Notes on getting started with GraphQL - working with Eurex data

Although I had heard the term GraphQL (www.graphql.org) before I never took a look at it. As outlined on https://graphql.org/ , GraphQL is a query language and specification for your APIs which was initially developed by Facebook as a more flexible and efficient alternative to REST (See GraphQL: a data query language for some background). 

I started looking at the GraphQL to explore the Eurex T7 Reference Data API.  Eurex is the largest European futures and options market and primary deals in Europe-based derivatives (interest-rate derivatives, equity index and equity derivatives and even more exotic derivatives like volatility derivatives, FX derivatives, etc...)

To learn which queries are supported you can use GraphQL introspection to get information about all available requests, filters and response - below is an example of a Postman request

Another easy way to explore the API which is also outlined on the Eurex Reference data API start page is using the GraphQL Playground for Chrome extension

You can also use graphql-voyager to visually explore GraphQL API as an interactive graph - a live demo environment is available as well where you add your own APIs - GraphQL Voyager (apis.guru)

Related links:

• New free and public reference data API (Eurex)
• Azure Tips & tricks - how to use GraphQL on Azure (Youtube) using HotChocolate 
• GraphQL: the big picture (Pluralsight) - good overview in a little over 1 hour by @AdhithiRavi