Moving a production API from REST & Microservices to GraphQL

GraphQL has many advantages over RESTful APIs. A lot of companies start thinking about migration paths for adopting GraphQL, which not only come with technological but also with organisational challenges!
Karol Wyszynski and Bogdan Nedelcu from Lokalleads (http://www.lokalleads.com/) will tell us about their adventure migrating a backend infrastructure composed of several microservices around a Java web application to GraphQL. Among other topics, they will talk about why (and when) GraphQL is a good choice, how exactly their migration was carried out and the effects it had for their team on a technological and organisational level.

Transcript

1. GraphQL in Production Lokalleads GmbH Hackescher Markt 4 10178 Berlin Germany
2. About us 16.10.17 2 Karol Wyszynski Co-Founder & CTO karol.wyszynski@lokalleads.de LinkedIn: www.linkedin.com/in/karol-wyszynski Bogdan Nedelcu Software-Developer bogdan.nedelcu@lokalleads.de
3. 16.10.17 3 Lokalleads
4. Lokalleads 16.10.17 4 B2B Service provider for craftsman with > 800 customers - Real-time calculator for complex quotation - Lead channel tracking(phone, email, showrooms) - Online Marketing SaaS
5. Lokalleads 16.10.17 5 Founded in 2013 - 35+ employees - 8 applications - 7 developers - 4 programing languages
6. The Journey to GraphQL 6 1. Why: Motivation 2. How: Transition 3. How: Challenges 4. What: Result
7. 7 Motivation
8. Motivation – Legacy Infrastructure 16.10.17 8 Frontend Backend Frontend Backend Frontend Java Php Java Ruby Java ReactJS Frontend Frontend Frontend Backend Backend Backend
9. Motivation - Legacy Application Stack 16.10.17 9 - Mostly MVC(Spring/Rails) with REST Endpoints - Server-Side rendered HTML with Ajax calls - One React JS Front End Client
10. Motivation - Requirements 16.10.17 10 - Complex UI - Public API - Faster Development - Reduce integration effort - Reduce project onboarding - Performance
11. Motivation - Solutions? 16.10.17 11 Complex UI - Experience with React.JS for over a year - Future Implementation in most of the clients - Developer team React knowledge
12. Motivation - Solutions? 16.10.17 12 Public API - Pure REST standard is hard to implement - Unique URI´s, request methods has to have a meaning(PUT or POST?) - Need a Gateway for security and performance /product or /products PUT or POST which Content-Type ?
13. Motivation - Solutions? 16.10.17 13 Integration effort - Deficient tolling: Postman - Documentation
14. Motivation - Solutions? 16.10.17 14 Faster Development - Parallelize front-end and backend development - Communication and Transparency
15. Motivation - Solutions? 16.10.17 15 Better Performace - Network road-trips - Reduce payload
16. Motivation – Solution 16.10.17 16 Frontend Java Frontend Php Frontend Frontend Frontend Frontend Java Ruby Node GraphQL API Node
17. Motivation – Technical Risk 16.10.17 17 Non industrial Standard API • Fastest growing community • Strong reference implementation by Facebook
18. Motivation – Technical Risk 16.10.17 18 Lack of experience - Hired Professional Support for inital setup - Team Training
19. Motivation – Technical Risk 16.10.17 19 • REST as a supplement All usecases covered?
20. 16.10.17 20 Transition
21. 16.10.17 21
22. Transition: Incremental Adoption 06.07.17 lokalleads 22 lokalleads Frontend Backend Frontend Backend Frontend Backend Frontend Backend Frontend Backend GraphQL Frontend Backend
23. Transition: Client App Based 06.07.17 lokalleads 23 lokalleads Frontend Backend Frontend Backend Frontend Backend Frontend Backend Frontend Backend Frontend Backend GraphQL
24. Transition: Client Requirements 06.07.17 lokalleads 24 lokalleads - Concurrent request - Different data sources - Reactive: On user action more requests
25. Transition: Development Process Schema Design Backend && Frontend Production
26. Transition: GraphQL Schema Prefer building a Graph-QL schema that describes how clients use the data, rather than mirroring the legacy database schema.
27. Transition: GraphQL Schema
28. Transition - Mock Data REST responses were used as mock data.
29. Transition: Development Process Schema Design Production Development
30. Transition: Client App Based View 1 View 1 View 1 View 1 View 1 GraphQL Server Resolver2 Resolver 2 Resolver1
31. Transition - GraphiQL
32. Transition - Apollo Client
33. Transition - Voyager
34. Transition: Development Process Schema Design Production Backend && Frontend
35. Transition: Production Tips
36. Transition: Production Tips
37. Challenges: Thinking in Graphs 06.07.17 lokalleads 37 In the REST implementation data is modeled in terms of network services. /campaigns /campaigns_and_metrics /campaigns_and_statistics
38. Challenges: Thinking in Graphs 06.07.17 lokalleads 38 With GraphQL, you model your business domain as a graph. /campaigns /campaigns_and_metrics /campaigns_and_statistics
39. Challenges: Thinking in Graphs 06.07.17 lokalleads 39
40. Challenges - Thinking in Graphs 06.07.17 lokalleads 40
41. Challenges - Schema Agreement 06.07.17 lokalleads 41 - Development starts with the Schema - Hard types force the team to agree before hand
42. 06.07.17 lokalleads 42 Result
43. Results - Release Speed 2Xrelease speed***. - Parallelized workflow - Better Tooling - Frontend team Autonomy
44. Results: Release Speed 2Xless onboarding time. - Clean API - Tooling - Hard Typed
45. Results: Release Speed 2Xless time documenting. - Code as Documentation - GraphiQL as API inspector
46. Results: Release Speed 10Xdev happiness. - Tooling - YPWNT
47. 06.07.17 lokalleads 47 Many Thanks!