Proposal: GraphQL Composite Schemas Working Group

[benjie]

There's a lot of different ways of combining multiple GraphQL schemas together to form a larger composite schema, and the wide variety of options can make it challenging to design schemas in a way that will be easy to compose later. To name but a few approaches:

• Schema merging and stitching (various implementations in many languages)
• GraphQL modules and other "extend type"-based approaches
• Federation (Apollo's v1 and v2, Mercurius, WunderGraph, Hot Chocolate, etc)
• Hasura's GraphQL Joins

Though these are all separate solutions to similar problems, there are various concerns that most of them have to consider:

• Identifying the schemas to join
• Discovering/defining the relationships between the types/schemas
• Schema manipulation to avoid conflicts (e.g. renaming types/fields)
• Declaring which schemas "own" a particular type, and detecting conflicts
• Detecting breaking changes
• Actually fetching the relevant data, and combining it to fulfil the GraphQL request
• etc

Not wanting to cause an XKCD#927 situation…

… but, it feels like it would be of benefit to the ecosystem at large if there were a shared specification that covers a few of these needs.

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I propose we set up a working group encompassing people working on these problems and start some discussions around forming a common specification that covers a few of these needs.

I'm not suggesting that we aim to write a full specification for "The One True Way To Build A Big GraphQL Schema From A Number Of Smaller GraphQL Schemas" (TOTWTBABGSFANOSGS) ─ the different approaches listed above tend to solve slightly different problems and have different pros and cons for different situations. Instead, I propose a smaller specification that describes the common ground that everyone can build and innovate on top of. My hope is that this will help the entire ecosystem iterate more rapidly; and will also give GraphQL users more choice, enabling the best solutions for each given problem set to float to the surface more easily.

Initially, I think it would be great to get representatives from the various projects working in this space together to discuss what a spec might look like, and what it should contain. I propose the name "GraphQL Composite Schemas Working Group" to keep it as vendor neutral as possible.

If you're interested, comment below!

[yaacovCR]

I would love to join the group.

[rivantsov]

add me too, thanks!

[timsuchanek]

Thanks for kicking this off @benjie! I'd love to join!

[saihaj]

Yes I would love to join this!

[hayes]

I'm interested in working on this

[mcollina]

I’m in

[jensneuse]

CEO of WunderGraph here. I really like the idea and would love to participate/contribute!
If this spec look right, we'd be more than happy to contribute a MIT licensed Gateway implementation in go/golang and add it to graphql-go-tools.

[StarpTech]

Long overdue! Thanks for raising this. I'm looking forward!

[Urigo]

So happy this is happening, I would love to join and support, thanks for leading it @benjie !

[xuorig]

Count me in 👍

[grillorafael]

Hey, I know I am not active here or anything but I've been using GraphQL in an enterprise context for about 2 years and relying on Federation / Stitch for a while. Have a special interest on Subscriptions and how people develop distributed schemas independently as well.

Any way I can join and be part of this working group?

[benjie]

Working groups tend to be open to all; this WG doesn't exist yet, but if/when it does I'll post here with details 👍

(Also thanks everyone for chiming in! I'm raising this at the next GraphQL Spec WG to see if we can make it an official WG 👍 )

[obi1kenobi]

Great idea, would love to join! 🙌

[praveenweb]

@benjie - Great initiative! Would love to participate and contribute to an open spec :)

[hwillson]

Thanks for kick starting this @benjie! Apollo folks would love to attend as well.

[patrick91]

I’m interested too :)

[ndejaco2]

I am interested :)

[notrab]

This is awesome. I'd love to be part of it, and help in any way I can to create some content on this once we have something 😄

[charlypoly]

Interested too, great initiative!

[michaelstaib]

I am in

[benjie]

Thanks for your interest, everyone! I've added everyone to the list that has attended a GraphQL Spec Working Group somewhat recently (since we added GitHub usernames to the agendas); for those that I could not add like this (@hayes @jensneuse @grillorafael @obi1kenobi @patrick91 @ndejaco2 @notrab @charlypoly) once this PR gets merged, please follow up with your own PR to add yourself which will require you to agree to the various GraphQL agreements (see: https://github.com/graphql/graphql-wg#contributing-to-this-repo), then we can get you added!

[grillorafael]

Thank you very much @benjie. I will do that as soon as this PR gets in.

[LunaticMuch]

I am all in, it I can still apply :)

[buger]

Hi there! I'm Head of Engineering at Tyk.io, and we maintain our implementation of Federation algorithm for our GraphQL solution (and it is based a lot on https://github.com/wundergraph/graphql-go-tools).
We defo want to actively participle in this dicussions, and have expertise in this area.
Will raise CLA with our legal team, and try to add our company.

Thanks!

[doomsbuster]

I am interested!

[KoldBrewEd]

Count me in 🙌

[andimarek]

@benjie
Another relevant solution in this space is Nadel: https://github.com/atlassian-labs/nadel

[benjie]

@andimarek Are you or someone from Nadel interested in joining?

[gmac]

I’m game.

[okjulian]

Awesome initiative, would love to contribute ❤️

[linux-jedi]

Interested.

[chikit]

I'm an engineer on the GraphQL server at Meta. Would like to contribute.

[hellobudha]

Will be happy to contribute :)

[ataylormays-duetto]

I'm in! ✋

[bhupatikrish]

Thank you for doing this. I would like to contribute, please count me in.

[fotoetienne]

a smaller specification that describes the common ground that everyone can build and innovate on top of

I think there would be a lot of value in this. In particular having a standard way to define object instance identity (such as @key in Apollo federation, or Node.id in Relay) would go a long way. Thanks for kicking this off @benjie !

[benjie]

Hi folks! This sub-WG has been ratified, so now is the time to open a pull request to add yourself to the list of interested parties (if you're not already there):

https://github.com/graphql/graphql-wg/edit/main/rfcs/CompositeSchemas.md

Next week is busy with the GraphQL conference, but after that I will look at the stated locations of all involved and try and pick an initial meeting time with the hopes as many of you as possible can make it. I will give at least a week's notice by posting in this thread.

Let's do this! 🙌 🚀

[benjie]

First meeting is now scheduled; please see this issue for details: graphql/composite-schemas-wg#1