node runtime environment (GraalVM 19.2.1 is based on Node 10.16.3 – with support for the core Node libraries and un understanding of NPM modules – and has a JavaScript engine that is ECAMScript 2019 compliant). Instead of V8, […]
Python application running on GraalVM and Polyglotting with JavaScript, R, Ruby and Java
GraalVM is among other things a polyglot language runtime. It can run applications written in many languages – JVM languages like Java, Scala, Groovy and Kotlin as well as non-JVM language such as Python, R, Ruby, JavaScript and LLVM. GraalVM also allows applications in any of these languages to execute […]
Create a Native Image Binary Executable for a Polyglot Java Application using GraalVM – using build time class initializing
GraalVM provides a runtime component that enhances the JVM in several ways. It makes the JIT compilation better. It also allows the JVM to run non-JVM languages such as JavaScript, R, Python, Ruby and LLVM. And it makes it possible for languages running on the JVM to interact – through […]
Leverage NPM JavaScript Module from Java application using GraalVM
Interoperability from Java to JavaScript has been an objective for the Java community for quite a while. With GraalVM, there is great way to run JavaScript code from within Java applications. The interaction itself is faster, more robust and more ‘native’ (rather than bolt-on) than earlier mechanisms. For developers, the […]
Calling out from Java to JavaScript (with call back) – leveraging interoperability support of GraalVM
Interoperability from Java to JavaScript has been an objective for the Java community for quite a while. With Rhino and later Nashorn, two valiant attempts were made to add scripting interaction to the JDK and JVM. Now, with GraalVM, there is a better alternative for running JavaScript code from within […]
Graceful shutdown of forked workers in Python and JavaScript running in Docker containers
You might encounter a situation where you want to fork a script during execution. For example if the amount of forks is dependent on user input or another specific situation. I encountered such a situation in which I wanted to put load on a service using multiple concurrent processes. In […]
The Pipelined Pancake Party – demonstrating the Power of Parallelization and Pipelining in JavaScript with Promises and Asynchronous Generators
This article is an attempt to demonstrate the performance gains – and programming elegance – that is at our disposal with the advent of asynchronous generators in ES 2018 (JavaScript), for example in Node 10 and later. With asynchronous generators and Promises, we can implement parallel, asynchronous and pipelined processing […]
JavaScript Pipelining using Asynchronous Generators to implement Running Aggregates
As of ES 2018 (recent browsers or Node 10), JavaScript support asynchronous generators. Generators are functions that return a set of values, one value at a time. These values can be processed inside the code that invokes the generator immediately, as soon as they become available. There is no need […]
JavaScript Generators – How functions return a stream of results, yielding one result at a time
It was through inspecting some Python code that relied quite heavily that I suddenly realized the beauty of the ES6 concept of generators and the yield keyword. A generator function does not return its result all at once but instead an iterator that can be read from, one value at […]
Building a Conference Session Agenda with Oracle APEX – notes on Pivot, Modal Popup and jQuery
AMIS is part of the Conclusion ecosystem of over 20 companies, each with their own specialty and identity. Several times per year, we organize Conclusion on Stage – a conference that spans across the ecosystem. Presenters from most companies under the Conclusion umbrella submit session proposals. Close to 30 sessions […]
How to use any Oracle JET Component in VBCS
Oracle JET has more components than available in VBCS. Using Web Components you can extend VBCS yourself with the missing JET components. In Oracle JET you can add a Paging control to a table. For that you have to use a PagingDataSource. The Paging Control and PagingDataSource are (out of […]
Some neat APEX tricks while building a Session Like application for our Conference
AMIS is part of the Conclusion ecosystem of over 20 companies, each with their own specialty and identity. Several times per year, we organize Conclusion on Stage – a conference that spans across the ecosystem. Presenters from most companies under the Conclusion umbrella submit session proposals. Close to 30 sessions […]
Quickly setup a persistent React application
After having recently picked up the React framework, I figured I’d share how I quickly setup my projects to implement persistence. This way you spend minimal time setting up the skeleton of your application, letting you focus on adding functionality. This is done by combining a few tools. Let’s take […]