TV Shows REST vs GraphQL API

This demo project, used for my talk called "Modernize your APIs, go for GraphQL!" is intended to show the differences between REST and GraphQL APIs.

REST API

• First we have a basic REST API
• Then we'll add a GraphQL API based on the same data model

The REST API is accessible at http://localhost:8080/api/v1/tvshows

[Source code: rest-api git branch]

GraphQL API

• The GraphQL API is added on top of the REST API version.
• A Schema is described in the tv-shows-schema.graphqls. It describes a few types, queries, and mutations.

The GraphQL API is accessible at http://localhost:8080/graphql

And the GraphiQL tool is accessible at http://localhost:8080/graphiql

[Source code: graphql-query-mutation git branch]

GraphQL Subscription

• A SchemaBuilder class adds a Subscription root type to the previously created .graphls schema.
• Add reactive communication between client and server using web-sockets and RxJava
• Subscriptions use the ws-subscription endpoint for web-sockets
• Have a look at the client at http://localhost:8080/
  • Click on the button to connect to the web-socket
  • Enter a TV Show ID (for example: 1)
  • Click on Send button to send the subscription request
  • Open another tab with GraphiQL and send a few mutations to vote for a TV Show
  • Go back to the previous browser tab and see that data has been updated

This demonstrates the subscription concept, but we'll need to:

• replace server side database polling by real events fired for example from JPA @PostPersist and @PostUpdate callbacks.
• stop looking at AverageRating updates after web-socket disconnection.
• display multiple TvShows ratings on the web page (each line would be fed from a given web-socket)
• Use user sessions to send messages to (stop throwing average rating updates to everyone).

[Source code: graphql-subscription git branch]

Appendix

Every TV Show description has been taken from JustWatch and IMDB websites