When a W3C baggage header contains sentry items whose values include = characters — which is legal per the spec, e.g. base64-encoded strings like v1.0==1 — Baggage.from_incoming_header silently discards those items.
The root cause is key, val = item.split("=") on line 722 of sentry_sdk/tracing_utils.py. Without a maxsplit argument, any value containing = causes split to return more than two parts, raising ValueError: too many values to unpack. This exception is swallowed by the surrounding capture_internal_exceptions() context manager, so the affected baggage item is silently dropped from sentry_items.
For example, the header sentry-release=v1.0==1,sentry-trace_id=abc123 produces {'trace_id': 'abc123'} instead of {'release': 'v1.0==1', 'trace_id': 'abc123'}.
To reproduce, run: python3 -c "from sentry_sdk.tracing_utils import Baggage; b = Baggage.from_incoming_header('sentry-release=v1.0==1,sentry-trace_id=abc123'); assert b.sentry_items == {'release': 'v1.0==1', 'trace_id': 'abc123'}, b.sentry_items"
When a W3C baggage header contains sentry items whose values include
=characters — which is legal per the spec, e.g. base64-encoded strings likev1.0==1—Baggage.from_incoming_headersilently discards those items.The root cause is
key, val = item.split("=")on line 722 ofsentry_sdk/tracing_utils.py. Without amaxsplitargument, any value containing=causessplitto return more than two parts, raisingValueError: too many values to unpack. This exception is swallowed by the surroundingcapture_internal_exceptions()context manager, so the affected baggage item is silently dropped fromsentry_items.For example, the header
sentry-release=v1.0==1,sentry-trace_id=abc123produces{'trace_id': 'abc123'}instead of{'release': 'v1.0==1', 'trace_id': 'abc123'}.To reproduce, run:
python3 -c "from sentry_sdk.tracing_utils import Baggage; b = Baggage.from_incoming_header('sentry-release=v1.0==1,sentry-trace_id=abc123'); assert b.sentry_items == {'release': 'v1.0==1', 'trace_id': 'abc123'}, b.sentry_items"