add support for parsing values containing lists (#44)

* add support for parsing values containing lists

* add test for values containing lists

* fix test style

* black formatting fixes

---------

Co-authored-by: rivo nurges <[email protected]>

Author: rixxxx

mqtt_exporter/main.py

@@ -116,6 +116,12 @@ def _parse_metrics(data, topic, client_id, prefix=""):
     Note when `data` contains nested metrics this function will be called recursivley.
     """
     for metric, value in data.items():
+        # when value is a list recursivley call _parse_metrics to handle these messages
+        if isinstance(value, list):
+            LOG.debug("parsing list %s: %s", metric, value)
+            _parse_metrics(dict(enumerate(value)), topic, client_id, f"{prefix}{metric}_")
+            continue
+
         # when value is a dict recursivley call _parse_metrics to handle these messages
         if isinstance(value, dict):
             LOG.debug("parsing dict %s: %s", metric, value)

tests/functional/test_parse_metrics.py

@@ -36,3 +36,13 @@ def test_metrics_escaping():
     assert "mqtt_test_value_a" in main.prom_metrics
     assert "mqtt_test_value_b" in main.prom_metrics
     assert "mqtt_test_value_c" in main.prom_metrics
+
+
+def test_parse_metrics__value_is_list():
+    """Verify if list recursion works properly."""
+    main.prom_metrics = {}
+    parsed_topic = "test_topic"
+    parsed_payload = {"test_value": [1, 2]}
+    main._parse_metrics(parsed_payload, parsed_topic, "dummy_client_id")
+    assert "mqtt_test_value_0" in main.prom_metrics
+    assert "mqtt_test_value_1" in main.prom_metrics