This project contains a GraphQL API that interacts with a PostgreSQL database using the Sequelize ORM. I used the graphql-sequelize library to easily create a graphql API out of the Sequelize models. In addition to this I used dataloader-sequelize to ensure the same data isn't fetched from the database twice.
I chose to use GraphQL because it is becoming the industry standard for API development. There is a rich ecosystem of tools making development fast and easy. I chose to use graphql-sequelize because it not only makes it easy to set up GraphQL resolvers, but it does work for you to keep queries efficient. For example, it only includes fields requested by the client in the query to the database. This is possible on your own but takes some extra work.
- Docker
- Node v13 (optional)
To start the database and run the api server, run the following command:
docker-compose upBy default, some data is created and added to the database. If you want to run the project without seed data, change SEED_DATA to "false" in docker-compose.yml. To test the api, you can open http://localhost:4000 in your browser and execute queries in the GraphQL Playground. An example query that expands all the data is below:
{
programs {
id
name
description
sections {
id
name
description
overviewImage
order
activities {
id
content
options {
id
text
}
}
}
}
}
In addition to GraphQL Playground, I added a test.js which adds some data and queries it to simulate a client. To run the test file in the docker container, run docker ps and copy the modern-health-assignment_api's ID. Then paste it in the command below:
CONTAINER=<paste id here>
docker exec -it $CONTAINER sh -c "npm test"
You can run these tests locally as well provided you have node installed and there aren't dependency version issues with node and npm. I used node v13.13.0 during development. To run the tests locally, just run npm i followed by npm test.
The database is set up using Sequelize.sync for simplicity. In the real world, migrations should be used to set up the database.