QueryParams, Links, Pagination, and Included Serialization

Hi there! Great library, I had a few questions after reading the docs and reading through some of the test cases. Some things aren't immediately apparent so I'd love some insight into this or some recommendations.

What's the recommended way to construct links? If I use the jsonapi_model! macro there doesn't seem to be a good way of shoving in additional links without some additional work (such as spreading out the document into a new document). If that's the recommended approach then I'd love to see some docs around that (willing to help!)
Same question as above for pagination attributes
What's the recommended way to not include models from a relationship in the included field? If the consumer hasn't specified the "include" parameter then I don't want to expand the response but I don't think I care if I overfetch to get the information for the relationship. In other words, if I provide the nested struct, I don't care that it gets filtered out at the end besides the type and id for the link
QueryParams-- how are they meant to be used in conjunction with the models that we produce? It's sort of the same question as above and it goes to this part of the spec here. This one isn't exactly something that I think I'll ever need (most api consumers just grab everything anyways) but some clarification or some tests would help

On a similar vein to question 3, consider the following hierarchy (not entirely valid code)

use models::spam::Spam;

struct Bar {
    id: String,
    spams: Option<Vec<Spam>>
}

jsonapi_model!(Bar; 'bars'; has many spams);

struct Foo {
    id: String,
    bars: Option<Vec<Bar>>;
}

jsonapi_model!(Bar; 'foos'; has many bars);

let bars = vec![Bar::new(), Bar::new(), Bar::new()];
let foo = Foo::new(&bars)

foo.to_jsonapi_document()

This produces the following output (attributes sections omitted since we don't have any):

{
    "data": {
        "type": "foos",
        "id": "1234",
        "relationships": {
            "bars": {
                "data": [
                    { "type": "bars", "id": "31" },
                    { "type": "bars", "id": "32" }
                    { "type": "bars", "id": "33" }
                ]
            }
        }
    },
    "included": [        
        {
            "type": "bars",
            "id": "31",
            "relationships": {
                "spams": {
                    "data": []
                }
            }
        }
        ....rest of the bars
    ]
}

But this makes it seem like I don't have any spams at all, which is totally valid to the perspective of this library because I have't provided that information. This could also be a part of the standard itself, since I've only read through a few of the relevant sections of the spec, but it doesn't seem like included attributes have to provide relationship information. However, even given that limitation, this lib rightfully adds my nested information into the included section of the document. Is it possible to omit the relationship field on nested attributes?

Example JSON doc of what I mean:

{
    "data": {
        "type": "foos",
        "id": "1234",
        "relationships": {
            "bars": {
                "data": [
                    { "type": "bars", "id": "31" },
                    { "type": "bars", "id": "32" }
                    { "type": "bars", "id": "33" }
                ]
            }
        }
    },
    "included": [        
        {
            "type": "bars",
            "id": "31",
            "relationships": {
                "spams": {
                    "data": [
                        { "type": "spams", "id": "uuid-84848" }
                    ]
                }
            }
        }
        ....rest of the bars
        {
            // This shouldn't exist
            "type": "spams",
            "id": "uuid-84848",
            "attributes": {
                ...attrs
            }
        }
    ]
}

Again I'd love to help out with figuring this out since this lib seems very focused and very well made!

Edit: I think part of the last point could be fixed if serde's skip_if directive was taken into account for the relationship fields? I can skip serializing the main attributes but not any relationship fields, they just default to an empty slice.

michiel / jsonapi-rust

QueryParams, Links, Pagination, and Included Serialization #73