Reduce conversion memory footprint

tests/test_parser.py

@@ -74,3 +74,19 @@ def test_parse_log_file_rebuilds_record_after_embedded_newlines():
     assert records[0]["msg"] == "hellobroken-fragmentworld"
     assert records[0]["action"] == "Alert"
     assert records[1]["msg"] == "next"
+
+
+def test_parse_log_file_does_not_require_full_stream_read():
+    class NoFullReadBytesIO(io.BytesIO):
+        def read(self, size=-1):
+            if size == -1:
+                raise AssertionError("full stream read should not be used")
+            return super().read(size)
+
+    stream = NoFullReadBytesIO(
+        b'v015xxxxdate=2024-02-15 time=09:10:11 policy="Strict Policy" msg="blocked request"\n'
+    )
+
+    records, _union_keys = parse_log_file(stream)
+
+    assert records[0]["policy"] == "Strict Policy"