How to create an array in the GraphQL’s argumment as GraphQL Code First Approach

In GraphQL Code First Approach I am trying to pass the same argumment for createUser in createManyUser but I want to pass it as an array to create many users at once. I searched a lot but couldn’t find it in GraphQL Code First Approach.

The Code

export const createUser = {
    type: userType,
    args: { // This work fine
        email: { type: string },
        username: { type: string },
        firstName: { type: string },
        lastName: { type: string }
    },
    resolve: async (_, args, { userAuth }) => {
        try {
            const user = await db.models.userModel.create(args);
            return user;
        } catch (error) {
            throw Error(`${error.message}`)
        }
    }
}

export const createManyUser = {
    type: new GraphQLList(userType),
    args: [{ // Here I made an array [] but it dose not work so here is my problem
        email: { type: string },
        username: { type: string },
        firstName: { type: string },
        lastName: { type: string }
    }],
    resolve: async (_, args, { userAuth }) => {
        try {
            const user = await db.models.userModel.bulkCreate(args);
            return user;
        } catch (error) {
            throw Error(`${error.message}`)
        }
    }
}

Answer

You can’t just put the args options in an array, to tell GraphQL that you expect a list of things you explicitly need to construct a GraphQLList type.

And you can’t make a mutation field take a list of named things either – you must give the mutation one named argument that expects a list of input objects. So it’ll be

export const createManyUser = {
    type: new GraphQLList(userType),
    args: {
        inputs: { type: new GraphQLList(new GraphQLNonNull(new GraphQLInputObjectType({
//                          ^^^^^^^^^^^                        ^^^^^^^^^^^^^^^^^^^^^^
            name: 'CreateUserInput',
            description: 'Input payload for creating user',
            fields: {
                email: { type: string },
                username: { type: string },
                firstName: { type: string },
                lastName: { type: string }
            }
        })))
    },
    resolve: async (_, args, { userAuth }) => {
        const user = await db.models.userModel.bulkCreate(args.inputs);
//                             ^^^^^^^
        return user;
    }
}

See also this article.