Add role-based filtering and imporve code

gateway/app/middleware/request_id.py

@@ -0,0 +1,83 @@
+"""
+Request ID Middleware for distributed tracing
+Generates and propagates unique request IDs across all services
+"""
+
+import uuid
+import structlog
+from fastapi import Request
+from starlette.middleware.base import BaseHTTPMiddleware
+from starlette.responses import Response
+
+logger = structlog.get_logger()
+
+
+class RequestIDMiddleware(BaseHTTPMiddleware):
+    """
+    Middleware to generate and propagate request IDs for distributed tracing.
+
+    Request IDs are:
+    - Generated if not provided by client
+    - Logged with every request
+    - Propagated to all downstream services
+    - Returned in response headers
+    """
+
+    def __init__(self, app):
+        super().__init__(app)
+
+    async def dispatch(self, request: Request, call_next) -> Response:
+        """Process request with request ID tracking"""
+
+        # Extract or generate request ID
+        request_id = request.headers.get("X-Request-ID")
+        if not request_id:
+            request_id = str(uuid.uuid4())
+
+        # Store in request state for access by routes
+        request.state.request_id = request_id
+
+        # Bind request ID to structured logger context
+        logger_ctx = logger.bind(request_id=request_id)
+
+        # Inject request ID header for downstream services
+        # This is done by modifying the headers that will be forwarded
+        request.headers.__dict__["_list"].append((
+            b"x-request-id", request_id.encode()
+        ))
+
+        # Log request start
+        logger_ctx.info(
+            "Request started",
+            method=request.method,
+            path=request.url.path,
+            client_ip=request.client.host if request.client else None
+        )
+
+        try:
+            # Process request
+            response = await call_next(request)
+
+            # Add request ID to response headers
+            response.headers["X-Request-ID"] = request_id
+
+            # Log request completion
+            logger_ctx.info(
+                "Request completed",
+                method=request.method,
+                path=request.url.path,
+                status_code=response.status_code
+            )
+
+            return response
+
+        except Exception as e:
+            # Log request failure
+            logger_ctx.error(
+                "Request failed",
+                method=request.method,
+                path=request.url.path,
+                error=str(e),
+                error_type=type(e).__name__
+            )
+            raise