Prometheus exporter: omit empty otel_scope_info and otel_target_info …

…metrics (#5887)
open-telemetry · Oct 11, 2023 · 3c52cdf · 3c52cdf
1 parent cc8774f
commit 3c52cdf
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Showing 3 changed files with 31 additions and 30 deletions.
diff --git a/exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/Serializer.java b/exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/Serializer.java
@@ -244,6 +244,10 @@ private static boolean isDeltaTemporality(MetricData metricData) {
   }
 
   private static void writeResource(Resource resource, Writer writer) throws IOException {
+    if (resource.getAttributes().isEmpty()) {
+      return;
+    }
+
     writer.write("# TYPE target info\n");
     writer.write("# HELP target Target metadata\n");
     writer.write("target_info{");
@@ -253,6 +257,10 @@ private static void writeResource(Resource resource, Writer writer) throws IOExc
 
   private static void writeScopeInfo(
       InstrumentationScopeInfo instrumentationScopeInfo, Writer writer) throws IOException {
+    if (instrumentationScopeInfo.getAttributes().isEmpty()) {
+      return;
+    }
+
     writer.write("# TYPE otel_scope_info info\n");
     writer.write("# HELP otel_scope_info Scope metadata\n");
     writer.write("otel_scope_info{");

diff --git a/...ometheus/src/test/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerTest.java b/...ometheus/src/test/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerTest.java
@@ -117,12 +117,6 @@ void fetchPrometheus(String endpoint) {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"grpc\",otel_scope_version=\"version\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"http\",otel_scope_version=\"version\"} 1\n"
                 + "# TYPE grpc_name_total counter\n"
                 + "# HELP grpc_name_total long_description\n"
                 + "grpc_name_total{otel_scope_name=\"grpc\",otel_scope_version=\"version\",kp=\"vp\"} 5.0 0\n"
@@ -152,12 +146,6 @@ void fetchOpenMetrics(String endpoint) {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"grpc\",otel_scope_version=\"version\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"http\",otel_scope_version=\"version\"} 1\n"
                 + "# TYPE grpc_name counter\n"
                 + "# HELP grpc_name long_description\n"
                 + "grpc_name_total{otel_scope_name=\"grpc\",otel_scope_version=\"version\",kp=\"vp\"} 5.0 0.000\n"
@@ -179,9 +167,6 @@ void fetchFiltered() {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"grpc\",otel_scope_version=\"version\"} 1\n"
                 + "# TYPE grpc_name_total counter\n"
                 + "# HELP grpc_name_total long_description\n"
                 + "grpc_name_total{otel_scope_name=\"grpc\",otel_scope_version=\"version\",kp=\"vp\"} 5.0 0\n");
@@ -206,12 +191,6 @@ void fetchPrometheusCompressed() throws IOException {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"grpc\",otel_scope_version=\"version\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"http\",otel_scope_version=\"version\"} 1\n"
                 + "# TYPE grpc_name_total counter\n"
                 + "# HELP grpc_name_total long_description\n"
                 + "grpc_name_total{otel_scope_name=\"grpc\",otel_scope_version=\"version\",kp=\"vp\"} 5.0 0\n"
@@ -287,12 +266,6 @@ void fetch_DuplicateMetrics() {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"scope1\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"scope2\"} 1\n"
                 + "# TYPE foo_unit_total counter\n"
                 + "# HELP foo_unit_total description1\n"
                 + "foo_unit_total{otel_scope_name=\"scope1\"} 1.0 0\n"

diff --git a/exporters/prometheus/src/test/java/io/opentelemetry/exporter/prometheus/SerializerTest.java b/exporters/prometheus/src/test/java/io/opentelemetry/exporter/prometheus/SerializerTest.java
@@ -241,16 +241,36 @@ void outOfOrderedAttributes() {
             "# TYPE target info\n"
                 + "# HELP target Target metadata\n"
                 + "target_info{kr=\"vr\"} 1\n"
-                + "# TYPE otel_scope_info info\n"
-                + "# HELP otel_scope_info Scope metadata\n"
-                + "otel_scope_info{otel_scope_name=\"scope\",otel_scope_version=\"1.0.0\"} 1\n"
                 + "# TYPE sum_seconds_total counter\n"
                 + "# HELP sum_seconds_total description\n"
                 + "sum_seconds_total{otel_scope_name=\"scope\",otel_scope_version=\"1.0.0\",b_key=\"val1\",a_key=\"val2\",b_key=\"val3\"} 5.0 1633950672000\n");
     logCapturer.assertContains(
         "Dropping out-of-order attribute a_key=val2, which occurred after b_key. This can occur when an alternative Attribute implementation is used.");
   }
 
+  @Test
+  void emptyResource() {
+    MetricData metricData =
+        ImmutableMetricData.createDoubleSum(
+            Resource.empty(),
+            InstrumentationScopeInfo.builder("scope").setVersion("1.0.0").build(),
+            "monotonic.cumulative.double.sum",
+            "description",
+            "s",
+            ImmutableSumData.create(
+                /* isMonotonic= */ true,
+                AggregationTemporality.CUMULATIVE,
+                Collections.singletonList(
+                    ImmutableDoublePointData.create(
+                        1633947011000000000L, 1633950672000000000L, Attributes.empty(), 5))));
+
+    assertThat(serialize004(metricData))
+        .isEqualTo(
+            "# TYPE monotonic_cumulative_double_sum_seconds_total counter\n"
+                + "# HELP monotonic_cumulative_double_sum_seconds_total description\n"
+                + "monotonic_cumulative_double_sum_seconds_total{otel_scope_name=\"scope\",otel_scope_version=\"1.0.0\"} 5.0 1633950672000\n");
+  }
+
   private static String serialize004(MetricData... metrics) {
     ByteArrayOutputStream bos = new ByteArrayOutputStream();
     try {