Schema Merging Issue with @oneOf Directive

[Noejoaquin]

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---

Describe the bug
I am developing a new feature using the new @oneOf directive. We currently merge our schemas, but when I attempt to perform the following:

const { loadSchemaSync } = require("@graphql-tools/load");
const { GraphQLFileLoader } = require("@graphql-tools/graphql-file-loader");
const { printSchemaWithDirectives } = require("@graphql-tools/utils");

try {
    console.log('Loading schema files...')
    const schemaFiles = loadSchemaSync("./globToGetSchemas/**/schema.graphql", {
        loaders: [new GraphQLFileLoader()],
    });
    console.log('Beginning write of merged queries...')  
    fs.writeFileSync("merged.graphql", printSchemaWithDirectives(schemaFiles));
} catch (error) {
    console.log("Error: ", error)
}

The following error arises:

The schema in question:

input SomeInput @oneOf {
	scenarioOne: InputOne 
	scenarioTwo: InputTwo
}

input InputOne {
	fieldOne: String!
	fieldTwo: String!
}

input InputTwo {
	fieldOne: String!
}

To Reproduce
Attempt to merge a graphql schema using the @oneOf directive

Expected behavior
Schemas using this directive to be merged without issue

Environment:

• "@graphql-tools/graphql-file-loader": "^8.0.1", "@graphql-tools/load": "^8.0.2",:
• NodeJS: v20.11.1

Thank you for taking a look into this! 🙏

[ardatan]

@oneOf is not part of the GraphQL spec. So you have to add the definition of the directive by yourself just like any other custom directive.

[Noejoaquin]

Ahh okay. I see. I misunderstood where things were and clearly only skimmed things. Got a little lost in all the chains of discussion. My bad and thanks!!

[Urigo]

@Noejoaquin are you using OneOf in production today or have a use case for it?
I would love to meet and learn more about your use case