Add --ignore-empty-record-stream flag

flow/record/tools/rdump.py

@@ -13,6 +13,7 @@
 
 import flow.record.adapter
 from flow.record import RecordWriter, iter_timestamped_records, record_stream
+from flow.record.exceptions import RecordAdapterNotFound
 from flow.record.selector import make_selector
 from flow.record.stream import RecordFieldRewriter
 from flow.record.utils import LOGGING_TRACE_LEVEL, catch_sigpipe
@@ -143,6 +144,11 @@ def main(argv: list[str] | None = None) -> int:
         action="store_true",
         help="Show count of processed records",
     )
+    output.add_argument(
+        "--ignore-empty-record-stream",
+        action="store_true",
+        help="Exit successfully if no records can be read",
+    )
 
     advanced = parser.add_argument_group("advanced")
     advanced.add_argument(
@@ -315,13 +321,17 @@ def main(argv: list[str] | None = None) -> int:
                     record_writer.write(rec)
 
     except Exception as e:
-        print_error(e)
+        if args.ignore_empty_record_stream and count == 0 and isinstance(e, RecordAdapterNotFound):
+            log.warning("No records were read from the input stream")
+            ret = 0
+        else:
+            print_error(e)
 
-        # Prevent throwing an exception twice when deconstructing the record writer.
-        if hasattr(record_writer, "exception") and record_writer.exception is e:
-            record_writer.exception = None
+            # Prevent throwing an exception twice when deconstructing the record writer.
+            if hasattr(record_writer, "exception") and record_writer.exception is e:
+                record_writer.exception = None
 
-        ret = 1
+            ret = 1
 
     finally:
         if record_writer:

tests/test_rdump.py

@@ -90,6 +90,28 @@ def test_rdump_pipe(tmp_path: Path) -> None:
     assert len(records) == 3
     assert {r.count for r in records} == {1, 3, 9}
 
+    # Test if rdump exits with exit code 1 when no records can be read from stdin
+    p1 = subprocess.Popen(["echo", ""], stdout=subprocess.PIPE)
+    p2 = subprocess.Popen(["rdump", "-"], stdin=p1.stdout, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    stdout, stderr = p2.communicate()
+
+    assert p2.returncode == 1
+    assert b"rdump encountered a fatal error: Could not find adapter for file-like object" in stderr
+
+    # Test if rdump exits with exit code 0 when no records can be read from stdin
+    # and --ignore-empty-record-stream is set
+    p1 = subprocess.Popen(["echo", ""], stdout=subprocess.PIPE)
+    p2 = subprocess.Popen(
+        ["rdump", "-v", "-", "--ignore-empty-record-stream"],
+        stdin=p1.stdout,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+    )
+    stdout, stderr = p2.communicate()
+
+    assert p2.returncode == 0
+    assert b"No records were read from the input stream" in stderr
+
 
 def test_rdump_format_template(tmp_path: Path) -> None:
     TestRecord = RecordDescriptor(