Merge pull request #225 from sjrct/add-client-resource-templates

Add resource_templates to MCP::Client

README.md

@@ -954,6 +954,7 @@ This class supports:
 - Tool listing via the `tools/list` method (`MCP::Client#tools`)
 - Tool invocation via the `tools/call` method (`MCP::Client#call_tools`)
 - Resource listing via the `resources/list` method (`MCP::Client#resources`)
+- Resource template listing via the `resources/templates/list` method (`MCP::Client#resource_templates`)
 - Resource reading via the `resources/read` method (`MCP::Client#read_resources`)
 - Prompt listing via the `prompts/list` method (`MCP::Client#prompts`)
 - Prompt retrieval via the `prompts/get` method (`MCP::Client#get_prompt`)

lib/mcp/client.rb

@@ -58,6 +58,20 @@ module MCP
       response.dig("result", "resources") || []
     end
 
+    # Returns the list of resource templates available from the server.
+    # Each call will make a new request – the result is not cached.
+    #
+    # @return [Array<Hash>] An array of available resource templates.
+    def resource_templates
+      response = transport.send_request(request: {
+        jsonrpc: JsonRpcHandler::Version::V2_0,
+        id: request_id,
+        method: "resources/templates/list",
+      })
+
+      response.dig("result", "resourceTemplates") || []
+    end
+
     # Returns the list of prompts available from the server.
     # Each call will make a new request – the result is not cached.
     #

test/mcp/client_test.rb

@@ -145,6 +145,43 @@ module MCP
       assert_empty(contents)
     end
 
+    def test_resource_templates_sends_request_to_transport_and_returns_resource_templates_array
+      transport = mock
+      mock_response = {
+        "result" => {
+          "resourceTemplates" => [
+            { "name" => "template1", "uriTemplate" => "file:///path/{filename}", "description" => "First template" },
+            { "name" => "template2", "uriTemplate" => "http://example.com/{id}", "description" => "Second template" },
+          ],
+        },
+      }
+
+      transport.expects(:send_request).with do |args|
+        args.dig(:request, :method) == "resources/templates/list" && args.dig(:request, :jsonrpc) == "2.0"
+      end.returns(mock_response).once
+
+      client = Client.new(transport: transport)
+      resource_templates = client.resource_templates
+
+      assert_equal(2, resource_templates.size)
+      assert_equal("template1", resource_templates.first["name"])
+      assert_equal("file:///path/{filename}", resource_templates.first["uriTemplate"])
+      assert_equal("template2", resource_templates.last["name"])
+      assert_equal("http://example.com/{id}", resource_templates.last["uriTemplate"])
+    end
+
+    def test_resource_templates_returns_empty_array_when_no_resource_templates
+      transport = mock
+      mock_response = { "result" => { "resourceTemplates" => [] } }
+
+      transport.expects(:send_request).returns(mock_response).once
+
+      client = Client.new(transport: transport)
+      resource_templates = client.resource_templates
+
+      assert_empty(resource_templates)
+    end
+
     def test_prompts_sends_request_to_transport_and_returns_prompts_array
       transport = mock
       mock_response = {