Example of using GraphQL with InterSystems IRIS with Graphene, SQLAlchemy and Flask.

What are the goals of this example?

Create a sample Employee, Department data model in InterSystems IRIS
Implement a GraphQL server to query and modify data

What do you need to install?

Git
Docker (if you are using Windows, make sure you set your Docker installation to use “Linux containers”).
Visual Studio Code + InterSystems ObjectScript Extension Pack
Python

Setup

Run an InterSystems IRIS Community edition instance:

docker compose build
docker compose up -d

Create a Python virtual environment for this project:

# create a local venv environment
python3 -m venv .venv

# activate venv
source .venv/bin/activate

# install dependencies
pip3 install -r requirements.txt

Create some sample data

Open an interactive Python session and run a method to initialize your data model and insert some data.

cd graphql-server
python

from models import db_session, engine, Base, Department, Employee
# create tables
Base.metadata.create_all(bind=engine)
# create some data
from app import init_data
init_data()

Run GraphQL server

There is a GraphQL server implementation ready for you to test:

graphql-server/models.py - defines the database schema. It includes the models for Employee and Department.
graphql-server/schema.py - GraphQL schema definition using Graphene. It includes queries and mutations for creating data.
graphql-server/schema-relay.py - Another GraphQL schema definition using Graphene but using a relay approach that supports pagination.
graphql-server/app.py - sets up the Flask application and /graphql and /graphql-relay endpoints for both schemas (relay and not relay).

cd graphql-server
python app.py

Test your GraphQL implementation

You can import collection_iris-graphql-demo.json in Postman or ThunderClient for VS Code and check the output.

There is also a GraphiQL UI available at http://localhost:5000/graphql