Email Microservice - [EMAIL]
Email Microservice of an Email Messenger System based on @MichelliBrito's classes
| Overview | Technologies | Project | Routes | Run | Author |
This application is an implementation of a Microservices Architecture using RabbitMQ for queue communication and the best practices of Clean Architecture, SOLID and DDD, all documented. Use Docker to handle the entire system structure.
| User Microservice: [ https://github.com/Samuel-Ricardo/ems_user ]
- Spring Framework
- RabbitMQ
- PostgreSQL
- Docker
- Microservice
- Communication Between Microservices
- Email SMTP
- Maven
- REST
- Swagger
- Validation
- Lombok
- Environment
- Clean Architeture
- DDD
- JUnit
- H2 Database
- Error Handler
Among Others...
Giving an overview, this architecture is divided into User Microservice and Email Microservice, each with its own databases, communication between them occurs through a broker which in this case is based on asynchronous queues managed by RabbitMQ
| Repository: [ https://github.com/Samuel-Ricardo/ems_user ]
The main function of User Microservice is to list and register users in a database. When a user is saved in this MS, it publishes this event to the broker.
| Repository: [ https://github.com/Samuel-Ricardo/ems_email ]
The main function of the Email Microservice is to send a welcome email to new users, for this it listens to the broker, when a created user event is published this MS consumes this event and sends an email to this new created user welcoming .
The broker is an intermediary between microservices, it receives events and store in a Queue Data Structure that is triggered and can be consumed by other microservices that are waiting for it to react.
$ git clone "git@github.com:Samuel-Ricardo/ems_email.git"
$ git pull "git@github.com:Samuel-Ricardo/ems_email.git"
This application use Docker so you dont need to install and cofigurate anything other than docker on your machine.
Navigate to project folder and run it using docker-compose
# After setup docker environment just run this commmand on root project folder:
$ docker-compose up --build # For First Time run this command
$ docker-compose up # to run project
#Apps Running on:
$ USER: http://localhost:8080 - [MICROSERVICE] | [USER]
$ EMAIL: http://localhost:8081 - [MICROSERVICE] | [EMAIL]
$ SWAGGER: http://localhost:8080/swagger-ui/index.html - [DOCS]
$ PostgreSQL: http://localhost:5431 - [DATABASE] | [USER]
$ PostgreSQL: http://localhost:5432 - [DATABASE] | [EMAIL]
$ PGAdmin: http://localhost:5050 - [DATABASE] | [VIEW]
$ RabbitMQ: :5672 - [BROKER]
$ RabbitMQ: http://localhost:15672 - [BROKER] | [VIEW]
See more: docker-compose.yaml
- Samuel Ricardo
Extended technical documentation — generated from a full codebase analysis. The sections above remain the canonical project README; this section complements it with engineering deep-dives.
flowchart LR
U[👤 ems_user<br/>8080] -- "user.created event<br/>(JSON → EmailDTO)" --> Q[(🐰 RabbitMQ<br/>queue: default.email)]
Q --> L[📬 RabbitMQEmailConsumer]
L --> S[⚙️ EmailService]
S --> M[✉️ SMTP<br/>Gmail :587]
S --> DB[(🐘 PostgreSQL<br/>TB_EMAILS :5432)]
Java 17 · Spring Boot 3.2.0 (Web, Data JPA, AMQP, Mail, Validation) · RabbitMQ · PostgreSQL / H2 · Lombok · springdoc-openapi · Maven · Docker · GitHub Actions + cosign
| # | Doc | Content |
|---|---|---|
| 00 | Docs Index | navigation hub |
| 01 | Overview | context, features, system scope |
| 02 | Architecture | C4 views, layers, patterns |
| 03 | Messaging | RabbitMQ contract, EmailDTO payload |
| 04 | Data Model | entity, status machine, schema |
| 05 | Configuration | env vars, profiles, secrets |
| 06 | Testing | strategy, gaps, coverage gate |
| 07 | Deployment | Docker, compose, CI/CD, K8s |
| 08 | Security | findings & hardening |
| 09 | Development | build, run, conventions |
| 10 | Improvement Backlog | prioritized enhancements |
| — | ADRs | architecture decision records |
Rotate the SMTP credentials historically present in .env — see docs/08-security.md.