Schema: Is there away to be able to specify case-insensitive enum (string)?

[Wei Xun Ter]

Currently s/enum will check for strict equivalent in a set of string enum. Is there away that we can have a case-insensitive version?

(def schema (s/enum ["SUCCESS", "FAILURE"]

i.e. "Success" can be coerce validated to "SUCCESS"

One way I was thinking is to create a new schema:

(defrecord CaseInsensitiveEnumSchema [vs]
  Schema
  (spec [this] (leaf/leaf-spec (spec/precondition this #(contains? vs (.toUpperCase %)) #(list vs %))))
  (explain [this] (cons 'case-insensitive-enum vs)))

(defn case-insensitive-enum
  "A value that must be = to some element of vs."
  [& vs]
  (EnumSchema. (set vs)))

That works for validation i.e. (s/validate schema "Success") => "Success".

But it doesn't work for generating swagger automatically.

Thanks.

[Jason Wolfe]

The custom schema type seems like a good solution.  I imagine you just have to tell swagger how to generate it, but I'm not sure how that works.

Another option if you're OK normalizing would be to use a regular enum schema plus coercion to normalize the case of the values up front. 

-Jason

[Tommi Reiman]

For Swagger, there is a protocol to extend, example here: https://github.com/metosin/ring-swagger/blob/master/src/ring/swagger/json_schema.clj#L174-L176