Add OpenAPI 3 parameter deserialization with style/explode support

Fixes: #446

Author: ydah

lib/committee/drivers/open_api_3/driver.rb

@@ -33,6 +33,11 @@ def default_validate_success_only
           false
         end
 
+        # Whether to deserialize parameters based on OpenAPI 3 style/explode settings
+        def default_deserialize_parameters
+          true
+        end
+
         def name
           :open_api_3
         end

lib/committee/errors.rb

@@ -33,4 +33,15 @@ class ReferenceNotFound < Error
 
   class OpenAPI3Unsupported < Error
   end
+
+  class ParameterDeserializationError < InvalidRequest
+    attr_reader :parameter_name, :style, :raw_value
+
+    def initialize(param_name, style, raw_value, message)
+      @parameter_name = param_name
+      @style = style
+      @raw_value = raw_value
+      super("Parameter '#{param_name}' (style: #{style}): #{message}")
+    end
+  end
 end

lib/committee/schema_validator/open_api_3.rb

@@ -93,6 +93,21 @@ def request_unpack(request)
 
         query_param = unpacker.unpack_query_params(request)
         query_param.merge!(request_param) if request.get? && validator_option.allow_get_body
+
+        if @operation_object && validator_option.deserialize_parameters
+          deserializer = ParameterDeserializer.new(@operation_object.request_operation)
+
+          query_param = deserializer.deserialize_query_params(query_param)
+
+          path_param = request.env[validator_option.path_hash_key]
+          path_param = deserializer.deserialize_path_params(path_param)
+          request.env[validator_option.path_hash_key] = path_param
+
+          headers = request.env[validator_option.headers_key]
+          headers = deserializer.deserialize_headers(headers)
+          request.env[validator_option.headers_key] = headers
+        end
+
         request.env[validator_option.query_hash_key] = query_param
       end
 
@@ -116,5 +131,6 @@ def copy_coerced_data_to_params(request)
 
 require_relative "open_api_3/router"
 require_relative "open_api_3/operation_wrapper"
+require_relative "open_api_3/parameter_deserializer"
 require_relative "open_api_3/request_validator"
 require_relative "open_api_3/response_validator"

lib/committee/schema_validator/open_api_3/operation_wrapper.rb

@@ -70,12 +70,11 @@ def request_content_types
           request_operation.operation_object&.request_body&.content&.keys || []
         end
 
-        private
-
+        # Expose request_operation for parameter deserialization
+        # @return [OpenAPIParser::RequestOperation]
         attr_reader :request_operation
 
-        # @!attribute [r] request_operation
-        #   @return [OpenAPIParser::RequestOperation]
+        private
 
         # @return [OpenAPIParser::SchemaValidator::Options]
         def build_openapi_parser_body_option(validator_option)