Initial commit

app/core/log_context.py

@@ -0,0 +1,30 @@
+"""
+Per-request logging context.
+
+Carries the request id (the same one `RequestIDMiddleware` puts on the
+`X-Request-ID` header) into every log record via a ContextVar + logging.Filter,
+so a whole request's log lines can be grepped by one id — essential when
+watching the live API.
+"""
+
+import contextvars
+import logging
+
+# Default "-" so non-request logs (startup, background agents) still format cleanly.
+_request_id: contextvars.ContextVar[str] = contextvars.ContextVar("request_id", default="-")
+
+
+def set_request_id(request_id: str) -> None:
+    _request_id.set(request_id or "-")
+
+
+def get_request_id() -> str:
+    return _request_id.get()
+
+
+class RequestIdFilter(logging.Filter):
+    """Injects `request_id` onto every LogRecord so the format string can use it."""
+
+    def filter(self, record: logging.LogRecord) -> bool:
+        record.request_id = _request_id.get()
+        return True