Automated Unit Testing of Javascript Fn Functions using Jest

Lucas Jellema

Crucial pieces of functionality in cloud native applications is implemented in Functions. In the case of Oracle Cloud Infrastructure specifically, the Functions framework is typically Project Fn and the implementation language of choice is … up to the DevOps team. Popular languages for implementing Functions include Go, Python, Java and […]

The Pipelined Pancake Party – demonstrating the Power of Parallelization and Pipelining in JavaScript with Promises and Asynchronous Generators

Lucas Jellema

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 […]

Some of my Solutions for challenges with Oracle JET

Lucas Jellema 5

This article is not some sophisticated treatise on Oracle JET fundamentals.It is merely a collection of challenges I had to deal with and found solutions for – that work, even if they are perhaps not the best approach around. This article is first of all a personal notebook. If you […]

Implementing Authentication for REST API calls from JET Applications embedded in ADF or WebCenter Portal using JSON Web Token (JWT)

Lucas Jellema 1

The situation discussed in this article is as follows: a rich client web application (JavaScript based, could be created with Oracle JET or based on Angular/Vue/React/Ember/…) is embedded in an ADF or WebCenter Portal application. Users are authenticated in that application through a regular login procedure that leverages the OPSS […]

When Screen Scraping became API calling – Gathering Oracle OpenWorld 2017 Session Catalog with Node

Lucas Jellema

A dataset with all sessions of the upcoming Oracle OpenWorld 2017 conference is nice to have – for experiments and demonstrations with many technologies. The session catalog is exposed at a website –  With searching, filtering and scrolling, all available sessions can be inspected. If data is available in […]

Node.js run from GitHub in Generic Docker Container backed by Dockerized Redis Cache

Lucas Jellema

In a previous article I talked about a generic Docker Container Image that can be used to run any Node.js application directly from GitHub or some other Git instance by feeding the Git repo url as Docker run parameter (see In this article, I create a simple Node.js application […]