Add resources parameter to MCPServer (#2414)

Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>

src/mcp/server/mcpserver/resources/resource_manager.py

@@ -22,28 +22,26 @@ logger = get_logger(__name__)
 class ResourceManager:
     """Manages MCPServer resources."""
 
-    def __init__(self, warn_on_duplicate_resources: bool = True):
+    def __init__(self, warn_on_duplicate_resources: bool = True, *, resources: list[Resource] | None = None):
         self._resources: dict[str, Resource] = {}
         self._templates: dict[str, ResourceTemplate] = {}
         self.warn_on_duplicate_resources = warn_on_duplicate_resources
 
+        for resource in resources or ():
+            self.add_resource(resource)
+
     def add_resource(self, resource: Resource) -> Resource:
         """Add a resource to the manager.
 
         Args:
-            resource: A Resource instance to add
+            resource: A Resource instance to add.
 
         Returns:
-            The added resource. If a resource with the same URI already exists,
-            returns the existing resource.
+            The added resource. If a resource with the same URI already exists, returns the existing resource.
         """
         logger.debug(
             "Adding resource",
-            extra={
-                "uri": resource.uri,
-                "type": type(resource).__name__,
-                "resource_name": resource.name,
-            },
+            extra={"uri": resource.uri, "type": type(resource).__name__, "resource_name": resource.name},
         )
         existing = self._resources.get(str(resource.uri))
         if existing:

src/mcp/server/mcpserver/server.py

@@ -140,6 +140,7 @@ class MCPServer(Generic[LifespanResultT]):
         token_verifier: TokenVerifier | None = None,
         *,
         tools: list[Tool] | None = None,
+        resources: list[Resource] | None = None,
         debug: bool = False,
         log_level: Literal["DEBUG", "INFO", "WARNING", "ERROR", "CRITICAL"] = "INFO",
         warn_on_duplicate_resources: bool = True,
@@ -162,7 +163,9 @@ class MCPServer(Generic[LifespanResultT]):
         self.dependencies = self.settings.dependencies
 
         self._tool_manager = ToolManager(tools=tools, warn_on_duplicate_tools=self.settings.warn_on_duplicate_tools)
-        self._resource_manager = ResourceManager(warn_on_duplicate_resources=self.settings.warn_on_duplicate_resources)
+        self._resource_manager = ResourceManager(
+            resources=resources, warn_on_duplicate_resources=self.settings.warn_on_duplicate_resources
+        )
         self._prompt_manager = PromptManager(warn_on_duplicate_prompts=self.settings.warn_on_duplicate_prompts)
         self._lowlevel_server = Server(
             name=name or "mcp-server",

src/mcp/server/mcpserver/tools/tool_manager.py

@@ -18,18 +18,12 @@ logger = get_logger(__name__)
 class ToolManager:
     """Manages MCPServer tools."""
 
-    def __init__(
-        self,
-        warn_on_duplicate_tools: bool = True,
-        *,
-        tools: list[Tool] | None = None,
-    ):
+    def __init__(self, warn_on_duplicate_tools: bool = True, *, tools: list[Tool] | None = None):
         self._tools: dict[str, Tool] = {}
-        if tools is not None:
-            for tool in tools:
-                if warn_on_duplicate_tools and tool.name in self._tools:
-                    logger.warning(f"Tool already exists: {tool.name}")
-                self._tools[tool.name] = tool
+        for tool in tools or ():
+            if warn_on_duplicate_tools and tool.name in self._tools:
+                logger.warning(f"Tool already exists: {tool.name}")
+            self._tools[tool.name] = tool
 
         self.warn_on_duplicate_tools = warn_on_duplicate_tools