Merge pull request #11 from jlowin/list-templates

Prepare to list templates

src/fastmcp/resources/manager.py

@@ -62,6 +62,11 @@ def list_resources(self) -> list[Resource]:
         logger.debug("Listing resources", extra={"count": len(self._resources)})
         return list(self._resources.values())
 
+    def list_templates(self) -> list[ResourceTemplate]:
+        """List all registered templates."""
+        logger.debug("Listing templates", extra={"count": len(self._templates)})
+        return list(self._templates.values())
+
     def add_resource(self, resource: Resource) -> Resource:
         """Add a resource to the manager.
 

src/fastmcp/server.py

@@ -13,7 +13,8 @@
 from mcp.server.sse import SseServerTransport
 from mcp.types import (
     Resource as MCPResource,
-    Tool,
+    Tool as MCPTool,
+    ResourceTemplate as MCPResourceTemplate,
     TextContent,
     ImageContent,
 )
@@ -95,12 +96,14 @@ def _setup_handlers(self) -> None:
         self._mcp_server.call_tool()(self.call_tool)
         self._mcp_server.list_resources()(self.list_resources)
         self._mcp_server.read_resource()(self.read_resource)
+        # TODO: This has not been added to MCP yet, see https://github.com/jlowin/fastmcp/issues/10
+        # self._mcp_server.list_resource_templates()(self.list_resource_templates)
 
-    async def list_tools(self) -> list[Tool]:
+    async def list_tools(self) -> list[MCPTool]:
         """List all available tools."""
         tools = self._tool_manager.list_tools()
         return [
-            Tool(
+            MCPTool(
                 name=info.name,
                 description=info.description,
                 inputSchema=info.parameters,
@@ -139,6 +142,17 @@ async def list_resources(self) -> list[MCPResource]:
             for resource in resources
         ]
 
+    async def list_resource_templates(self) -> list[MCPResourceTemplate]:
+        templates = self._resource_manager.list_templates()
+        return [
+            MCPResourceTemplate(
+                uriTemplate=template.uri_template,
+                name=template.name,
+                description=template.description,
+            )
+            for template in templates
+        ]
+
     async def read_resource(self, uri: _BaseUrl) -> Union[str, bytes]:
         """Read a resource by URI."""
         resource = await self._resource_manager.get_resource(uri)

tests/test_server.py

@@ -265,8 +265,11 @@ async def test_file_resource_binary(self, tmp_path: Path):
                 == base64.b64encode(b"Binary file data").decode()
             )
 
+
+class TestServerResourceTemplates:
     async def test_resource_with_params(self):
-        """Test that a resource with function parameters is automatically a template"""
+        """Test that a resource with function parameters raises an error if the URI
+        parameters don't match"""
         mcp = FastMCP()
 
         with pytest.raises(ValueError, match="Mismatch between URI parameters"):
@@ -285,6 +288,14 @@ async def test_resource_with_uri_params(self):
             def get_data() -> str:
                 return "Data"
 
+    async def test_resource_with_untyped_params(self):
+        """Test that a resource with untyped parameters raises an error"""
+        mcp = FastMCP()
+
+        @mcp.resource("resource://{param}")
+        def get_data(param) -> str:
+            return "Data"
+
     async def test_resource_matching_params(self):
         """Test that a resource with matching URI and function parameters works"""
         mcp = FastMCP()
@@ -319,7 +330,16 @@ def get_data(org: str, repo: str) -> str:
             result = await client.read_resource("resource://cursor/fastmcp/data")
             assert result.contents[0].text == "Data for cursor/fastmcp"
 
-    async def test_resource_no_params(self):
+    async def test_resource_multiple_mismatched_params(self):
+        """Test that mismatched parameters raise an error"""
+        mcp = FastMCP()
+
+        with pytest.raises(ValueError, match="Mismatch between URI parameters"):
+
+            @mcp.resource("resource://{org}/{repo}/data")
+            def get_data(org: str, repo_2: str) -> str:
+                return f"Data for {org}"
+
         """Test that a resource with no parameters works as a regular resource"""
         mcp = FastMCP()
 
@@ -341,7 +361,7 @@ def get_data(name: str) -> str:
 
         # Should be registered as a template
         assert len(mcp._resource_manager._templates) == 1
-        assert len(mcp._resource_manager.list_resources()) == 0
+        assert len(await mcp.list_resources()) == 0
 
         # When accessed, should create a concrete resource
         resource = await mcp._resource_manager.get_resource("resource://test/data")