Ensure metric attributes don't override Scope during collisions

Signed-off-by: Arthur Silva Sens <arthursens2005@gmail.com>

Author: ArthurSens

opentelemetry-prometheus/src/lib.rs

@@ -380,6 +380,10 @@ fn get_attrs(kvs: &mut dyn Iterator<Item = (&Key, &Value)>, extra: &[LabelPair])
     let mut keys_map = BTreeMap::<String, Vec<String>>::new();
     for (key, value) in kvs {
         let key = utils::sanitize_prom_kv(key.as_str());
+        if extra.iter().any(|label| label.name() == key) {
+            continue;
+        }
+
         keys_map
             .entry(key)
             .and_modify(|v| v.push(value.to_string()))

opentelemetry-prometheus/tests/integration_test.rs

@@ -54,6 +54,42 @@ fn scope_info_labels_are_added_to_metric_points() {
     assert!(!output.contains("reserved-schema-url"));
 }
 
+#[test]
+fn scope_info_labels_do_not_collide_with_metric_attributes() {
+    let registry = prometheus::Registry::new();
+    let exporter = ExporterBuilder::default()
+        .with_registry(registry.clone())
+        .build()
+        .unwrap();
+    let provider = SdkMeterProvider::builder().with_reader(exporter).build();
+
+    let scope = InstrumentationScope::builder("scope-test")
+        .with_version("v1.2.3")
+        .with_schema_url("https://opentelemetry.io/schemas/1.0.0")
+        .build();
+    let meter = provider.meter_with_scope(scope);
+
+    let counter = meter.u64_counter("scope.counter").build();
+    counter.add(
+        1,
+        &[
+            KeyValue::new("metric.attr", "metric-value"),
+            KeyValue::new("otel_scope_name", "metric-scope-name"),
+            KeyValue::new("otel_scope_version", "metric-scope-version"),
+            KeyValue::new("otel_scope_schema_url", "metric-scope-schema-url"),
+        ],
+    );
+
+    let output = gather_and_encode(registry);
+
+    assert!(output.contains(
+        r#"scope_counter_total{metric_attr="metric-value",otel_scope_name="scope-test",otel_scope_version="v1.2.3",otel_scope_schema_url="https://opentelemetry.io/schemas/1.0.0"} 1"#
+    ));
+    assert!(!output.contains("metric-scope-name"));
+    assert!(!output.contains("metric-scope-version"));
+    assert!(!output.contains("metric-scope-schema-url"));
+}
+
 #[test]
 fn scope_info_labels_can_be_disabled() {
     let registry = prometheus::Registry::new();