Each contract block will current produce a single ...

# http4k

[dave]

Each contract block will current produce a single swagger file. Because of the setup of the DSL, you can't extract them as a sub contract block in the same way that you can with a standard routes block.

But you can nest contract blocks inside standard routes blocks (and routes blocks can be composed) to create a tree structure where some of the routes are covered by a contract and some aren't / we do this in the example by combining the API contract with static routing and the website routes.

[Nezteb]

In my case I have

/users which has like 12 routes on top of it
/organizations which has 10
/workspaces that has 10

And I could make one giant chain of

routes += ... * 32

But I was hoping to do that only 3 times and have each of those nested route sets in separate files, but still produce a single Swagger file

[dave]

you could combine them into lists and combine the lists..

[dave]

(we do this with versioned routes (so we have objects creating lists of /v1 and a /v2 routes)

[Nezteb]

Oooooo that’s not a bad idea. Me gusta.

[Nezteb]

"/api/v1" bind contract {
    renderer = OpenApi(ApiInfo("My great API", "v1.0"), Jackson)
    descriptionPath = "/swagger.json"
    security = AuthSecurity(::authFilter, contexts)
    for (route in organizationsRoutes) {
        routes += route(contexts)
    }
},

[Nezteb]

it looks terrible in a Slack thread, but since each route takes the RequestContexts object, this is the only way i could find to do it

[dave]

where route is (RequestContext) -> ContractRoute? looks fair enough

[dave]

you could also do it with a map for l33t functional skillz: routes.map { it(contexts) }

[Nezteb]

oh man, that’s why i asked this question: https://kotlinlang.slack.com/archives/C0922A726/p1556047869115400

[Nezteb]

routes doesn’t seem to have a .map option

[Nezteb]

I assume because Appendable doesn’t inherit from any of the standard Kotlin collection types

[dave]

sorry - it should be:

[dave]

routes += organizationsRoutes.map { it(contexts) }

[dave]

(Appendable does have:

operator fun plusAssign(t: Collection<T>) { all += t }

) 🙂

[dave]

as an aside, applying a list of functions to a particular value is quite a neat trick:

listOf(::addOne, ::addTwo, ::addThree).fold(1, { acc, next -> next(acc) })

[Nezteb]

Mind blown.

[Nezteb]

I didn’t realize that .map had a it available

[dave]

once of the nice thing about Kotlin is that it's very consistent, for example:

data class Age(val i: Int)
    val ages: List<Age> = listOf(1, 2, 3).map(::Age)

[dave]

because the constructor is just another function reference...