Initial commit

app/api/v2/validations.rb

@@ -0,0 +1,77 @@
+# frozen_string_literal: true
+
+module API
+  module V2
+    module Validations
+
+      class AllowBlankValidator < Grape::Validations::AllowBlankValidator
+        # Default exception is costructed from `@api` class name.
+        # E.g
+        # @api.base.name  => API::V2::Account::Withdraws
+        # default_message => "account.withdraw.missing_otp"
+        def message(_param)
+          api = @scope.instance_variable_get(:@api)
+          module_name = api.base.parent.name.humanize.demodulize
+          class_name = api.base.name.humanize.demodulize.singularize
+          # Return default API error message for Management module (no errors unify).
+          return super if module_name == 'management'
+
+          options_key?(:message) ? @option[:message] : default_exception(module_name, class_name)
+        end
+
+        def default_exception(module_name, class_name)
+          "#{module_name}.#{class_name}.empty_#{attrs.first}"
+        end
+      end
+
+      class PresenceValidator < Grape::Validations::PresenceValidator
+        # Default exception is costructed from `@api` class name.
+        # E.g
+        # @api.base.name  => API::V2::Account::Withdraws
+        # default_message => "account.withdraw.missing_otp"
+
+        def message(_param)
+          api = @scope.instance_variable_get(:@api)
+          module_name = api.base.parent.name.humanize.demodulize
+          class_name = api.base.name.humanize.demodulize.singularize
+          # Return default API error message for Management module (no errors unify).
+          return super if module_name == 'management'
+
+          options_key?(:message) ? @option[:message] : default_exception(module_name, class_name)
+        end
+
+        def default_exception(module_name, class_name)
+          "#{module_name}.#{class_name}.missing_#{attrs.first}"
+        end
+      end
+
+      # Range validation for pagination tool
+      class Range < Grape::Validations::Base
+        def initialize(*)
+          super
+          @range = @option
+        end
+
+        def validate_param!(attr, params)
+          return unless (params[attr] || @required) && !@range.cover?(params[attr])
+
+          raise Grape::Exceptions::Validation, \
+            params:  [@scope.full_name(attr)],
+            message: "must be in range: #{@range}."
+        end
+      end
+
+      # Greater then zero validation for integers
+      class IntegerGTZero < Grape::Validations::Base
+        def validate_param!(name, params)
+          return unless params.key?(name)
+          return if params[name].to_s.to_i.positive?
+
+          raise Grape::Exceptions::Validation,
+              params:  [@scope.full_name(name)],
+              message: "#{name} must be greater than zero."
+        end
+      end
+    end
+  end
+end