add support for the "patternProperties" attribute

lib/jsonschema.rb

@@ -106,6 +106,14 @@ def check_property value, schema, key, parent
               end
             elsif schema['properties']
               check_object(value, schema['properties'], schema['additionalProperties'])
+            elsif schema['patternProperties']
+              value.each { |k, val|
+                schema['patternProperties'].each { |pattern_string, pattern_schema|
+                  if k =~ Regexp.new(pattern_string)
+                    check_property(val, schema['patternProperties'][pattern_string], k, value)
+                  end
+                }
+              }
             elsif schema.include?('additionalProperties')
               additional = schema['additionalProperties']
               unless additional.kind_of?(TrueClass)

test/jsonschema_test.rb

@@ -892,6 +892,39 @@ def test_additionalProperties
     end
   end
 
+  def test_patternProperties
+    schema1 = {
+      "patternProperties" => {
+        "^i.*$" => {
+          "type" => "integer"
+        },
+        "^s.*$" => {
+          "type" => "string"
+        },
+        "^b.*$" => {
+          "type" => "boolean"
+        }
+      }
+    }
+    data1 = {
+      "iabc" => 123,
+      "s456" => "val",
+      "another" => { "hash" => 1234 }
+    }
+    assert_nothing_raised{
+      JSON::Schema.validate(data1, schema1)
+    }
+    data2 = {
+      "iabc" => 123,
+      "s456" => "val",
+      "another" => { "hash" => 1234 },
+      "b567" => "string_instead_of_boolean"
+    }
+    assert_raise(JSON::Schema::ValueError){
+      JSON::Schema.validate(data2, schema1)
+    }
+  end
+
   def test_disallow
     # multi phase
     schema = {"disallow"=>["null","integer","string"]}