Accept logs without upstream timing

app/main.py

@@ -60,7 +60,9 @@ def percentile(values: list[float], p: float) -> float | None:
 def parse_line(line: str) -> dict[str, Any] | None:
     """Parse the configured, whitespace-delimited Nginx traffic format."""
     fields = line.strip().split()
-    if len(fields) < 8:
+    # A trailing empty $upstream_response_time disappears when splitting on
+    # whitespace, so seven fields is valid and means "no upstream timing".
+    if len(fields) < 7:
         return None
     try:
         timestamp = float(fields[0])
@@ -68,7 +70,7 @@ def parse_line(line: str) -> dict[str, Any] | None:
         request_length = int(fields[4])
         bytes_sent = int(fields[5])
         request_time = float(fields[6])
-        upstream_raw = "".join(fields[7:])
+        upstream_raw = "".join(fields[7:]) if len(fields) > 7 else "-"
         upstream_values = [float(value) for value in upstream_raw.split(",") if value not in ("", "-")]
         if not all(math.isfinite(value) and value >= 0 for value in
                    (timestamp, request_length, bytes_sent, request_time, *upstream_values)):

tests/test_main.py

@@ -10,6 +10,13 @@ def test_parse_line_and_multiple_upstreams():
     assert event["upstream_time"] == 0.15
 
 
+def test_parse_line_with_empty_trailing_upstream_time():
+    event = parse_line("1720000000.123 example.test GET 200 120 240 0.150")
+    assert event is not None
+    assert event["host"] == "example.test"
+    assert event["upstream_time"] is None
+
+
 def test_malformed_lines_are_ignored():
     assert parse_line("not enough fields") is None
     assert parse_line("1 host GET nope 1 2 0.1 -") is None