graphql.AssertException when using graphql-java-tools (5.6.1) with apollo federation-jvm

[marmys]

Hi

I'm trying to use apollo federation-jvm together with graphql-java-tools (5.6.1)
https://github.com/apollographql/federation-jvm
This is a library that "federate" graphql-java schema so that this schema can be used later by apollo federation gateway.
https://www.apollographql.com/docs/apollo-server/federation/introduction/

federation-jvm works with graphql-java but does not work with graphql-java-tools.
When I try to run it with graphql-java-tools i got an error:

Caused by: graphql.AssertException: All types within a GraphQL schema must have unique names. No two provided types may have the same name.
No provided type may have a name which conflicts with any built in types (including Scalar and Introspection types).
You have redefined the type 'Query' from being a 'GraphQLObjectType' to a 'GraphQLObjectType'
	at graphql.schema.GraphQLTypeCollectingVisitor.assertTypeUniqueness(GraphQLTypeCollectingVisitor.java:105) ~[graphql-java-13.0.jar:na]
    at graphql.schema.GraphQLTypeCollectingVisitor.visitGraphQLObjectType(GraphQLTypeCollectingVisitor.java:38) ~[graphql-java-13.0.jar:na]
	at graphql.schema.GraphQLObjectType.accept(GraphQLObjectType.java:174) ~[graphql-java-13.0.jar:na]
	at graphql.schema.TypeTraverser$TraverserDelegateVisitor.enter(TypeTraverser.java:71) ~[graphql-java-13.0.jar:na]
	at graphql.util.Traverser.traverse(Traverser.java:147) ~[graphql-java-13.0.jar:na]
	at graphql.schema.TypeTraverser.doTraverse(TypeTraverser.java:58) ~[graphql-java-13.0.jar:na]
	at graphql.schema.TypeTraverser.depthFirst(TypeTraverser.java:50) ~[graphql-java-13.0.jar:na]
	at graphql.schema.TypeTraverser.depthFirst(TypeTraverser.java:38) ~[graphql-java-13.0.jar:na]
	at graphql.schema.SchemaUtil.allTypes(SchemaUtil.java:42) ~[graphql-java-13.0.jar:na]
	at graphql.schema.GraphQLSchema.<init>(GraphQLSchema.java:102) ~[graphql-java-13.0.jar:na]
	at graphql.schema.GraphQLSchema.<init>(GraphQLSchema.java:37) ~[graphql-java-13.0.jar:na]
	at graphql.schema.GraphQLSchema$Builder.build(GraphQLSchema.java:411) ~[graphql-java-13.0.jar:na]
	at com.apollographql.federation.graphqljava.SchemaTransformer.build(SchemaTransformer.java:134) ~[classes/:na]

As I investigated this is because when graphql-java-tools creates schema it passes every type as additionalTypes.
See SchemaParser.kt line 129

return SchemaObjects(query, mutation, subscription, (objects + inputObjects + enums + interfaces + unions).toSet(), codeRegistryBuilder)

4th argument is used as additionalTypes and graphql-java-tools puts every type in it including "Query" type.

In graphql-java additionalTypes are only types that are not referenced from the top level operations.

See SchemaGenerator.java (graphq-java 13.0) line 362

/**
 * We build the query / mutation / subscription path as a tree of referenced types
 * but then we build the rest of the types specified and put them in as additional types
 *
 * @param buildCtx the context we need to work out what we are doing
 *
 * @return the additional types not referenced from the top level operations
 */
private Set<GraphQLType> buildAdditionalTypes(BuildContext buildCtx) {

To get example that does not work:
use federation-jvm example
https://github.com/apollographql/federation-jvm/tree/master/spring-example/src/main/java/com/apollographql/federation/springexample

with modifications:

• add graphql-java-tools 5.6.1 to pom.xml
• simplify graphql schema in inventory.graphql to

    type Query {
      aQuery: String!
    }

• add simple resolver for this query

    package com.apollographql.federation.springexample;
    import com.coxautodev.graphql.tools.GraphQLQueryResolver;
    public class QueryResolver implements GraphQLQueryResolver {
        public String aQuery() {
            return "aValue";
        }
    }

• modify InventorySchemaProvider class:

    @Component
    public class InventorySchemaProvider extends DefaultGraphQLSchemaProvider implements 
    GraphQLSchemaProvider {
        public InventorySchemaProvider(@Value("classpath:schemas/inventory.graphql") Resource sdl) throws Exception {
            super(Federation.transform(buildSchema(sdl)).build());
        }

        private static GraphQLSchema buildSchema(Resource sdl) throws Exception {
            SchemaParserBuilder parserBuilder = com.coxautodev.graphql.tools.SchemaParser.newParser();
            parserBuilder.schemaString(CharStreams.toString(new InputStreamReader(sdl.getInputStream(), UTF_8)));
            parserBuilder.resolvers(new QueryResolver());
            return parserBuilder.build().makeExecutableSchema();
        }
    }

[larslorenzen]

Hi, got the same problem when trying to use graphql-java-tools and federation-jvm in a ktor project.

Reduced it to the minimum amount of code:

import com.apollographql.federation.graphqljava.Federation
import com.coxautodev.graphql.tools.SchemaParser

fun main() {
    val schemaBuilder = SchemaParser.newParser().file("schema.graphqls")
    schemaBuilder.resolvers(UserResolver())
    val schema = schemaBuilder.build().makeExecutableSchema()
    val transform = Federation.transform(schema).build()
    println(transform.toString())
}

schema {
    query: QueryType
}

type QueryType {
    users: [User]
}

type User {
    id: ID!
    username: String!
}

it fails with the same exception.

Exception in thread "main" graphql.AssertException: All types within a GraphQL schema must have unique names. No two provided types may have the same name.
No provided type may have a name which conflicts with any built in types (including Scalar and Introspection types).
You have redefined the type 'QueryType' from being a 'GraphQLObjectType' to a 'GraphQLObjectType'
	at graphql.schema.GraphQLTypeCollectingVisitor.assertTypeUniqueness(GraphQLTypeCollectingVisitor.java:105)
	at graphql.schema.GraphQLTypeCollectingVisitor.visitGraphQLObjectType(GraphQLTypeCollectingVisitor.java:38)
	at graphql.schema.GraphQLObjectType.accept(GraphQLObjectType.java:174)
	at graphql.schema.TypeTraverser$TraverserDelegateVisitor.enter(TypeTraverser.java:71)
	at graphql.util.Traverser.traverse(Traverser.java:147)
	at graphql.schema.TypeTraverser.doTraverse(TypeTraverser.java:58)
	at graphql.schema.TypeTraverser.depthFirst(TypeTraverser.java:50)
	at graphql.schema.TypeTraverser.depthFirst(TypeTraverser.java:38)
	at graphql.schema.SchemaUtil.allTypes(SchemaUtil.java:42)
	at graphql.schema.GraphQLSchema.<init>(GraphQLSchema.java:102)
	at graphql.schema.GraphQLSchema.<init>(GraphQLSchema.java:37)
	at graphql.schema.GraphQLSchema$Builder.build(GraphQLSchema.java:411)
	at com.apollographql.federation.graphqljava.SchemaTransformer.build(SchemaTransformer.java:134)
	at ApplicationKt.main(Application.kt:12)
	at ApplicationKt.main(Application.kt)

[gabrielbs]

I'm getting the same running the federation example

[hendryluk]

Same for me too :(

[hendryluk]

I've debugged into this and found what seems to be the problem:
GraphQLSchema that gets generated seems to have additionalTypes that includes the Query and Mutation objects (i.e. it duplicates schema.getQueryType() and schema.getMutationType()).

This causes the said exception whenever another library attempts to build another schema on top of it i.e. via GraphQLSchema.newSchema(schema).build(), because it would detect the duplication

[hendryluk]

The workaround is to clear the additionalTypes before you pass it into Federation.transform, i.e.: schema = GraphQLSchema.newSchema(schema).clearAdditionalTypes().build()