Hi, how do you guys apply spec for dates? specifically with clj-time if possible?

I’m using compojure-api

I want to coerce strings to clj-time dates

Dates in general is a can of worms. 🙂 My current attempt is to use strictly ISO 8601 formatted strings when transferring dates over wire. I use regexp to validate the strings at the edges using spec and I do coercion to date instances in business logic if/when needed.

Time will show how much pain this approach causes.

doesn’t inst? predicate just work?

(st/encode inst? (java.util.Date.) st/json-transformer)
; "2019-01-11T13:46:36.469+0000"

(st/decode inst? "2019-01-11T13:46:36.469+0000" st/json-transformer)
; #inst"2019-01-11T13:46:36.469-00:00"

I guess clj-time (joda) would require custom Specs to work. But that should be relatively straightforward to do?

It works but I’d like to convert to clj-time, the spec itself is ok but I can’t make it nice in swagger

ended up using something like https://github.com/metosin/compojure-api/blob/master/test19/compojure/api/coercion/spec_coercion_test.clj

tks all

what does nice in swagger mean?

btw, you can attach the encode & decode functions to specs too:

(s/def ::date
  (st/spec
    {:spec (partial instance? DateTime)
     :type :date-time
     :reason "FAIL"
     :encode/json str->date-time
     :json-schema/default "2017-10-12T05:04:57.585Z"}))

also add swagger hints, like:

(s/def ::date
  (st/spec
    {:spec (partial instance? DateTime)
     :type :date-time
     :reason "FAIL"
     :encode/json str->date-time
     :swagger/type "date-time"
     :json-schema/default "2017-10-12T05:04:57.585Z"}))

oh thats pretty cool

nice means the example value gets generated correctly

e.g. encode and decode namespaces control how the spec gets transformed, json-schema and swagger ns’s are used in the json-schema / swagger transformations

yes

was doing something like

(s/def ::clj-time (s/with-gen #(instance? DateTime (from-string %))
                              #(s/gen #{"2018-01-01" "2018-01-02"})))

adding all the possible data (encoder, decoder, gen, example, swagger-info etc.) means a lot of data, but then again, it’s just data and every bit has it’s own use case.

btw in your example is it encode/json or decode/json

?

btw, the swagger-spec-transformer uses json-schema-spec-transformer under the hoods, so with swagger, it merges the swagger namespaced over the json-schema namespaced.

oh, should be decode/json as it’s string->date. good catch!

👍 we like compojure-api 😉

one more thing @ikitommi, the ::date spec is working but apparently I can’t compose it : (s/def ::somemap (s/map-of ::date ::string))

I can check with s/explain but going to the api it doesn’t conform

@mping map-of doesn't conform keys by default. You need to pass in some option to it, can't recall, but found in it's docstring

it didn’t work; it’s :conform-keys true

but apparently it’s receiving a keyword

I should try disabling wrap-keyword-params

or maybe with the json parser

oh, I would do that in the :decode/json

e.g. take the name if it's a keyword.

got it! working