Simpler structure.

lib/errapi.rb

@@ -14,10 +14,12 @@ def self.default_config
     Configuration.new.tap do |config|
       config.plugins << Errapi::Plugins::ErrorCodes.new
       config.plugins << Errapi::Plugins::Messages.new
-      config.register_validator :length, Errapi::Validators::Length
-      config.register_validator :presence, Errapi::Validators::Presence
+      config.register_validation :length, Errapi::Validations::Length
+      config.register_validation :presence, Errapi::Validations::Presence
       config.register_condition Errapi::Condition::SimpleCheck
       config.register_condition Errapi::Condition::ErrorCheck
+      config.register_location :dotted, Errapi::Locations::Dotted
+      config.register_location :json, Errapi::Locations::Json
     end
   end
 end

lib/errapi/configuration.rb

@@ -3,36 +3,62 @@ class Errapi::Configuration
 
   def initialize
     @plugins = []
-    @validators = {}
-    @conditions = {}
+    @validation_factories = {}
+    @condition_factories = {}
+    @location_factories = {}
+  end
+
+  def new_error options = {}
+    Errapi::ValidationError.new options
+  end
+
+  def build_error error, context
+    apply_plugins :build_error, error, context
   end
 
   def new_context
-    Errapi::ValidationContext.new plugins: @plugins
+    Errapi::ValidationContext.new config: self
+  end
+
+  def register_validation name, factory
+    @validation_factories[name] = factory
   end
 
-  def register_validator name, factory
-    @validators[name] = factory
+  def validation name, options = {}
+    raise ArgumentError, "No validation factory registered for name #{name.inspect}" unless @validation_factories.key? name
+    @validation_factories[name].new options
   end
 
-  def validator name, options = {}
-    raise ArgumentError, "No validator factory registered for name #{name.inspect}" unless @validators.key? name
-    @validators[name].new options
+  def register_location name, factory
+    @location_factories[name] = factory
+  end
+
+  def location name, initial_location = nil
+    raise ArgumentError, "No location factory registered for name #{name.inspect}" unless @location_factories.key? name
+    @location_factories[name].new initial_location
   end
 
   def register_condition factory
     factory.conditionals.each do |conditional|
       raise ArgumentError, "Conditional #{conditional} should start with 'if' or 'unless'." unless conditional.to_s.match /^(if|unless)/
-      @conditions[conditional] = factory
+      @condition_factories[conditional] = factory
     end
   end
 
   def extract_conditions! source, options = {}
     [].tap do |conditions|
-      @conditions.each_pair do |conditional,factory|
+      @condition_factories.each_pair do |conditional,factory|
         next unless source.key? conditional
         conditions << factory.new(conditional, source.delete(conditional), options)
       end
     end
   end
+
+  private
+
+  def apply_plugins operation, *args
+    @plugins.each do |plugin|
+      plugin.send operation, *args if plugin.respond_to? operation
+    end
+  end
 end

lib/errapi/errors.rb

@@ -1,12 +1,13 @@
 module Errapi
   class Error < StandardError; end
   class ValidationErrorInvalid < Error; end
+  class ValidationDefinitionInvalid < Error; end
 
   class ValidationFailed < Error
     attr_reader :context
 
     def initialize context
-      super "A validation error occurred."
+      super "#{context.errors.length} errors were found during validation."
       @context = context
     end
   end

lib/errapi/validators.rb → lib/errapi/locations.rb

@@ -1,4 +1,4 @@
-module Errapi::Validators
+module Errapi::Locations
 end
 
 Dir[File.join File.dirname(__FILE__), File.basename(__FILE__, '.*'), '*.rb'].each{ |lib| require lib }

lib/errapi/locations/dotted.rb

@@ -0,0 +1,29 @@
+module Errapi
+
+  class Locations::Dotted
+
+    def initialize location = nil
+      @location = location.to_s.sub /^\./, '' unless location.nil?
+    end
+
+    def relative parts
+      if @location.nil?
+        self.class.new parts
+      else
+        self.class.new "#{@location}.#{parts.to_s.sub(/^\./, '')}"
+      end
+    end
+
+    def error_options
+      @location.nil? ? {} : { location: @location, location_type: :dotted }
+    end
+
+    def serialize
+      @location.nil? ? nil : @location
+    end
+
+    def to_s
+      @location.to_s
+    end
+  end
+end

lib/errapi/locations/json.rb

@@ -0,0 +1,29 @@
+module Errapi
+
+  class Locations::Json
+
+    def initialize location = nil
+      @location = location.nil? ? '' : location.to_s.sub(/^\//, '').sub(/\/$/, '')
+    end
+
+    def relative parts
+      if @location.nil?
+        self.class.new parts
+      else
+        self.class.new "#{@location}/#{parts.to_s.sub(/^\./, '').sub(/\/$/, '')}"
+      end
+    end
+
+    def error_options
+      { location: @location, location_type: :json }
+    end
+
+    def serialize
+      @location
+    end
+
+    def to_s
+      @location
+    end
+  end
+end

lib/errapi/locations/none.rb

@@ -0,0 +1,28 @@
+require 'singleton'
+
+module Errapi
+
+  class Locations::None
+    include Singleton
+
+    def relative parts
+      self
+    end
+
+    def error_options
+      {}
+    end
+
+    def serialize
+      nil
+    end
+
+    def to_s
+      LOCATION_STRING
+    end
+
+    private
+
+    LOCATION_STRING = ''
+  end
+end

lib/errapi/model.rb

@@ -10,8 +10,8 @@ def validate *args
       context = args.shift
     end
 
-    validations = self.class.errapi name
-    validations.validate self, context, options
+    validator = self.class.errapi name
+    validator.validate self, context, options
   end
 
   def self.included mod
@@ -20,9 +20,10 @@ def self.included mod
 
   module ClassMethods
 
-    def errapi name = nil, &block
-      @errapi_validations ||= {}
-      @errapi_validations[name || :default] ||= Errapi::ObjectValidations.new(&block)
+    def errapi name = :default, &block
+      @errapi_validators ||= {}
+      @errapi_validators[name] = Errapi::ObjectValidator.new(&block) if block
+      @errapi_validators[name]
     end
   end
 end