Is there a way to send multiple mutations in one request? I'm not seeing any way to specify a list o...

# apollo-kotlin

[rocketraman]

Is there a way to send multiple mutations in one request? I'm not seeing any way to specify a list of mutations in the client API.

[mbonnin]

You're most likely looking for query batching? To make everything in a single round trip?

[rocketraman]

Yup

[mbonnin]

This issue has been opened for a while 🙈

[rocketraman]

Though some backends will actually put multiple mutations sent in a request into a single transaction. For example, Hasura.

[mbonnin]

Yea, this is kind of the point, right?

[rocketraman]

Well, that's not specified by the gql spec afaik, so I guess its implementation specific.

[rocketraman]

Do you have a pointer to the issue?

[mbonnin]

Yep but if the backend doesn't do any optimization, I was under the impression that using HTTP2 pipelining would reduce latency without any increased network overhead?

[mbonnin]

That'd be the issue: https://github.com/apollographql/apollo-android/issues/513

[mbonnin]

Overall, query batching a double edge sword because your mutation become as slow (or fast) as the slowest mutation in the batch

[rocketraman]

Makes sense about HTTP2 pipelining, where supported at least. Yeah, understood about the batching -- my case will require async and awaitAll anyway.

[rocketraman]

Do you know what sav007 means by:

And with client batching (via aliases) seems to me like a workaround.

[rocketraman]

(https://github.com/apollographql/apollo-android/issues/513#issuecomment-401940577)

[mbonnin]

I'm guessing the idea was to merge the queries client side and use aliases if requesting two fields with the same name

[rocketraman]

Ah. Yeah, obviously not a solution for mutations.

[mbonnin]

About the hasura use case, what about a big mutation?

mutation {
  updateUser() {}
  addPost() {}
  ...
}

[mbonnin]

You can request any number of root fields in a mutation

[rocketraman]

I need to do the same mutation multiple times e.g.:

mutation {
  updateUser() {}
  updateUser() {}
  ...
}

[rocketraman]

And its a list of unknown length

[mbonnin]

Aliases would fix the "multiple times" thing

[mbonnin]

mutation {
  user1: updateUser() {}
  user2: updateUser() {}
  ...
}

[mbonnin]

Not the "arbitrary length" thing

[rocketraman]

Yup, and passing in the parameters for that is annoying, as I need to alias all of those too.

[mbonnin]

Yep. Usually, I would expect a mutation that takes a list of inputs there:

[mbonnin]

mutation($inputs: [UserInputs]) {
  updateUsers($inputs)
}

[rocketraman]

Yeah, Hasura supports inserts with that model. Let me check if they can do updates like that too...

[rocketraman]

No, only a where parameter to update multiple, and it has to be the same update for all matching rows.