Add GraphQL support

[sdeleuze]

There seems to be 2 way of supporting GraphQL:

• https://github.com/graphql-java/graphql-java-spring
• https://github.com/ExpediaDotCom/graphql-kotlin

We need to see which one is the more relevant.

[FVershinin]

I started working on it.

[sdeleuze]

Awesome, thanks!

[sdeleuze]

@FVershinin Any update? I recently found https://github.com/ExpediaDotCom/graphql-kotlin which is pretty interesting. Are you using it or another library?

[FVershinin]

Yes. I am using this library to generate graphql schema.

Current status:

1. Added kotlin-dsl for "ExpediaDotCom/graphql-kotlin"
2. Added support operations "query" and "mutation"
3. Added support for webmvc and webflux
4. Added dsl to configure graphql
5. Added support graphiql https://github.com/graphql/graphiql

sample: https://github.com/FVershinin/spring-fu/blob/spring-graphql/samples/kofu-servlet-graphql/src/main/kotlin/com/sample/Application.kt

my branch: https://github.com/FVershinin/spring-fu/tree/spring-graphql

Now I am trying to integrate graphql-java with WebSocket, Flux WebSocket and RSocket.

[FVershinin]

There seems to be 2 way of supporting GraphQL:

• https://github.com/graphql-java/graphql-java-spring
• https://github.com/ExpediaDotCom/graphql-kotlin

We need to see which one is the more relevant.

They are resolving two different tasks:

1. ExpediaDotCom/graphql-kotlin focuses on generate graphql schema.
2. graphql-java/graphql-java-spring focuses on HTTP execution.

[sdeleuze]

Thanks for your feedback and the PR. I would be super interested to see how RSocket and GraphQL could be used together!

[sdeleuze]

Another source of inspiration from @tgirard12 https://github.com/tgirard12/graphql-kotlin-dsl

[sdeleuze]

Solving this issue should probably leverage the new Spring GraphQL support incubating in https://github.com/spring-projects-experimental/spring-graphql.