Implementing new Metric which displays the file count within the root…

… level of the JENKINS_HOME directory (#591)

Co-authored-by: Sailer, Manuel <[email protected]>

src/main/java/org/jenkinsci/plugins/prometheus/DiskUsageCollector.java

@@ -55,6 +55,7 @@ private static List<MetricFamilySamples> collectDiskUsage() throws IOException {
         final Set<FileStore> usedFileStores = new HashSet<>();
         List<MetricCollector<DiskItem, ? extends Collector>> diskItemCollectors = new ArrayList<>();
         diskItemCollectors.add(factory.createDiskItemCollector(CollectorType.DISK_USAGE_BYTES_GAUGE, new String[]{"file_store", "directory"}));
+        diskItemCollectors.add(factory.createDiskItemCollector(CollectorType.DISK_USAGE_FILE_COUNT_GAUGE, new String[]{"file_store", "directory"}));
 
         diskUsagePlugin.getDirectoriesUsages().forEach(i -> {
             final Optional<FileStore> fileStore = getFileStore(i.getPath());

src/main/java/org/jenkinsci/plugins/prometheus/collectors/CollectorType.java

@@ -30,6 +30,7 @@ public enum CollectorType {
     EXECUTORS_QUEUE_LENGTH_GAUGE("queue_length"),
 
     DISK_USAGE_BYTES_GAUGE("disk_usage_bytes"),
+    DISK_USAGE_FILE_COUNT_GAUGE("disk_usage_file_count"),
     FILE_STORE_AVAILABLE_GAUGE("file_store_available_bytes"),
     FILE_STORE_CAPACITY_GAUGE("file_store_capacity_bytes"),
     JOB_USAGE_BYTES_GAUGE("job_usage_bytes"),

src/main/java/org/jenkinsci/plugins/prometheus/collectors/disk/DiskCollectorFactory.java

@@ -23,6 +23,9 @@ public DiskCollectorFactory() {
         if (Objects.requireNonNull(type) == DISK_USAGE_BYTES_GAUGE) {
             return saveBuildCollector(new DiskUsageBytesGauge(labelNames, namespace, subsystem));
         }
+        if (Objects.requireNonNull(type) == DISK_USAGE_FILE_COUNT_GAUGE) {
+            return saveBuildCollector(new DiskUsageFileCountGauge(labelNames, namespace, subsystem));
+        }
         return new NoOpMetricCollector<>();
     }
 

src/main/java/org/jenkinsci/plugins/prometheus/collectors/disk/DiskUsageFileCountGauge.java

@@ -0,0 +1,37 @@
+package org.jenkinsci.plugins.prometheus.collectors.disk;
+
+import com.cloudbees.simplediskusage.DiskItem;
+import io.prometheus.client.Gauge;
+import io.prometheus.client.SimpleCollector;
+import org.jenkinsci.plugins.prometheus.collectors.BaseMetricCollector;
+import org.jenkinsci.plugins.prometheus.collectors.CollectorType;
+
+public class DiskUsageFileCountGauge extends BaseMetricCollector<DiskItem, Gauge> {
+
+    protected DiskUsageFileCountGauge(String[] labelNames, String namespace, String subsystem) {
+        super(labelNames, namespace, subsystem);
+    }
+
+    @Override
+    protected CollectorType getCollectorType() {
+        return CollectorType.DISK_USAGE_FILE_COUNT_GAUGE;
+    }
+
+    @Override
+    protected String getHelpText() {
+        return "Disk usage file count of the first level folder in JENKINS_HOME";
+    }
+
+    @Override
+    protected SimpleCollector.Builder<?, Gauge> getCollectorBuilder() {
+        return Gauge.build();
+    }
+
+    @Override
+    public void calculateMetric(DiskItem jenkinsObject, String[] labelValues) {
+        if (jenkinsObject == null) {
+            return;
+        }
+        this.collector.labels(labelValues).set(jenkinsObject.getCount());
+    }
+}

src/test/java/org/jenkinsci/plugins/prometheus/DiskUsageCollectorTest.java

@@ -92,14 +92,13 @@ public void shouldProduceMetrics() throws IOException {
             DiskUsageCollector underTest = new DiskUsageCollector();
             final List<MetricFamilySamples> samples = underTest.collect();
 
-            System.out.println("Size: " + samples.size());
-            for (MetricFamilySamples f :samples) {
-                System.out.println(f);
-            }
             assertThat(samples, containsInAnyOrder(
                 gauges("foo_bar_disk_usage_bytes", containsInAnyOrder(
                     sample(ImmutableMap.of("file_store", "the file store", "directory", "dir"), equalTo(11. * 1024))
                 )),
+                gauges("foo_bar_disk_usage_file_count", containsInAnyOrder(
+                    sample(ImmutableMap.of("file_store", "the file store", "directory", "dir"), equalTo(0.0))
+                )),
                 gauges("foo_bar_job_usage_bytes", containsInAnyOrder(
                     sample(ImmutableMap.of("file_store", "the file store", "jobName", "job name", "url", "/job"), equalTo(7. * 1024))
                 )),

src/test/java/org/jenkinsci/plugins/prometheus/collectors/disk/DiskUsageFileCountGaugeTest.java

@@ -0,0 +1,51 @@
+package org.jenkinsci.plugins.prometheus.collectors.disk;
+
+import com.cloudbees.simplediskusage.DiskItem;
+import io.prometheus.client.Collector;
+import org.jenkinsci.plugins.prometheus.collectors.testutils.CollectorTest;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import java.util.List;
+
+import static org.mockito.Mockito.when;
+
+@ExtendWith(MockitoExtension.class)
+class DiskUsageFileCountGaugeTest extends CollectorTest {
+
+    @Mock
+    DiskItem mock;
+
+    @Test
+    public void testCollectResult() {
+
+        when(mock.getCount()).thenReturn(10L);
+
+        DiskUsageFileCountGauge sut = new DiskUsageFileCountGauge(getLabelNames(), getNamespace(), getSubSystem());
+        sut.calculateMetric(mock, getLabelValues());
+
+        List<Collector.MetricFamilySamples> collect = sut.collect();
+
+        validateMetricFamilySampleListSize(collect, 1);
+
+        Collector.MetricFamilySamples samples = collect.get(0);
+
+        validateNames(samples, new String[]{"default_jenkins_disk_usage_file_count"});
+        validateMetricFamilySampleSize(samples, 1);
+        validateHelp(samples, "Disk usage file count of the first level folder in JENKINS_HOME");
+        validateValue(samples, 0, 10.0);
+    }
+
+    @Test
+    public void testDiskItemIsNull() {
+        DiskUsageFileCountGauge sut = new DiskUsageFileCountGauge(getLabelNames(), getNamespace(), getSubSystem());
+        sut.calculateMetric(null, getLabelValues());
+
+        List<Collector.MetricFamilySamples> collect = sut.collect();
+
+        validateMetricFamilySampleListSize(collect, 1);
+        validateMetricFamilySampleSize(collect.get(0), 0);
+    }
+}