GraphQL.js Node/Express: How to pass object as GraphQL query argument - node.js

Question

My goal is to be able to pass an object as an argument in a GraphQL query.
Goal:
{
accounts (filter:
{"fieldName": "id",
"fieldValues":["123"],
"filterType":"in"}){
id
}
}
Error:
"message": "filterType fields must be an object with field names as keys or a function which returns such an object."
I've tried a few different approaches but this seems to be the closest to the potential solution.
Schema:
const filterType = new GraphQLObjectType ({
name: 'filterType',
fields: {
fieldName: { type: GraphQLString },
fieldValues: { type: GraphQLString },
filterType: { type: GraphQLString },
}
})
const QueryType = new GraphQLObjectType({
name: 'Query',
fields: () => ({
accounts: {
type: new GraphQLList(accountType),
args: {
filter: { type: new GraphQLInputObjectType(filterType) },
},
resolve: (root, args, { loaders }) => loaders.account.load(args),
},
}),
});

Answer 1

I have found the solution here.
https://github.com/mugli/learning-graphql/blob/master/7.%20Deep%20Dive%20into%20GraphQL%20Type%20System.md#graphqlinputobjecttype
Schema:
const filterType = new GraphQLInputObjectType({
name: 'filterType',
fields: {
fieldName: { type: GraphQLString },
fieldValues: { type: GraphQLString },
filterType: { type: GraphQLString },
}
})
const QueryType = new GraphQLObjectType({
name: 'Query',
fields: () => ({
accounts: {
type: new GraphQLList(accountType),
args: {
filter: { type: filterType },
},
resolve: (root, args, { loaders }) => {
return loaders.account.load(args)},
},
}),
});
Problem was in the query, I had the both the keys and values as strings in the object argument.
Correct Query:
{
accounts(filter: {fieldName: "id", fieldValues: "123", filterType: "in"}) {
id
}
}

Answer 2

You don't define filterType as an object type then wrap it in an input type, you literally create it as an input type:
const filterType = new GraphQLInputObjectType({
name: 'filterType',
fields: {
fieldName: { type: GraphQLString },
fieldValues: { type: GraphQLString },
filterType: { type: GraphQLString },
}
})
const QueryType = new GraphQLObjectType({
name: 'Query',
fields: () => ({
accounts: {
type: new GraphQLList(accountType),
args: {
filter: { type: filterType },
},
resolve: (root, args, { loaders }) => loaders.account.load(args),
},
}),
});
You'll also want to declare its type at query time, as illustrated in #piotrbienias's answer.