Support _created time series suppression

README.md

@@ -74,6 +74,13 @@ There are canonical examples defined in the class definition Javadoc of the clie
 Documentation can be found at the [Java Client
 Github Project Page](http://prometheus.github.io/client_java).
 
+### Disabling `_created` metrics
+
+By default, counters, histograms, and summaries export an additional series
+suffixed with `_created` and a value of the unix timestamp for when the metric
+was created. If this information is not helpful, it can be disabled by setting
+the environment variable `PROMETHEUS_DISABLE_CREATED_SERIES=true`.
+
 ## Instrumenting
 
 Four types of metrics are offered: Counter, Gauge, Summary and Histogram.

simpleclient/src/main/java/io/prometheus/client/Collector.java

@@ -3,8 +3,7 @@
 
 import io.prometheus.client.exemplars.Exemplar;
 
-import java.util.ArrayList;
-import java.util.List;
+import java.util.*;
 import java.util.regex.Pattern;
 
 /**

simpleclient/src/main/java/io/prometheus/client/Counter.java

@@ -355,7 +355,9 @@ public List<MetricFamilySamples> collect() {
     List<MetricFamilySamples.Sample> samples = new ArrayList<MetricFamilySamples.Sample>(children.size());
     for(Map.Entry<List<String>, Child> c: children.entrySet()) {
       samples.add(new MetricFamilySamples.Sample(fullname + "_total", labelNames, c.getKey(), c.getValue().get(), c.getValue().getExemplar()));
-      samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), c.getValue().created() / 1000.0));
+      if (Environment.includeCreatedSeries()) {
+        samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), c.getValue().created() / 1000.0));
+      }
     }
     return familySamplesList(Type.COUNTER, samples);
   }

simpleclient/src/main/java/io/prometheus/client/Environment.java

@@ -0,0 +1,23 @@
+package io.prometheus.client;
+
+import java.util.Arrays;
+import java.util.List;
+
+class Environment {
+
+    private static final String DISABLE_CREATED_SERIES = "PROMETHEUS_DISABLE_CREATED_SERIES";
+    private static final List<String> DISABLE_CREATED_SERIES_TRUE = Arrays.asList("true", "1", "t");
+    private static final boolean includeCreatedSeries = !isTrue(DISABLE_CREATED_SERIES);
+
+    static boolean includeCreatedSeries() {
+        return includeCreatedSeries;
+    }
+
+    private static boolean isTrue(String envVarName) {
+        String stringValue = System.getenv(envVarName);
+        if (stringValue != null) {
+            return DISABLE_CREATED_SERIES_TRUE.contains(stringValue.toLowerCase());
+        }
+        return false;
+    }
+}

simpleclient/src/main/java/io/prometheus/client/Histogram.java

@@ -574,7 +574,9 @@ public List<MetricFamilySamples> collect() {
       }
       samples.add(new MetricFamilySamples.Sample(fullname + "_count", labelNames, c.getKey(), v.buckets[buckets.length-1]));
       samples.add(new MetricFamilySamples.Sample(fullname + "_sum", labelNames, c.getKey(), v.sum));
-      samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), v.created / 1000.0));
+      if (Environment.includeCreatedSeries()) {
+        samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), v.created / 1000.0));
+      }
     }
 
     return familySamplesList(Type.HISTOGRAM, samples);

simpleclient/src/main/java/io/prometheus/client/Summary.java

@@ -404,7 +404,9 @@ public List<MetricFamilySamples> collect() {
       }
       samples.add(new MetricFamilySamples.Sample(fullname + "_count", labelNames, c.getKey(), v.count));
       samples.add(new MetricFamilySamples.Sample(fullname + "_sum", labelNames, c.getKey(), v.sum));
-      samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), v.created / 1000.0));
+      if (Environment.includeCreatedSeries()) {
+        samples.add(new MetricFamilySamples.Sample(fullname + "_created", labelNames, c.getKey(), v.created / 1000.0));
+      }
     }
 
     return familySamplesList(Type.SUMMARY, samples);

simpleclient/src/test/java/io/prometheus/client/HistogramTest.java

@@ -299,7 +299,7 @@ private void assertExemplar(Histogram histogram, double value, String... labels)
       }
       if (lowerBound < value && value <= upperBound) {
         Assert.assertNotNull("No exemplar found in bucket [" + lowerBound + ", " + upperBound + "]", bucket.exemplar);
-        Assert.assertEquals(value, bucket.exemplar.getValue(), 0.001);
+        Assert.assertEquals(value, bucket.exemplar.getValue(), 0.01);
         Assert.assertEquals(labels.length/2, bucket.exemplar.getNumberOfLabels());
         for (int i=0; i<labels.length; i+=2) {
           Assert.assertEquals(labels[i], bucket.exemplar.getLabelName(i/2));
@@ -327,7 +327,7 @@ private void assertNoExemplar(Histogram histogram, double value) {
       }
       if (lowerBound < value && value <= upperBound) {
         if (bucket.exemplar != null) {
-          Assert.assertNotEquals("expecting no exemplar with value " + value, value, bucket.exemplar.getValue(), 0.001);
+          Assert.assertNotEquals("expecting no exemplar with value " + value, value, bucket.exemplar.getValue(), 0.0001);
         }
       }
     }