Array length and type validators.

lib/errapi.rb

@@ -14,8 +14,10 @@ def self.default_config
     Configuration.new.tap do |config|
       config.plugins << Errapi::Plugins::ErrorCodes.new
       config.plugins << Errapi::Plugins::Messages.new
-      config.register_validation :length, Errapi::Validations::Length
+      config.register_validation :array_length, Errapi::Validations::ArrayLength
+      config.register_validation :string_length, Errapi::Validations::StringLength
       config.register_validation :presence, Errapi::Validations::Presence
+      config.register_validation :type, Errapi::Validations::Type
       config.register_condition Errapi::Condition::SimpleCheck
       config.register_condition Errapi::Condition::ErrorCheck
       config.register_location :dotted, Errapi::Locations::Dotted

lib/errapi/plugins/error_codes.rb

@@ -1,5 +1,10 @@
 class Errapi::Plugins::ErrorCodes
   CODES = {
+    array_length: {
+      wrong_length: 'length.invalid',
+      too_short: 'length.tooShort',
+      too_long: 'length.tooLong'
+    },
     presence: {
       nil: 'presence.nil',
       empty: 'presence.empty',
@@ -9,6 +14,9 @@ class Errapi::Plugins::ErrorCodes
       wrong_length: 'length.invalid',
       too_short: 'length.tooShort',
       too_long: 'length.tooLong'
+    },
+    type: {
+      wrong_type: 'type.invalid'
     }
   }
 

lib/errapi/plugins/messages.rb

@@ -1,14 +1,22 @@
 class Errapi::Plugins::Messages
   MESSAGES = {
+    array_length: {
+      wrong_length: 'This array must contain exactly %{check_value} elements but has %{checked_value} elements.',
+      too_short: 'This array must contain at least %{check_value} elements but has only %{checked_value} elements.',
+      too_long: 'This array must contain at most %{check_value} elements but has %{checked_value} elements.'
+    },
     presence: {
       nil: 'This value cannot be null.',
       empty: 'This value cannot be empty.',
       blank: 'This value cannot be blank.'
     },
     string_length: {
-      wrong_length: 'This string must be exactly %{check_value} characters long but has %{checked_value}.',
-      too_short: 'This string must be at least %{check_value} characters long but has only %{checked_value}.',
-      too_long: 'This string must be at most %{check_value} characters long but has %{checked_value}.'
+      wrong_length: 'This string must be exactly %{check_value} characters long but has %{checked_value} characters.',
+      too_short: 'This string must be at least %{check_value} characters long but has only %{checked_value} characters.',
+      too_long: 'This string must be at most %{check_value} characters long but has %{checked_value} characters.'
+    },
+    type: {
+      wrong_type: 'This value is of the wrong type.'
     }
   }
 

lib/errapi/validations/array_length.rb

@@ -0,0 +1,31 @@
+class Errapi::Validations::ArrayLength
+  CHECKS = { is: :==, minimum: :>=, maximum: :<= }.freeze
+  CAUSES = { is: :wrong_length, minimum: :too_short, maximum: :too_long }.freeze
+
+  def initialize options = {}
+    @constraints = actual_constraints options
+  end
+
+  def validate value, context, options = {}
+    return unless value.respond_to? :length
+
+    actual_length = value.length
+
+    CHECKS.each_pair do |key,check|
+      next unless check_value = @constraints[key]
+      next if actual_length.send check, check_value
+      context.add_error cause: CAUSES[key], constraint_value: check_value, constrained_value: actual_length
+    end
+  end
+
+  private
+
+  def actual_constraints options = {}
+    options.dup.tap do |actual|
+      if range = actual.delete(:within)
+        raise ArgumentError unless range.kind_of? Range
+        actual[:minimum], actual[:maximum] = range.min, range.max
+      end
+    end
+  end
+end

lib/errapi/validations/string_length.rb

@@ -1,4 +1,4 @@
-class Errapi::Validations::Length
+class Errapi::Validations::StringLength
   CHECKS = { is: :==, minimum: :>=, maximum: :<= }.freeze
   CAUSES = { is: :wrong_length, minimum: :too_short, maximum: :too_long }.freeze
 

lib/errapi/validations/type.rb

@@ -0,0 +1,12 @@
+class Errapi::Validations::Type
+
+  def initialize options = {}
+    @type = options[:kind_of]
+  end
+
+  def validate value, context, options = {}
+    unless value.kind_of? @type
+      context.add_error cause: :wrong_type
+    end
+  end
+end