Graphql查询在Apollo Client和graphql-go中出现'Unknown type Int'错误

Question

I've got a graphql server implemented with graphql-go, and I'm using Apollo on the front end. Simple queries without arguments, and mutations using input object types work fine, but for some reason passing a scalar type argument in a query returns the error:

[{"message":"Unknown type \"Int\".","locations":[{"line":1,"column":19}]}]

My use could not be simpler; on the client side, my query is:

export const GET_CLIENT = gql`
  query client($id: Int) {
  client(id: $id) {
    id
    name
  }
}`

which is used in a component like so:

<Query
  query={GET_CLIENT}
  variables={{
    id: 1
  }} />

which resolves to this field on the backend:

// ClientQuery takes an ID and returns one client or nil
var ClientQuery = &graphql.Field{
Type: ClientType,
Args: graphql.FieldConfigArgument{
    "id": &graphql.ArgumentConfig{
        Type: graphql.Int,
    },
},
Resolve: func(p graphql.ResolveParams) (interface{}, error) {
    return p.Context.Value("service").(*model.Service).FindClientByID(id)
},
}

I've tried passing input objects, strings, etc. but it seems that no query arguments, scalar or otherwise are ever satisfied on the backend. I've tried both master and v0.7.5 of graphql-go. Am I missing something? Help very much appreciated, it feels weird for something this basic to be such a huge blocker.