GraphQL with Spring Boot

Slides from the presentation at CareerCon Kariera IT in Cracow

Transcript

1. GraphQL with Spring Boot Kariera IT Kraków 02.12.2017 Krzysztof Pawłowski krzysztof.pawlowski@merapar.com | krzychpawlowski
2. About me • Senior Java Developer @ Merapar Technologies • Coder, Lecturer (PJATK), Java Trainer (infoShare Academy) • 7+ years of experience in Java Development • using GraphQL for a year now • E-mail: krzysztof.pawlowski@merapar.com • Twitter: krzychpawlowski
3. REST not so restful? GET /author/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment
4. REST not so restful? GET /author/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment {
 id: 1,
 name: “Krzysztof”,
 email:”k@example.com“,
 bio: “java dev”, blogEntriesIds: [1, 2]
 }
5. REST not so restful? GET /author/:id GET /author/:id/blogEntry/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment
6. REST not so restful? GET /author/:id GET /author/:id/blogEntry/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment {
 id: 1, title: “GraphQL”,
 authorId: 1, commentsIds: [1, 2]
 }
7. REST not so restful? GET /author/:id/blogEntry/:id/comments GET /author/:id GET /author/:id/blogEntry/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment
8. REST not so restful? GET /author/:id/blogEntry/:id/comments GET /author/:id GET /author/:id/blogEntry/:id <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment {
 id: 1,
 author: “anonymous”,
 comment: “super!”
 }
9. While in GraphQL… authors(filter : {id : 1 }) {
 name
 blogEntries {
 title
 comments {
 comment
 }
 }
 } <<class>>
 Author Long id String name String email String bio List<BlogEntry>
 blogEntries <<class>>
 BlogEntry Long id String title List<Comment> comments <<class>>
 Comment Long id String author String comment
10. What is GraphQL? “GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data.” — http://graphql.org
11. What is GraphQL? “GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data.” — http://graphql.org Declarative
 Ask for what you need, get exactly that
12. What is GraphQL? “GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data.” — http://graphql.org Declarative
 Ask for what you need, get exactly that Compositional
 Get many resources in a single request
13. What is GraphQL? “GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data.” — http://graphql.org Declarative
 Ask for what you need, get exactly that Compositional
 Get many resources in a single request Strongly Typed
 Describe what’s possible with a type system
14. GraphQL query authors { # queries can have comments! name email blogEntries { title } }
15. GraphQL query authors { # queries can have comments! name email blogEntries { title } } { "data": { "authors": [ { "name": "author 1", "email": "Python dev", "blogEntries": [ { "title": "blog entry 1" }, { "title": "blog entry 3" } ] }, { "name": "author 2", "email": "Java dev", "blogEntries": [ { "title": "blog entry 2" }, { "title": "blog entry 4" } ] } ] }
16. GraphQL query - filter authors(filter : {id : 1 }) { name email blogEntries { title } }
17. GraphQL query - filter authors(filter : {id : 1 }) { name email blogEntries { title } } { "data": { "authors": [ { "name": "author 1", "email": "Python dev", "blogEntries": [ { "title": "blog entry 1" }, { "title": "blog entry 3" } ] } ] } }
18. GraphQL mutation mutation addAuthorMutation($authorInfo: addAuthorInput!) { addAuthor(input : $authorInfo) { id name bio email } } { "authorInfo": { "id": 1, “name" : "Krzysztof Pawlowski", "bio" : "java dev", "email" : "krzysztof.pawlowski@merapar.com" }
19. GraphQL mutation mutation addAuthorMutation($authorInfo: addAuthorInput!) { addAuthor(input : $authorInfo) { id name bio email } } { "authorInfo": { "id": 1, “name" : "Krzysztof Pawlowski", "bio" : "java dev", "email" : "krzysztof.pawlowski@merapar.com" } { "data": { "addAuthor": { "id": 1, "name": "Krzysztof Pawlowski", "bio": "java dev", "email": 
 “krzysztof.pawlowski@merapar.com" } } }
20. GraphQL schema type Author {
 id: Long! name: String bio: String email: String
 blogEntries: [BlogEntry] }
 
 type BlogEntry { id: Long! title: String! comments: [Comment] } type Comment { id: Long! author: String comment: String }

21. GraphQL schema type Author {
 id: Long! name: String bio: String email: String
 blogEntries: [BlogEntry] }
 
 type BlogEntry { id: Long! title: String! comments: [Comment] } type Comment { id: Long! author: String comment: String }
 type Query { authors(id: Long!): Author blogEntries(id: Long!): BlogEntry comments(id: Long!): Comment } type Mutation { addAuthor(author: Author!): Author updateAuthor(author: Author!): Author deleteAuthor(author: Author!): Author … }
22. GraphQL schema type Author {
 id: Long! name: String bio: String email: String
 blogEntries: [BlogEntry] }
 
 type BlogEntry { id: Long! title: String! comments: [Comment] } type Comment { id: Long! author: String comment: String }
 type Query { authors(id: Long!): Author blogEntries(id: Long!): BlogEntry comments(id: Long!): Comment } type Mutation { addAuthor(author: Author!): Author updateAuthor(author: Author!): Author deleteAuthor(author: Author!): Author … } schema { query: Query mutation: Mutation }
23. Other benefits of GraphQL ‣flexibility ‣one end-point ‣self-documenting (strong typing and schema) ‣query validation ‣easy to implement consumer-driven contracts
24. Client and documentation
25. Spring Boot Starter for GraphQL ‣adding Maven dependency creates GraphQL controller under
 /v1/graphql <dependency> <groupId>com.merapar</groupId> <artifactId>graphql-spring-boot-starter</artifactId> <version>1.0.2</version> </dependency> ‣adding new queries and mutation is a matter of implementing GraphQlFields interface
26. Demo https://github.com/krzysztof-pawlowski/GraphQLwithSpringBoot
27. Problems with GraphQL ‣HTTP caching ‣Unpredictable execution ‣No handling for file upload ‣Authorisation and authentication
28. Future of GraphQL
29. Future of GraphQL
30. Future of GraphQL
31. Future of GraphQL
32. Thank you! Questions? krzysztof.pawlowski@merapar.com | krzychpawlowski