Clojure validation with Metis

gistfile1.clj

(ns app.controllers.validation
  (:require [app.views.a :as a-view]
            [metis.core :as metis]))

;; Validates that the required environment keys are present
(metis/defvalidator :environment-validator [[:core-url :db :auth-token] :presence ])

(metis/defvalidator :preview-body-validator [[:type :filter :template :index ] :presence ])
(metis/defvalidator :preview-request-validator [:body :preview-body-validator ])

(defn validate-request
  [request request-validator ok-function]

  (let [validation-result (into
                            (request-validator request)
                            (environment-validator request))]
    (if (empty? validation-result)
      (ok-function request)
      (a-view/bad-request validation-result))))