Cryptocurrency Prices Api

This application serves as a proxy backend server exposing api for cryptocurrency prices information.

Meta info

Application showcases knowledge of:

• Java programming language
• Spring framework
  • Application setup and initialization
  • Annotation utilization
    • Controller and Service definition
    • Exposed requests mapping
    • Dependency injection (on constructor)
    • Cross origin handling
• Swagger (for application specification)
• General
  • Services defined as interfaces with separate implementation
  • REST calls
    • GET with request parameters
  • Calls to 3rd party api
  • Error handling
  • Helpers and utility classes with mostly static content
  • Having git commit messages readable
• Concepts
  • Separation of concerns
  • "N-tier architecture"
    • Controllers expose api endpoints
    • (Business) Logic and calls to 3rd party api is found inside services
• Operations
  • Setting environment variables (for production and development differentiation)
  • Deploying application

Requirements

1. Java - 11.x
2. Maven - 3.x.x

Development server

1. Build and run the backend app using maven

   mvn package
   java -jar cryptocurrencypricesapi-0.0.1-SNAPSHOT.jar

   Alternatively, you can run the app without packaging it, using:

   mvn spring-boot:run

2. Provide environment variables:

• CRYPTO_API_URL - url of the 3rd party api containing cryptocurrency prices information (example: https://sandbox-api.coinmarketcap.com)
• CRYPTO_API_KEY - this key will be used as header (key: X-CMC_PRO_API_KEY) when making call to the 3rd party api