Federation with dataloader grouping

[amtineo]

What happened?

I have multiple graphs that are federated with an Apollo Router. For example, I have a sample query of:

graph1field(id: "some-uuid") {
	id
        graph2field {
             id
             name
             graph3field {
                   id
                   name
             }
        }
}

The results of graph3field are not grouped to the proper graph2field. Let's say there are many graph3fields that belong to the last graph2field result, the results are not grouped to where they should be. Sample response:

{
  "data": {
      "graph1field": {
           graph2field {
                id
                name
                graph3field: []
           },
           graph2field {
                id
                name
                graph3field: [
                    id
                    name
                ]
           },
           graph2field {
                id
                name
                graph3field: [
                    id
                    name
                ]
           }
      }
   }
}

Most of the time the graph3field are mixed into the incorrect graph2field.

What did you expect?

I expect the correct grouping to happen. When I remove the dataloder referenced in your examples: dataloadgen, everything is in the correct group. However, the n+1 problem comes back.

I expect the following response always:

{
  "data": {
      "graph1field": {
           graph2field {
                id
                name
                graph3field: []
           },
           graph2field {
                id
                name
                graph3field: []
           },
           graph2field {
                id
                name
                graph3field: [
                   {
                      id
                      name
                   },
                   {
                      id
                      name
                   }
                ]
           }
      }
   }
}

Minimal graphql.schema and models to reproduce

Unfortunately, I can't share the real schema.

versions

• go run github.com/99designs/gqlgen version?
  v0.17.49
• go version?
  go version go1.22.0 windows/amd64