prevent deadlock

Author: pmeier

CHANGELOG.md

@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+### Fixed
+
+- `opentelemetry-instrumentation-richconsole`: Prevent deadlock when parent span is not part of the batch
+
 ## Version 1.38.0/0.59b0 (2025-10-16)
 
 ### Fixed

exporter/opentelemetry-exporter-richconsole/src/opentelemetry/exporter/richconsole/__init__.py

@@ -173,14 +173,15 @@ def spans_to_tree(spans: typing.Sequence[ReadableSpan]) -> Dict[str, Tree]:
         trees = {}
         parents = {}
         spans = list(spans)
+        span_ids = {s.context.span_id for s in spans}
         while spans:
             for span in spans:
-                if not span.parent:
+                if not span.parent or span.parent.span_id not in span_ids:
                     trace_id = opentelemetry.trace.format_trace_id(
                         span.context.trace_id
                     )
-                    trees[trace_id] = Tree(label=f"Trace {trace_id}")
-                    child = trees[trace_id].add(
+                    tree = trees.setdefault(trace_id, Tree(label=f"Trace {trace_id}"))
+                    child = tree.add(
                         label=Text.from_markup(
                             f"[blue][{_ns_to_time(span.start_time)}][/blue] [bold]{span.name}[/bold], span {opentelemetry.trace.format_span_id(span.context.span_id)}"
                         )

exporter/opentelemetry-exporter-richconsole/tests/test_rich_exporter.py

@@ -96,3 +96,13 @@ def test_multiple_traces(tracer_provider):
         parent_2.name in child.label
         for child in trees[traceid_1].children[0].children
     )
+
+def test_no_deadlock(tracer_provider):
+    # non-regression test for https://github.com/open-telemetry/opentelemetry-python-contrib/issues/3254
+
+    tracer = tracer_provider.get_tracer(__name__)
+    with tracer.start_as_current_span("parent"):
+        with tracer.start_as_current_span("child") as child:
+            pass
+
+    RichConsoleSpanExporter.spans_to_tree((child,))