Building an open source GraphQL Kotlin library is ...

# opensource

[Marc Knaup]

Building an open source GraphQL Kotlin library is fun. Anyone interested in joining? 😄
I know there is one already, but, you know… diversity. And fun 🙂

[Dominaezzz]

I've been considering building a multiplatform one, mostly around the codegen side for the client. (Haven't really use GraphQL before.)

[Marc Knaup]

Mine is multiplatform and supposed to cover almost everything that the JS reference implementation does.

[Dominaezzz]

But I'd be interested in contributing if you start something.

[Marc Knaup]

No codegen yet though.
Would love to see a compiler plugin at some point. For client & server.

[Marc Knaup]

https://github.com/fluidsonic/fluid-graphql
Still messy as everything is work-in-progress and API far from final. Even the TODO is outdated 😄

[Dominaezzz]

Ha! Just how I like it. 😁

[Marc Knaup]

😂

[Dominaezzz]

Looks like you have a parser so far right? To parse server schemas.

[Marc Knaup]

yes, parses queries and schemas

[Marc Knaup]

just no extensions yet

[Dominaezzz]

Nice, that should be enough to actually generate client side stuff.

[Marc Knaup]

You want to generate Kotlin code from server schema?

[Marc Knaup]

I guess simple generation is easy with KotlinPoet.

Compiler plugin would be nicer but also far more difficult.

[Dominaezzz]

Yeah, like data classes and stuff.

[Marc Knaup]

I always wonder what is nicer to have:
• Generated types for each schema only
• Generated types for each query to a schema (because fields can be absent and you may not want to make ALL fields nullable for that reason)
In the second case they could share a common interface.

[Dominaezzz]

Hmm, that's a good point. Can make it a configuration with "reasonable defaults".

[Marc Knaup]

True, it’s also possible to offer both and let the user decide.

[mbonnin]

Hi, just in case, apollo-android has an issue open to support native and multiplatform: https://github.com/apollographql/apollo-android/issues/1455

[mbonnin]

It might not be that far actually. IIRC, one of the biggest JVM dependency was okhttp but the generated models would still be usable without the runtime

[Marc Knaup]

I guess Apollo does way more than GraphQL if it needs anything related to HTTP 🙂

[mbonnin]

Mostly for subscriptions and cache support but most of the codegen is usable without the HTTP parts

[mbonnin]

What would a compiler plugin bring compared to plain codegen ?

[Marc Knaup]

Changes to GraphQL document/schema automatically change code and vice versa - if needed.
It would be part of the normal compilation rather than relying on command line tools or Gradle integration.

[wakingrufus]

@Dariusz Kuc works on https://github.com/ExpediaGroup/graphql-kotlin

[Marc Knaup]

I’ve seen that but it’s almost completely different from what I want to achieve.

Most importantly:
• no reflection
• no automatic schema-generation from Kotlin classes (at least at runtime - maybe through a compiler plugin)
And they’re focused on the server.

I want to have everything around GraphQL in my library - not the client/server logic around it.
• .graphql file parsing (requests & schemas)
• .graphql file generation
• Kotlin DSL for creating schemas and requests
• request execution & validation, independent of the environment
• tools for working with GraphQL ASTs

[Dariusz Kuc]

cool project

[Dariusz Kuc]

just an fyi - graphql-kotlin-client (generates the type safe client based on the graphql query and target schema) is WIP and should be available in 2.0.0 release (no tentative date yet)

[Dariusz Kuc]

as for the kotlin native query execution -> that is something that we want to tackle eventually in graphql-kotlin as well (currently it relies on graphql-java) but there is no ETA on this

[Dariusz Kuc]

also take a look at https://github.com/aPureBase/KGraphQL