GraphQL - how we use it

Brief talk about GraphQL technology, how we use it at BetterMe and our plans.

Transcript

1. Yehor Kisilov, iOS Engineer @ BetterMe GraphQL How we use it?
2. Origin • Introduced by Facebook in 2012, public release in 2015 • GraphQL Foundation in 2018, hosted by Linux Foundation
3. Reasons • Multiple requests causing app performance problems • Data overfetching • Backend-Frontend coupling
4. Components
5. Components • Schemas and Types • Queries and Mutations
6. Components Schemas and Types
7. Components Queries
8. Components Mutations
9. Pros and Cons
10. Pros • Declarative • Strongly typed • Introspective • Versioning
11. Pros Declarative data fetch
12. Pros Strongly typed • De fi ne the data structure and the information that can be consumed • De fi nitions are written down in a Schema
13. Pros Introspection • Fetch schema using HTTP client • Valid queries and data models on a spot • Documentation
14. Pros Versioning
15. Cons • Lack o ff built-in caching • Query complexity • Maximum depth of query
16. How it works
17. Backend. How it works Technologies • Go • GQLGen for GraphQL layer generation • Neo4J graph database platform
18. Backend. How it works Performance and security • Batch data loading • Cyclomatic query complexity check • Data validation • Error handling
19. Client side. How it works • Feature development starts with schema • Documentation • Code generation for requests • Error handling
20. Client side. How it works Documentation • Stored within schema • Up-to-date according to current schema
21. Client side. How it works Code generation for requests • Inspired by graphql-code-generator@github Schem a + Operations ➡
22. Client side. How it works Error handling • Multiple errors in response • Custom validation and status codes • Handle each error individually
23. Next steps
24. Next steps Persistent queries
25. Next steps Apollo GraphQL Studio