ruby-sdk/lib/mcp/server/transports/stdio_transport.rb

# frozen_string_literal: true

require_relative "../../transport"
require "json"

module MCP
  class Server
    module Transports
      class StdioTransport < Transport
        def initialize(server)
          @server = server
          @open = false
          $stdin.set_encoding("UTF-8")
          $stdout.set_encoding("UTF-8")
          super
        end

        def open
          @open = true
          while @open && (line = $stdin.gets)
            handle_json_request(line.strip)
          end
        end

        def close
          @open = false
        end

        def send_response(message)
          json_message = message.is_a?(String) ? message : JSON.generate(message)
          $stdout.puts(json_message)
          $stdout.flush
        end
      end
    end
  end
end