1. Introduction
2. What's in the project
3. Running the application 3.1 Build - test - package from the source code 3.2 Run using docker or docker-compose 3.3 Run the Docker image from DockerHub
4. About the code

This project is a microservice that serves the following API endpoints:

• Output the current time (GMT+1).
• Validate a VAT input and return corresponding country code.
• Convert currency input. Note: The free plan of the Currency Layer API only allows to get real-time rates from USD to desired currencies. Therefore, the source currency of the conversion feature is always USD.

• Source code that you can review.
• A micro-service that you can build, test & run yourselves.
• Documentation, where relevant.
• Incorporation of software engineering best-practices and design-patters where relevant.
• Test coverage to ensure code-quality.
• Service running on port 8081.
• BONUS: Autogenerated Swagger documentation.
• BONUS: Dockerfile with multi-layer build and relevant README instructions.
• BONUS: Incorporate embedded DB/caching for API endpoints.

You can either run the application by building, testing and running the project from the source code, OR spin-up a container using docker and docker-compose, OR use the Docker image provided on DockerHub to run a container.

Prerequisites: Maven 3.6.1, Java 11

• Download source code or clone it using git clone https://github.com/rafikbelas/currensee.git
• Go to the project folder cd currensee
• Run the following command mvn clean
• Test the application by running mvn test
• Run the application by running: mvn spring-boot:run. This will start the application on port 8081 http:https://localhost:8081/api/
• To test the API endpoints, head to the auto-generated Swagger documentation

Prerequisites: docker ordocker-compose

• Download source code or clone it using git clone https://github.com/rafikbelas/currensee.git
• Go to the project folder cd currensee
• Option 1 (Using docker-compose): Run the following command docker-compose up or docker-compose up -d. This will build a new image using the and spin-up a container.
• Option 2 (Using docker): Run the following commands docker build -t currensee:latest . && docker run -dp 8081:8081 currensee. This will build a new image if not existant and run a container from it.
• To test the API endpoints, head to the auto-generated Swagger documentation

Prerequisites: docker

• Run the following command docker run -dp 8081:8081 rafikbelas/currensee. This will download the currensee image from the DockerHub and run it.
• To test the API endpoints, head to the auto-generated Swagger documentation

• controller : entry-point of each API. calls the appropriate service(s) with the received parameters and returns the corresponding response.
• service : Services that hold the business logic, independently from external APIs, in case those are changed. Eventually calls other services in the service > api related to an external API.
• service > api: Services that call external APIs, separated from business logic.
• dto: Object responses returned by controller or received by external services.
• validator: Custom validators
• configuration : Custom configuration
• exception: Custom exceptions and a GlobalExceptionHandler to handle all exepctions thrown by the controller.

The external APIs used are CurrencyLayer and CloudMersive. The CloudMersive API provides a ready SDK that was used in the service to call the API.

The GlobalExceptionHandler provides exception handling to each error thrown by the controller and returns a custom response with

• status
• message
• timestamp
• debug message (Optional)
• subErrors (Optional): list of fields that cause the error.
  • field
  • rejecteValue
  • message

Errors regarding the external APIs and API Keys are returned as INTERNAL_SERVER_ERROR for now.