IAM Backend Exercise

Welcome to the IAM (Identity and Access Management) Backend Exercise! This repository contains a simple structure to help you implement and work with an event-driven backend system. The exercise focuses on handling events that manipulate and maintain data related to Organizations and Users within an IAM system.

This exercise is using an event-driven approach following a producer-consumer pattern. We are providing the producer, you will be implementing the consumer, located in src/consumer/index.ts. The goal is to process received events and react according to the business logic.

Purpose

The goal of this exercise is to implement an event handler capable of consuming and processing events to materialize the state of the data into a database. The system simulates real-world scenarios where:

• Users belong to multiple Organizations.
• Users can have different roles within each Organization.
• Events dynamically update the state of the system.

The producer may send erroneous or out-of-order payload, just like it could happen in a real world environment.

Entities

The system revolves around two main entities:

User

Represents an individual within the IAM system.

• id (string): Unique identifier for the User.
• name (string): Full name of the User.
• email (string): Email address of the User.

Organization

Represents a group or entity within the IAM system.

• id (string): Unique identifier for the Organization.
• name (string): Name of the Organization.

OrganizationUser

Represents the relationship between a User and an Organization.

• organizationId (string): ID of the Organization.
• userId (string): ID of the User.
• role (string): Role of the User within the Organization. Possible values are:
  • admin
  • writer
  • reader

Events

The system uses an event-driven architecture. The following event types are consumed:

1. UserCreated

   • Triggered when a new User is created.
   • Payload includes the User's details.

2. OrganizationCreated

   • Triggered when a new Organization is created.
   • Payload includes the Organization's details.

3. OrganizationUserAdded

   • Triggered when a User is added to an Organization with a specific role.
   • Payload includes the organizationId, userId, and role.

4. OrganizationUserRemoved

   • Triggered when a User is removed from an Organization.
   • Payload includes the organizationId and userId.

5. OrganizationUserUpdated

   • Triggered when a User's role within an Organization is updated.
   • Payload includes the organizationId, userId, and updated role.

Exercise

Your task is to implement an event handler that:

1. Consumes the events in random order.
2. Materializes the data into a database to reflect the current state of the system.
3. Ensures relationships between Users, Organizations, and their roles are consistent.

Guidelines

1. Use the provided entities and events structure to create your solution.
2. Implement validation and error handling for event processing.
3. Store the state in a way that allows querying Users by Organization and vice versa.

Additional Notes

• You may use any database or in-memory store for state materialization.
• Focus on writing clean, maintainable code.
• Consider edge cases, such as duplicate events or events with missing data.

Getting Started

1. Clone the repository:

   git clone https://github.com/ageras-com/iam-backend-exercise.git

2. Install dependencies:

   npm install

3. Start implementing your solution in the appropriate files.

4. Run tests (if any):

   npm test

Example Workflow

1. A UserCreated event is received with the payload:

   {
     "id": "user-1",
     "name": "Alice",
     "email": "[email protected]"
   }

   The event handler creates a new User entry in the database.

2. An OrganizationCreated event is received with the payload:

   {
     "id": "org-1",
     "name": "TechCorp"
   }

   The event handler creates a new Organization entry in the database.

3. An OrganizationUserAdded event is received with the payload:

   {
     "organizationId": "org-1",
     "userId": "user-1",
     "role": "admin"
   }

   The event handler associates the User with the Organization and assigns the admin role.

Conclusion

This exercise is designed to test your ability to work with event-driven systems, data modeling, and backend architecture. Good luck, and feel free to be creative with your implementation!