Lessons Learned from Integrating Django & GraphQL

A few lessons learned while working with GraphQL & Django.

Transcript

1. LESSONS LEARNED LESSONS LEARNED FROM INTEGRATING DJANGO & FROM INTEGRATING DJANGO & GRAPHQL GRAPHQL Created by Krzysztof Żuraw
2. WHO AM I? WHO AM I? PYTHON AND JAVASCRIPT DEVELOPER PYTHON AND JAVASCRIPT DEVELOPER AT AT BASED IN WROCŁAW. BASED IN WROCŁAW. STXNEXT STXNEXT
4. LESSON 1: GRAPHQL LESSON 1: GRAPHQL IS COOL IS COOL IF YOU KNOW HOW TO USE IT IF YOU KNOW HOW TO USE IT
5. TECHNOLOGY STACK TECHNOLOGY STACK
9. ASK FOR WHAT YOU NEED ASK FOR WHAT YOU NEED GET RESULTS GET RESULTS { allActors{ lastName } } { "data": { "allActors": [ { "lastName": "Travolta" }, { "lastName": "Jackson" }, } }
10. GET MANY RESOURCES IN A GET MANY RESOURCES IN A SINGLE REQUEST SINGLE REQUEST { film(id: 1) { title actors { firstName lastName } } }
11. { "data": { "film": { "title": "Pulp Fiction", "actors": [ { "firstName": "John", "lastName": "Travolta" }, { "firstName": "Samuel L.", "lastName": "Jackson" }, ]}}
12. DATA MUTATION DATA MUTATION mutation CreateFilm { createFilm(film: { title: "My cool title" }) { title id } } { "data": { "createFilm": { "title": "My cool title", "id": 123 } } }
13. mutation UpdateFilm { updateFilm(film: { title: "Totaly different title" }) { title } } { "data": { "updateFilm": { "title": "Totaly different title", } } }
16. LESSON 2: GRAPHENE-PYTHON LESSON 2: GRAPHENE-PYTHON class Film(graphene.ObjectType): class Meta: interfaces = (relay.Node, ) title = graphene.String() actors = graphene.List(Actor) air_date = graphene_datetime.DateTime() rating = graphene.Int()
17. { "name": "film", "description": "The ID of the object", "args": [ { "name": "id", "description": null, "type": { "kind": "NON_NULL", "name": null, "ofType": { "kind": "SCALAR", "name": "ID", "ofType": null } }, "defaultValue": null } ], "type": { "kind": "OBJECT", "name": "Film", "ofType": null }, "isDeprecated": false
18. CONCLUSION CONCLUSION PYTHON HAS A GREAT GRAPHQL PYTHON HAS A GREAT GRAPHQL LIBRARY LIBRARY BUT BUT You have to be aware that it is a new library
20. LESSON 3: GRAPHRELATED FIELD LESSON 3: GRAPHRELATED FIELD Why? Almost like ForeginKey in Django but without existence checks
21. # one microservice class Film(models.Model): title = models.CharField(max_length=100) air_date = models.DateField() actor = GraphRelatedField('Actor') # another microservice class Actor(models.Model): name = models.CharField(max_length=100) # usage actor_name = film.actor.name
22. CONCLUSION CONCLUSION WE WANT TO HAVE BETTER WE WANT TO HAVE BETTER COMMUNICATION BETWEEN COMMUNICATION BETWEEN MICROSERVICES MICROSERVICES JUST TO JUST TO Merge them together
24. LESSON 4: NUMBER OF LESSON 4: NUMBER OF REQUESTS REQUESTS Inspired by Django ORM `prefetch_related` Fetch list of objects using one HTTP query and place them in thread-safe attribute inside a context.
25. CACHING CACHING HTTP Headers caching
26. SET CACHING HEADERS TO SET CACHING HEADERS TO INFORM INFORM For how long cache the response? When there is need for refetch data for different users using the `Vary` header
27. CACHE POLICY CACHE POLICY Short cache times - less than 1 minute
28. CONCLUSION CONCLUSION USING CACHING BY VARY HEADER AND USING CACHING BY VARY HEADER AND PREFETCHING OBJECTS IS GOOD IDEA PREFETCHING OBJECTS IS GOOD IDEA
30. LESSON 5: AUTHENTICATION LESSON 5: AUTHENTICATION What? JWT Why?
31. CONCLUSION CONCLUSION CHOOSING JWT WAS A GOOD IDEA - IT CHOOSING JWT WAS A GOOD IDEA - IT ALLOWS US TO STORE ADDITIONAL INFO ALLOWS US TO STORE ADDITIONAL INFO
32. LESSON 6: FRONTEND TOOLING LESSON 6: FRONTEND TOOLING
33. CONCLUSION CONCLUSION A LOT OF NEW LIBRARIES - NOT ALWAYS A LOT OF NEW LIBRARIES - NOT ALWAYS MATURE MATURE
35. THIS IS THE END THIS IS THE END Thank you My blog: krzysztofzuraw.com My twitter: @krzysztof_zuraw