Building a Scalable Microservices Application with Java Spring Boot and Angular

PART 1 - The First Consultation

Look, while I enjoy microservices as much as the next guy, do I think that they are a huge headache to deal with and debug? Yes. But, the microservice architecture is such a hot button topic amongst devs and recruiters that I'd be amiss to not sandbox my own massive scalable project that's production ready while also keeping costs low or non existent cause hey, we're all broke. 

The Scenario:

Congratulations! You were hired at IceToMeetYou Inc. as a consultant and they are looking to upgrade their current shipping management software to a more custom solution. IceToMeetYou Inc. is a startup who just got about $3B dollars in funding for their product that sells imported ice cubes to one guy stuck in the desert. Their current task management software is too small and limited in its functionality to handle all the incoming shipments this one guy, lets call him Dennis, needs to keep his smoothie cold. They want to build some task management system that can handle multiple incoming orders from Dennis to completion, assign orders to their worker penguins delivering the ice, track the progress of said penguins and receive real time notifications of status updates. With this, the CEO says to please feel free to ask any questions that can help build this project. We are going to be doing just that as we start to think about the project build…

Tech Stack:

For this project, we will use the following tech stack:

Backend: Java Spring Boot due to it being a powerful framework for building REST APIs and microservices, offering a wide array of tools like service discovery, cloud deployments, and Kafka for event-driven systems.
Frontend: Angular due to its robust front-end framework with NgRx for global state management
Database: MySQL/PostgreSQL (for relational data), MongoDB (for task data)
Real-time updates: Kafka (for event streaming) and WebSockets
Deployment: Docker and Kubernetes for orchestration
Testing: JUnit, Jest, and K6 (for load and performance testing)

The Big Picture:

The main purpose here is to demonstrate all the movable parts when thinking about a web application. While in no part is this list exhaustive, the goal is to cover a lot of bases in plain English so that this process is repeatable and a no brainer when thinking about enterprise applications. For each section, I will showcase each step from design to deployment to pass for a V1 MVP via deep dive blogs, code demonstrations, diagrams, thought processes and most importantly, always making sure we are solving the problem.

Microservice Architecture:

 → Design Principles: Understanding and implementing microservices principles such as service independence, scalability, and fault tolerance
 → Service Isolation: How to separate into its own areas of concern,
 → Inter-Service Communication: Choosing communication strategies (REST APIs, Kafka, WebSockets) and handling data consistency across services.

Backend Development With Spring Boot:

 → Service Development: Implementing individual services using Spring Boot, handling RESTful endpoints, and ensuring proper isolation of concerns.
 → Authentication & Security: Using JWTs, OAuth, and Spring Security for secure user authentication and role-based access control.
 → Database Management: Setting up relational (MySQL/PostgreSQL) and NoSQL (MongoDB) databases, optimizing data storage for microservices, and handling data migrations.

Frontend Development With Angular:

→ User Interface Design: Creating a seamless user experience using Angular
 → State Management: Handling application state with NgRx for consistent, reactive user interactions.
 → API Integration: Connecting the Angular front end to Spring Boot backend services via RESTful APIs and managing data transfer securely.

Real Time Data Communication and Notifications:

→ Websockets & Event Streaming: Implementing WebSockets for instant updates and Kafka for reliable event streaming between services.
 → Push Notifications: Delivering real-time updates to users, ensuring efficient message distribution without overloading services.

Performance Testing & Monitoring:

→ Load Testing: Using K6 to assess the system under load, identifying bottlenecks, and optimizing microservices for performance.
 → Logging & Monitoring: Implementing logging with ELK or alternative tools, tracking application health, and setting up alerts for critical failures.

Deployment & Scaling:

→ Containerization With Docker: Building Docker images for each service, establishing a consistent runtime environment for easier scaling.
 → Orchestration With Kubernetes: Using Kubernetes to manage deployments, auto-scaling, load balancing, and resilience.
 → Cloud Hosting: Hosting services on cloud platforms (AWS, Azure, GCP), covering aspects like cost efficiency, security, and reliability.

Some Final Thoughts Before Show Time...

For starters, its a sandbox so this project is built for learning and demonstration. Big note here: This is a 100% over engineered solution built from scratch by one guy sitting in a basement. It's not that serious. 

I will be updating and working on this project everyday so expect frequent updates! 

This is also an exercise in what development would be like within a team setting, so we will be working within "sprints" to hit our goals with retrospectives (with, I guess, myself?) to see what went right, what went wrong, what blockers did we come across and how can we solve them. I will update doing a quick retro every 5 posts or so.

ONE MORE THING…I am always ALWAYS hungry for feedback. If something doesn't make sense or is not clear enough, let me know in the comments. 

So, its getting late, Sprint 1 starts tomorrow, hold on to your hats, its going be a long day…