The document outlines the transition of commercetools' public GraphQL API from beta to a production-ready service capable of handling increased traffic. It highlights key developments from 2015 to 2020, focusing on scaling operations, protecting against complex queries, and ensuring API consistency through automation and internal usage feedback. Additionally, it discusses performance optimization strategies and the importance of investments in automation and operations for sustained growth.

1. Bringing a public GraphQL API
from beta to production ready
at scale
Yann Simon

2. What is commercetools
commercetools
API
/products
/carts
…
merchant
center
Single page
app
Mobile app
cloud
functions
cloud queues
Server
Web / app

3. GraphQL @ commercetools
from 2015 to 2020

4. 2015
• July 2015: Facebook published the first draft of the GraphQL specification
• October 2015: first experimental GraphQL support at commercetools

5. 2015 - 2020
• from 2018, more & more GraphQL traffic

6. 2020

7. What happened?
• Scaling up
• operation
• development of GraphQL API (speed, quality)
• performances

8. Scaling up operations

9. Protection against complex queries
{
products {
results {
id
version
}
}
}
needs more resources to run
{
products {
results {
id
version
productType {
name
}
}
}
}
fetch the productType

10. Protection against malicious queries
• Query complexity analysis based on schema and resolution strategies
• Too complex queries are blocked
• more info:
• https://www.apollographql.com/blog/securing-your-graphql-api-from-
malicious-queries-16130a324a6b/
• https://sangria-graphql.github.io/learn/#protection-against-malicious-
queries

11. Add info to HTTP log entries
method path status code
GET /products 200
POST /carts 201
GET /reviews/79323 404
DELETE /product-discounts/47393 500

12. Add info to HTTP log entries
method path status code
POST /graphql 200
POST /graphql 200
POST /graphql 200
POST /graphql 200
operation
type
top level fields complexity
number of
errors
Query
products,
category
650 0
Mutation cart 140 0
Query review 340 0
Mutation productDiscount 500 1

13. Metrics

14. Slow logs
• log slow queries
• ‼ do not log sensitive data ‼

15. Scaling up operations
• protection against malicious queries
• more info to http logs
• metrics
• slow logs
• confidence in operating a GraphQL API at scale

16. Scaling up GraphQL API
development

17. Internal usage
• Internal applications are using the GraphQL API
(merchant center, demo shop)
• shorter feedback loops
• improve API design
• Frontend and Backend working together

18. API consistency - schema validations
• General conventions for API consistency
• Internal validations based on the schema
[ERROR] Caused by: sangria.schema.SchemaValidationException: Schema does not pass validation. Violations:
[ERROR] Output object 'Category' contains a localized string field named 'name' which does not follow the 'xxx' !-> String + 'xxxAllLocales' !-> List(LocalizedString) naming convention.
[ERROR] at sangria.schema.SchemaValidationRule$.validateWithException(SchemaValidationRule.scala:42)
[ERROR] at sangria.schema.Schema.<init>(Schema.scala:939)

19. Automation of GraphQL Schema
• Our REST API is following a CQRS architecture
• different models for queries and mutations
• Based on this model, generate GraphQL schema
• Use schema introspection to test what is exposed

20. Automation of API release notes
• Production schema !== in development schema
• Based on the differences, generate markdown file for public release notes

21. schema deprecations

22. Scaling up API development
• Faster feedback loops
• internal usage
• Faster development
• generating GraphQL types from REST API models
• schema validations for API consistency
• public release notes
• Using deprecations to evolve
• Graphql coverage is almost complete

23. Scaling up performances

24. more tools for external developers
• Expose query complexity as HTTP header
https://docs.commercetools.com/api/graphql#query-complexity
• Profiling

25. query optimization
Client Server Database
Optimize payload
Servers to servers
Migrating our Apple WatchOS Commerce App to GraphQL

26. query optimization
Client Server Database
Optimize query
Do not select all fields
Performance optimization (GraphQL meetup in Berlin)

27. Inspect live servers

28. Scaling up performances
• Give tools for users of the API
• Optimize database queries based on GraphQL query
• Inspect live servers
• Continuous process

29. Evolving a public Graph API
from experimental to production ready
needs investments in different areas

30. Invest in automation

31. Invest in operations

32. Continuous improvement

33. Involve everyone

34. Being production ready for
more GraphQL traffic