Skip to main content

Intro

This web-site explores the idea that data has a dual nature - a stream (flow) and a particle (id) - an idea inspired from physics that light has the dual nature - wave and particle. It is collection of design notes on multiple, seemingly unrelated, topics that follow from this core assumption.

Calin Groza

Popular posts from this blog

Performance Testing a New CRM

Performance testing  is challenging, frustrating, often underestimated typically getting attention only after an incident. How did we the performance test and what did we learn during the development and implementation of  web-services for a new CRM system?
Read more

View - A Functor for Web App Design

This blog is about practical applications of Category Theory to the development of Java + Spring applications. I am looking at a design approach to simplify the development of web applications. Traditionally, this kind of back-office application is based on the Web 1.0 technology stack, using Spring Boot and Thymeleaf. My approach is to keep using Spring Boot but replace the generation of HTML with J2HTML and higher-order views. From a Category Theory point of view, we can look at web applications as mappings from the Category of Business Entities and the Category of UI Widgets. If we go one step further, both business entities and UI widgets are mapped to Java classes. Thus, we can view a web application (or a part of it) as an endofunctor in the Category of Java Classes. We define the View-functor as follows: domain(V) - Java classes representing business entities - e.g., Invoice, User - and, codomain(V) - Java functions that render the business entity as a DomContent object (DomCont...
Read more

Spring Boot to AWS Elastic Beanstalk

Beanstalk is an AWS-managed service that allows applications to run containerized in AWS. I am using Elastic Beanstalk (EB) to deploy quickly developed applications when the emphasis is on time-to-market rather than all the features of an enterprise application. For the purpose of this post, I will use the application called Genova  as an example. It is a web application that exposes HTML and JSON content. Step 1 - Create a Spring Profile for AWS Beanstalk The configuration of Spring Boot application is applications-<profile>.yml files that are in the src/main/resources folder. By default, an EB deployment listens to the port 5000. For this reason I am creating the file application-eb.yaml with the following content: server:  port: 5000 Step2 - Build the Spring Boot Application Using maven to create the Spring Boot jar file: mvn clean package -DskipTests This command creates a file with the name genova-1.0.0-SNAPSHOT.jar    in the target  folder. Step 3 -...
Read more