fix: wasm with starlette issue

marimo/_mcp/server/lifespan.py

@@ -1,17 +1,19 @@
 # Copyright 2025 Marimo. All rights reserved.
 import contextlib
 from collections.abc import AsyncIterator
-
-from starlette.applications import Starlette
+from typing import TYPE_CHECKING
 
 from marimo._loggers import marimo_logger
 from marimo._mcp.server.main import setup_mcp_server
 
 LOGGER = marimo_logger()
 
+if TYPE_CHECKING:
+    from starlette.applications import Starlette
+
 
 @contextlib.asynccontextmanager
-async def mcp_server_lifespan(app: Starlette) -> AsyncIterator[None]:
+async def mcp_server_lifespan(app: "Starlette") -> AsyncIterator[None]:
     """Lifespan for MCP server functionality (exposing marimo as MCP server)."""
 
     try:

marimo/_mcp/server/main.py

@@ -9,7 +9,6 @@
 from typing import TYPE_CHECKING
 
 from mcp.server.fastmcp import FastMCP
-from starlette.routing import Mount
 
 from marimo._ai._tools.base import ToolContext
 from marimo._ai._tools.tools_registry import SUPPORTED_BACKEND_AND_MCP_TOOLS
@@ -34,6 +33,7 @@ def setup_mcp_server(app: "Starlette") -> "StreamableHTTPSessionManager":
     Returns:
         StreamableHTTPSessionManager: MCP session manager
     """
+    from starlette.routing import Mount
 
     mcp = FastMCP(
         "marimo-mcp-server",

marimo/_plugins/stateless/mpl/_mpl.py

@@ -17,8 +17,6 @@
 from pathlib import Path
 from typing import TYPE_CHECKING, Any, Optional, Union
 
-from starlette.responses import HTMLResponse, Response
-
 from marimo import _loggers
 from marimo._output.builder import h
 from marimo._output.formatting import as_html
@@ -42,6 +40,7 @@
     from matplotlib.figure import Figure, SubFigure
     from starlette.applications import Starlette
     from starlette.requests import Request
+    from starlette.responses import HTMLResponse, Response
     from starlette.websockets import WebSocket
 
 
@@ -222,39 +221,38 @@ def _template(fig_id: str, port: int) -> str:
     }
 
 
-async def mpl_js(request: Request) -> Response:
-    from matplotlib.backends.backend_webagg_core import (
-        FigureManagerWebAgg,
-    )
-
-    del request
-    return Response(
-        content=patch_javascript(FigureManagerWebAgg.get_javascript()),  # type: ignore[no-untyped-call]
-        media_type="application/javascript",
-    )
-
-
-async def mpl_custom_css(request: Request) -> Response:
-    del request
-    return Response(
-        content=css_content,
-        media_type="text/css",
-    )
-
-
 def create_application() -> Starlette:
     import matplotlib as mpl
     from matplotlib.backends.backend_webagg_core import (
         FigureManagerWebAgg,
     )
     from starlette.applications import Starlette
+    from starlette.responses import HTMLResponse, Response
     from starlette.routing import Mount, Route, WebSocketRoute
     from starlette.staticfiles import StaticFiles
     from starlette.websockets import (
         WebSocketDisconnect,
         WebSocketState,
     )
 
+    async def mpl_js(request: Request) -> Response:
+        from matplotlib.backends.backend_webagg_core import (
+            FigureManagerWebAgg,
+        )
+
+        del request
+        return Response(
+            content=patch_javascript(FigureManagerWebAgg.get_javascript()),  # type: ignore[no-untyped-call]
+            media_type="application/javascript",
+        )
+
+    async def mpl_custom_css(request: Request) -> Response:
+        del request
+        return Response(
+            content=css_content,
+            media_type="text/css",
+        )
+
     async def main_page(request: Request) -> HTMLResponse:
         figure_id = request.query_params.get("figure")
         assert figure_id is not None