GraphQL and Django

Anton Pirker

Django Meetup Vienna - November 7th 2017

GraphQL

• System for fetching and manipulating data from/on a server
• Query language + type system + server component
• Instead of having many dump API endpoints (REST), just one smart endpoint (GraphQL).

What does it look like?

 GET request to /graphql/                                           Reponse JSON

What does it look like?

 GET request to /graphql/                                           Reponse JSON

What does it look like?

 GET request to /graphql/                                           Reponse JSON

What does it look like?

 GET request to /graphql/                                           Reponse JSON

GraphQL summarized:

• Ask for what you need, get exactly that
• Get many resources in a single request
• Decoupling of client app and server API development

Implementation

• Python implementation: Graphene 
• Django integration: graphene-django
• In browser IDE: GraphiQL (demo)

Django integration

Define your models as always

  ingredients/models.py

Django integration

Add a GraphQL schema

  ingredients/schema.py

Introducing 'Relay'

• Convention on how to specify your schema
• Standardized way to pagenate, refetch and manipulate objects
• Specification: facebook.github.io

More on 'Relay'

• Graphene has complete support for Relay
• If a schema has connections, edges and nodes, its Relay.
• Client side lib for creating react relay apps: react-relay

Pro

• It's cool
• It can speed up development
• It make changing client app way easier
• It minimizes amount of data transferred

Cons

• It's from Facebook
• Possible patent problems: https://www.theregister.co.uk/2017/09/26/facebook_license_surgery_on_react/

Conclusion

Thank's!

anton@ignaz.at - www.anton-pirker.at