Currency conversion API

Currency conversion API is a GraphQL API that provides a small service converting Euro to US Dollar and vice-versa.

Access to convert is protected with Access Key that can be generated by creating a new project:

mutation {
  createProject(project: {name: "Project"}){
    name
    accessKey
  }
}

To access convert query use project's accessKey as an Authorization header:

convert(from: EUR to: USD amount: 10) {
  timestamp
  rate
  result
}

1. Tech stack

• Golang
• GraphQL
• Docker
• Docker Compose

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2. Dependencies

External golang packages

• Go library for building GraphQL servers – https://github.com/99designs/gqlgen
• Structured logger for Go (golang) – https://github.com/sirupsen/logrus
• Go library for UUID generation – https://github.com/google/uuid

External services

• Foreign exchange rates and currency conversion JSON API – https://fixer.io

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3. Contribution

Use https://github.com/99designs/gqlgen to get basic knowledge

3.1. Development

1. Do change in .graphqls files
2. Run generator to generate new or update code according to new schema

$ make regenerate

3. Implement resolvers according to your needs

3.2. Running locally

Execute command

$ make run

Run the playground in browser: http://localhost:3000

3.3. Running Unit Tests

Execute command

$ make test

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4. Containerized environment

To build a container Docker and Docker-Compose has to be installed:

• https://docs.docker.com/get-docker/
• https://docs.docker.com/compose/install/

To run an application using docker-compose use next command:

$ docker-compose up

Run the playground in browser: http://localhost:3000