Implementation of DTC property masks.

A property is redacted from the document if the following conditions are met:
 * property has been annotated with a :mask f attribute
 * f is a function
 * (f dtc doc action property-name) is truthy at the time of deferral

Example:
(defn mf
  "Property :y is read-only, disable writing!"
  [dtc doc action property-name]
  (not= :read action))

(def dtc
  (dom-type-collection :name :qwerty
                       :properties {:x (s/string)
                                    :y (s/string :mask mf)
                                    :z (s/string)}))

Useful functions for masking DTC properties.

The collection header adds information about migrations

A persistence layer aimed at MongoDB with versioned collection

Predicates used in a query. They will be translated into a mongo query.

This namespace is copied from com.timezynk.domain.util.schema.validation.