Kevin's Blog

Test Command Handler With Mock

This post demonstrates how to test command and query handlers in a Command Query Separation based project.

Command Query in Go Project

In Model-View-Controller applications, a common practice is to introduce service objects to encapsulate business logic and manage the interaction to external systems. While service objects are useful abstraction, further structuring them could improve the code organization and maintainability. Command Query Separation (CQS) is a design pattern principle that defines the incoming request handler type, which is either modify the application state - commands, or retrieving data without any side effect - queries. By applying CQS to service objects, we can create clean interface. This blog post will explore further the benefits of CQS and how to create command and query objects in existing application.

Application Validation and Error Handling

Some practices and patterns for handling exceptions in Java application.

User Authentication With Springboot using local database

This post explains how to configure the spring security for your app to support user authentication using local database.

Tracking Email Activity Ses

This post explains in detailed how to track email sending activities using SNS HTTPs endpoint.

Setup local domain with self-signed SSL certificate

This is a post about setting up the local domain and SSL certs for testing purpose.

A project specific command-line

Build a commandline tool that helps bootstrap the project

A Simple Infrastructure

Idea of building the infrastructure with Amazon Web Service using Terraform, Ansible and Jenkins.