Event Sourcing Course - Example Application

This repository contains an example event sourced application, used in Ambar's Event Sourcing course. You can take (or retake) the course for free in this link.

Getting Started

To run this application you need Docker. Once you have Docker installed, please clone the code, navigate to local-development and run dev_start.sh.

git clone [email protected]:ambarltd/courses-v2.git
cd courses-v2/local-development
./scripts/linux/dev_start.sh # if you're on linux
./scripts/linux/dev_start.sh # if you're on mac

Now open your browser to localhost:8080 and try the application out! You will receive further instructions in the top menu.

Contents

This example application contains an event sourced financial institution that allows you to:

1. Sign up
2. Verify your email
3. Sign in / sign out
4. View credit card products you can enrol in (Platinum and Starter)
5. Request an enrollment into a credit card product

The code for 1., 2., 3., and 4., is written in PHP, and lives at application/backend-php. The code for 5. is written in other languages to help you understand event sourcing in your preferred language. Currently, 5. is available in Java, C#, and Typescript.

By default 5 is deployed with Java. But if you'd like to change that, simply head to local-development/docker-compose.yml and change the backend-credit-card-enrollment service to use the directory corresponding to your preferred language.

Building More

If you change the code, simply redeploy your Docker containers, and refresh your browser.

cd courses-v2/local-development
# For Linux
./scripts/linux/dev_start.sh 
./scripts/linux/dev_start_with_data_deletion.sh # use this if you want to delete your existing event store, and projection db
# For Mac
./scripts/linux/dev_start.sh 
./scripts/linux/dev_start_with_data_deletion.sh # use this if you want to delete your existing event store, and projection db
# Windows support (todo) - feel free to add a Pull Request ;)

Making Sense of the Code

To make sense of this application, please review the slides and recordings you received during your course.

application/                         # Source code
├── frontend-javascript/             # Source code for the frontend
└── backend-php/                     # Source code for the backend (parts 1-4)
└── backend-credit-card-enrollment/  # Source code for the backend (part 5)

cloud-deployment-examples/  # Infrastructure code examples, in case you ever want to deploy this to the cloud.

local-development/          # Local development environment defined with Docker Compose
│
│
├── docker-compose.yml      # Docker Compose definition
│                           #     Includes an event store (Postgres), projection db (Mongo),
│                           #     backends, frontend (JavaScript + Nginx), and an Ambar 
│                           #     emulator (for projections and reactions)
│
│
├── ambar-config.yml        # Configuration for Ambar emulator
│                           #     Needed for projections and reactions as per 
│                           #     https://hub.docker.com/r/ambarltd/emulator
│
├── scripts.                # Scripts to start/stop the application's containers.

Support

If you get stuck, please ask us questions in the #event-sourcing channel of our Slack community. If you're not part of our Slack, please sign up here. Or if you'd like a free private walkthrough, simply book one here.