prometheus · csmarchbanks · Oct 14, 2024 · Oct 11, 2024
diff --git a/prometheus_client/metrics_core.py b/prometheus_client/metrics_core.py
@@ -116,6 +116,7 @@ def __init__(self,
                 labels: Optional[Sequence[str]] = None,
                 created: Optional[float] = None,
                 unit: str = '',
+                 exemplar: Optional[Exemplar] = None,
                 ):
        # Glue code for pre-OpenMetrics metrics.
        if name.endswith('_total'):
@@ -127,13 +128,14 @@ def __init__(self,
            labels = []
        self._labelnames = tuple(labels)
        if value is not None:
-            self.add_metric([], value, created)
+            self.add_metric([], value, created, exemplar=exemplar)

    def add_metric(self,
                   labels: Sequence[str],
                   value: float,
                   created: Optional[float] = None,
                   timestamp: Optional[Union[Timestamp, float]] = None,
+                   exemplar: Optional[Exemplar] = None,
                   ) -> None:
        """Add a metric to the metric family.

@@ -142,7 +144,7 @@ def add_metric(self,
          value: The value of the metric
          created: Optional unix timestamp the child was created at.
        """
-        self.samples.append(Sample(self.name + '_total', dict(zip(self._labelnames, labels)), value, timestamp))
+        self.samples.append(Sample(self.name + '_total', dict(zip(self._labelnames, labels)), value, timestamp, exemplar))
        if created is not None:
            self.samples.append(Sample(self.name + '_created', dict(zip(self._labelnames, labels)), created, timestamp))


diff --git a/tests/test_core.py b/tests/test_core.py
@@ -724,6 +724,21 @@ def test_counter_labels(self):
        self.custom_collector(cmf)
        self.assertEqual(2, self.registry.get_sample_value('c_total', {'a': 'b', 'c_total': 'd'}))

+    def test_counter_exemplars_oneline(self):
+        cmf = CounterMetricFamily('c_total', 'help', value=23, exemplar={"bob": "osbourne"})
+        self.custom_collector(cmf)
+        sample = [c.samples for c in self.registry.collect()][0][0]
+        self.assertDictEqual({"bob": "osbourne"}, sample.exemplar)
+
+    def test_counter_exemplars_add(self):
+        cmf = CounterMetricFamily('c_total', 'help')
+        cmf.add_metric([], 12, exemplar={"bob": "osbourne"}, created=23)
+        self.custom_collector(cmf)
+        total_sample, created_sample = [c.samples for c in self.registry.collect()][0]
+        self.assertEqual("c_created", created_sample.name)
+        self.assertDictEqual({"bob": "osbourne"}, total_sample.exemplar)
+        self.assertIsNone(created_sample.exemplar)
+
    def test_gauge(self):
        self.custom_collector(GaugeMetricFamily('g', 'help', value=1))
        self.assertEqual(1, self.registry.get_sample_value('g', {}))