Key Points

References

Key Concepts

Java GraphQL example from Okta

https://developer.okta.com/blog/2020/01/31/java-graphql

spring-ex-java-graphql-sprint-developer.okta.com-How to GraphQL in Java.pdf

REST APIs are hard to design so they serve multiple clients well. As each client has their own needs in terms of data searching, filtering and which fields they want, a traditional REST API will provide a single version of an entity and the client has the responsibility of navigating through multiple endpoints and correlate the data on their side to build the data they want.

GraphQL was developed by Facebook to overcome the shortcomings they found with REST APIs. It’s a query language for APIs and a runtime for fulfilling those queries with your existing data. By providing a complete and understandable description of the data in your API, clients can leverage that and have the power to ask for exactly what they need. By exposing the schema, it makes it easier to evolve APIs over time. Clients can still navigate the schema the way they need even if you add more fields and relations to it.

In this tutorial, I’ll show you how to use Java and Spring Boot to build a GraphQL API. I’ll also show how to test your GraphQL API using Java’s most popular testing library: JUnit 5.

https://graphql.org/

GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data. GraphQL provides a complete and understandable description of the data in your API, gives clients the power to ask for exactly what they need and nothing more, makes it easier to evolve APIs over time, and enables powerful developer tools.

Send a GraphQL query to your API and get exactly what you need, nothing more and nothing less. GraphQL queries always return predictable results. Apps using GraphQL are fast and stable because they control the data they get, not the server.

GraphQL queries access not just the properties of one resource but also smoothly follow references between them. While typical REST APIs require loading from multiple URLs, GraphQL APIs get all the data your app needs in a single request. Apps using GraphQL can be quick even on slow mobile network connections.

GraphQL can use type system definitions

GraphQL APIs are organized in terms of types and fields, not endpoints. Access the full capabilities of your data from a single endpoint. GraphQL uses types to ensure Apps only ask for what’s possible and provide clear and helpful errors. Apps can use types to avoid writing manual parsing code.

GraphIQL tools to build / test queries

Evolve queries dynamically

Add new fields and types to your GraphQL API without impacting existing queries. Aging fields can be deprecated and hidden from tools. By using a single evolving version, GraphQL APIs give apps continuous access to new features and encourage cleaner, more maintainable server code.

Potential Value Opportunities

Potential Challenges

Candidate Solutions

Step-by-step guide for Example

sample code block

Recommended Next Steps

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