Add basic HTTP client support with pluggable transports

test/mcp/client_test.rb

@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "securerandom"
+
+module MCP
+  class ClientTest < Minitest::Test
+    def test_tools_sends_request_to_transport_and_returns_tools_array
+      transport = mock
+      mock_response = {
+        "result" => {
+          "tools" => [
+            { "name" => "tool1", "description" => "tool1", "inputSchema" => {} },
+            { "name" => "tool2", "description" => "tool2", "inputSchema" => {} },
+          ],
+        },
+      }
+
+      # Only checking for the essential parts of the request
+      transport.expects(:send_request).with do |args|
+        args in { request: { method: "tools/list", jsonrpc: "2.0" } }
+      end.returns(mock_response).once
+
+      client = Client.new(transport: transport)
+      tools = client.tools
+
+      assert_equal(2, tools.size)
+      assert_equal("tool1", tools.first.name)
+      assert_equal("tool2", tools.last.name)
+    end
+
+    def test_call_tool_sends_request_to_transport_and_returns_content
+      transport = mock
+      tool = MCP::Client::Tool.new(name: "tool1", description: "tool1", input_schema: {})
+      arguments = { foo: "bar" }
+      mock_response = {
+        "result" => { "content" => "result" },
+      }
+
+      # Only checking for the essential parts of the request
+      transport.expects(:send_request).with do |args|
+        args in {
+          request: {
+            method: "tools/call",
+            jsonrpc: "2.0",
+            params: {
+              name: "tool1",
+              arguments: arguments,
+            },
+          },
+        }
+      end.returns(mock_response).once
+
+      client = Client.new(transport: transport)
+      result = client.call_tool(tool: tool, arguments: arguments)
+
+      assert_equal("result", result)
+    end
+  end
+end