Internal Release 0.5.2

Added
- Added stdio transport functionality.
Changed
- Added stdio details to the README.

test/model_context_protocol/transports/stdio_transport_test.rb

@@ -0,0 +1,125 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "model_context_protocol/transports/stdio"
+require "json"
+
+module ModelContextProtocol
+  module Transports
+    class StdioTransportTest < ActiveSupport::TestCase
+      include InstrumentationTestHelper
+
+      setup do
+        configuration = ModelContextProtocol::Configuration.new
+        configuration.instrumentation_callback = instrumentation_helper.callback
+        @server = Server.new(name: "test_server", configuration: configuration)
+        @transport = StdioTransport.new(@server)
+      end
+
+      test "initializes with server and closed state" do
+        server = @transport.instance_variable_get(:@server)
+        assert_equal @server.object_id, server.object_id
+        refute @transport.instance_variable_get(:@open)
+      end
+
+      test "processes JSON-RPC requests from stdin and sends responses to stdout" do
+        request = {
+          jsonrpc: "2.0",
+          method: "ping",
+          id: "123",
+        }
+        input = StringIO.new(JSON.generate(request) + "\n")
+        output = StringIO.new
+
+        original_stdin = $stdin
+        original_stdout = $stdout
+
+        begin
+          $stdin = input
+          $stdout = output
+
+          thread = Thread.new { @transport.open }
+          sleep(0.1)
+          @transport.close
+          thread.join
+
+          response = JSON.parse(output.string, symbolize_names: true)
+          assert_equal("2.0", response[:jsonrpc])
+          assert_equal("123", response[:id])
+          assert_equal({}, response[:result])
+          refute(@transport.instance_variable_get(:@open))
+        ensure
+          $stdin = original_stdin
+          $stdout = original_stdout
+        end
+      end
+
+      test "sends string responses to stdout" do
+        output = StringIO.new
+        original_stdout = $stdout
+
+        begin
+          $stdout = output
+          @transport.send_response("test response")
+          assert_equal("test response\n", output.string)
+        ensure
+          $stdout = original_stdout
+        end
+      end
+
+      test "sends JSON responses to stdout" do
+        output = StringIO.new
+        original_stdout = $stdout
+
+        begin
+          $stdout = output
+          response = { key: "value" }
+          @transport.send_response(response)
+          assert_equal(JSON.generate(response) + "\n", output.string)
+        ensure
+          $stdout = original_stdout
+        end
+      end
+
+      test "handles valid JSON-RPC requests" do
+        request = {
+          jsonrpc: "2.0",
+          method: "ping",
+          id: "123",
+        }
+        output = StringIO.new
+        original_stdout = $stdout
+
+        begin
+          $stdout = output
+          @transport.send(:handle_request, JSON.generate(request))
+          response = JSON.parse(output.string, symbolize_names: true)
+          assert_equal("2.0", response[:jsonrpc])
+          assert_nil(response[:id])
+          assert_nil(response[:result])
+        ensure
+          $stdout = original_stdout
+        end
+      end
+
+      test "handles invalid JSON requests" do
+        invalid_json = "invalid json"
+        output = StringIO.new
+        original_stdout = $stdout
+
+        begin
+          $stdout = output
+          @transport.send(:handle_request, invalid_json)
+          response = JSON.parse(output.string, symbolize_names: true)
+          assert_equal("2.0", response[:jsonrpc])
+          assert_nil(response[:id])
+          assert_equal(-32600, response[:error][:code])
+          assert_equal("Invalid Request", response[:error][:message])
+          assert_equal("Request must be an array or a hash", response[:error][:data])
+        ensure
+          $stdout = original_stdout
+        end
+      end
+    end
+  end
+end