Feature: Param Aggregation Draft

[ghost]

#10 shares the problem when there's a meaningful amount of parameters on the handler function, this feature aims to reduce the number of parameters aggregating them into new objects.

Current:

get("/user/{userId}")
    .param(String.class)
    .query("page", Integer.class)
    .query("limit", Integer.class)
    .query("order", String.class)
    .handle((userId, page, limit, order) -> { /* */ });

with param aggregation:

get("/user/{userId}")
    .param(String.class)
    .aggregate().query("page", Integer.class).query("limit", Integer.class).query("order", String.class).as(Pagination::new)
    .handle((userId, pagination) -> { /* */ });

[Florian-Schoenherr]

aggregate seems like it overlays with DDD terminology, I would propose "tuple" if we really use this API.

But instead, we could have queryObject and paramObject.

get("/user/{userId}")
    .param(String.class)
    .queryObject("page limit order", Pagination.class)
    .handle((userId, pagination) -> { /* */ });

I don't have experience with fluent interfaces and the above example is highly optimistic, so this might not even work. Mainly I would want the API to be pretty close to the current one, so delimiting the strings by a space would be easiest. We don't need to specify the types of the query params again, because they're already defined inside Pagination.class.

[VaughnVernon]

I like your idea to have a queryObject() but I think that queryParameters() is better. That is better than aggregate(). So maybe like this:

• queryParameters("page;limit;order", Pagination.class) or queryParameters("page:limit:order", Pagination.class)
• The media type separator is ; so that is probably the better choice
• I think having a delimiter is better than spaces because it makes it more obvious what the words mean

You are welcome to give it a go when you can in a month or so. This is almost 2.5 years old so it is obviously not urgent.

[Florian-Schoenherr]

@VaughnVernon delimiter ✔️ Semicolon is probably best, I had ? in mind (because queries), but these would naturally be more like ?...&. & would make more sense than ?. Now I also just read that ; gets used instead of & sometimes, so let's just go for those.

Will see, I think we have more urgent stuff to do 👍