Canaan Advisors Test

Task description

• Your task is to develop both the backend API and the web-based interface that will enable users to place orders. The API should be implemented using Golang, while the web-based interface should be developed using Next.js. You are free to choose a database of your preference. It is important to prioritize the backend implementation, as it will be evaluated more extensively.
• The user interface should allow users to browse available restaurants, view menus in a tree structure, add items to their cart, and place orders. The wireframe below provides three simple pages as a guide. After an order is placed, it should be sent to the backend API for processing. The API should then store the order in a database and send a notification to both the restaurant owner and the delivery driver.
• The application should include the following features:
  • User authentication and authorization
  • Management of restaurants and menus
  • Order management
  • Notification system
• Please note that while you are not required to fully implement the authentication flow, you will need to create three distinct roles: user, driver, and restaurant owner. Restaurant owners should be able to add, delete, or update items in the menu, while both the restaurant owners and drivers should receive notifications in real-time when orders are placed.

Prerequisites

1. Create google folders by using mkdir ./libs/google and mkdir ./libs/google/api
2. Download annotations.proto and http.proto files from googleapis github repo: https://github.com/googleapis/googleapis/blob/master/google/api
3. Add those files to ./libs/google/api
4. golang 1.19

How to run local

• Run services and workers: docker compose up -d

TODO tasks

• Integrate APIs and FE
• Implement and integrate order, management database (Postgres)
• Implement authentication flow (Firebase)
• Implement Kafka and ksql for notification
• Implement Redis to cache client id
• Implement API gateway: forwarder and authenticator
• Implement role based permission
• Wireframe for mobile
• Implement notification

Technologies and Frameworks

• Languages: Go, typescript
• FE Framework: NextJS
• SDK: temporal.io
• Clean architecture
• Network: gRPC, HTTP
• Docker, docker compose
• Database: postgres, redis
• Cloud server: AWS, Firebase

Architecture

System Design

Wireframe

Services

• API gateway:

  • Structure: DDD and Clean architecture
  • Features:
    • Forwarder
    • Aggregator
    • Authenticator
  • Database: redis
  • API design: RPC and REST, google.api wrapper
  • Language: go 1.19

• Order service:

  • Structure: DDD and Clean architecture
  • Features:
    • Create orders
    • Manage order lists
  • Database: postgres
  • API design: RPC and REST, google.api wrapper
  • Language: go 1.19
  • Message broker: kafka

• Notification service:

  • Structure: DDD and Clean architecture
  • Features:
    • Receive message
    • Send message
    • Websocket
  • Message broker: kafka
  • API design: RPC and REST, google.api wrapper
  • Language: go 1.19

• User service:

  • Structure: DDD and Clean architecture
  • Features:
    • Authentication
    • Manage users and roles
  • Database: Firestore
  • API design: RPC and REST, google.api wrapper
  • Language: go 1.19

• Management service:

  • Structure: DDD and Clean architecture
  • Features:
    • Manage restaurants
    • Manage menu, categories, items
  • Database: postgres
  • API design: RPC and REST, google.api wrapper
  • Language: go 1.19

• Message broker:

  • Kafka: pub-sub service
  • ksqlDB: stream kafka event for monitoring and debugging

Directory structure

📁 canaanadvisors-test
|__ 📁 api // adapter layer
|__ 📁 config
    |__ .env
    |__ app.go
|__ 📁 core 
    |__ 📁 activities // temporal activities
    |__ 📁 app // application layer
    |__ 📁 models // entitiy layer
    |__ 📁 workflows // temporal workflows
|__ 📁 infra
    |__ logger.go
    |__ temporal.go
|__ 📁 libs
|__ 📁 proto
|__ 📁 worker // temporal workers
|__ 📁 web // FE
|__ docker-compose.yml
|__ go.mod
|__ go.sum
|__ README.md

References

• https://blog.cleancoder.com/uncle-bob/2012/08/13/the-clean-architecture.html
• Transcoding of HTTP/JSON to gRPC: https://adevait.com/go/transcoding-of-http-json-to-grpc-using-go
• https://docs.temporal.io/