Update app.py

app.py

@@ -3,27 +3,18 @@ import httpx
 from fastapi import FastAPI, Request, HTTPException
 from fastmcp import FastMCP
 
-app = FastAPI()
-
+# Create the MCP server (FastMCP creates its own FastAPI app internally)
 mcp = FastMCP(name="SAP MCP Proxy", version="0.1")
 
 API_GATEWAY_KEY = os.getenv("API_GATEWAY_KEY")
 
-# Middleware applied on FastAPI app
-@app.middleware("http")
-async def check_api_key(request: Request, call_next):
-    if request.url.path in ["/", "/docs", "/redoc"]:
-        return await call_next(request)
-    token = request.headers.get("X-API-Key")
-    if token != API_GATEWAY_KEY:
-        raise HTTPException(status_code=401, detail="Invalid or missing API key")
-    return await call_next(request)
-
-@mcp.tool(description="Fetch 50 supplier invoices from SAP API")
+# Define the MCP tool
+@mcp.tool(description="Fetch 50 supplier invoices from SAP S/4HANA OData API")
 async def get_supplier_invoices():
     api_key = os.getenv("API_KEY")
     if not api_key:
-        return {"error": "API_KEY not configured"}
+        return {"error": "SAP API_KEY not configured"}
+    
     url = "https://sandbox.api.sap.com/s4hanacloud/sap/opu/odata/sap/API_SUPPLIERINVOICE_PROCESS_SRV/A_BR_SupplierInvoiceNFDocument?$top=50&$inlinecount=allpages"
     headers = {
         "APIKey": api_key,
@@ -36,13 +27,33 @@ async def get_supplier_invoices():
         else:
             return {"error": resp.status_code, "body": resp.text}
 
-# mount MCP routes on regular FastAPI app
-mcp.mount(app)
+# Create HTTP ASGI app from MCP server for mounting
+mcp_app = mcp.http_app(path='/mcp')
+
+# Create a new FastAPI app and combine routes
+app = FastAPI(
+    title="SAP MCP Proxy",
+    routes=[*mcp_app.routes],  # Include MCP routes
+    lifespan=mcp_app.lifespan  # Important: pass lifespan for MCP initialization
+)
+
+# Add custom middleware for authentication
+@app.middleware("http")
+async def check_api_key(request: Request, call_next):
+    if request.url.path in ["/", "/docs", "/redoc", "/routes"]:
+        return await call_next(request)
+    token = request.headers.get("X-API-Key")
+    if not token or token != API_GATEWAY_KEY:
+        raise HTTPException(status_code=401, detail="Invalid or missing API key")
+    response = await call_next(request)
+    return response
 
+# Health check endpoint
 @app.get("/")
 def root():
     return {"message": "SAP MCP Proxy is running"}
 
+# Debug endpoint to list routes
 @app.get("/routes")
 def get_routes():
     return [route.path for route in app.routes]