platform-challenge

Background

Gr4vy is a building a payment orchestration platform.

As a Platform engineer, you are tasked with improving the engineering efficiency by producing automation tools that provision services in an efficient, predictable and reproducible way.

In this exercise we use HTTPie in our examples for clarity.

Architecture Overview

+----------------------------------+
|            Merchant              |
+-+--------^------------+--------^-+
  |        |            |        |
 (1)      (2)          (3)      (5)
  |        |            |        |
+-v--------+-+        +-v--------+-+        +-----------------+
|  Auth API  |        |  Core API  |        |  PSP Connector  | 
+------------+        +------+-----+        +---------^-------+
                             |                        |
                            (4)                      (6)
                             |                        |
                      +------v------------------------+-------+
                      |          Redis Message Queue          |
                      +---------------------------------------+

There are 3 distinct services:

• Auth API - Creates authentication tokens to valid users.
• Core API - Processes transaction requests.
• PSP Connector - Processes the transactions with a Payment Service Provider (PSP).

A transaction flow is as follows:

1. A merchant authenticates with the Auth API by providing a valid username and password.
2. An authentication token that is valid for 30 seconds is returned.
3. Use this authentication token to make a transaction request to the Core API.
4. The Core API submits the transaction to a message queue for further background processing.
5. A successful response is returned.
6. Meanwhile, a PSP Connector processes the transaction from the message queue by connecting to a Payment Service Provider.

We use environment variables to configure a service.

Your task

• Read the documentation for each service. Run and test them to make sure they work as expected.
• Once you're familiar with the services, use your preferred tools to automate provisioning of a local development environment.
• Be sure to include external dependencies like Redis and configuration management.
• In order for a microservices-based architecture to work best, implement a HTTP router in front of the services that routes requests to the correct service. A popular solution is path-based routing:
  • http://platform/auth/* → http://auth-api/*
  • http://platform/transaction/* → http://core-api/*
• Make your automation available on a public GitHub repository with a README on how to get things started.

Don't worry too much about making this production ready. We may discuss production considerations with you later on.

Please spend no more than 1-2 hours on this exercise.

Bonus (Optional)

• Containerise services.
• Apply the Twelve Factor App methodology.