App /health endpoint with info related to OS, memory, file system and GCv0.9.2

1 files changed, 54 insertions, 0 deletions

diff --git a/src/main/scala/com/drivergrp/core/stats.scala b/src/main/scala/com/drivergrp/core/stats.scala
index cd77f7a..963e4ea 100644
--- a/src/main/scala/com/drivergrp/core/stats.scala
+++ b/src/main/scala/com/drivergrp/core/stats.scala
@@ -1,5 +1,9 @@
 package com.drivergrp.core
 
+import java.io.File
+import java.lang.management.ManagementFactory
+import java.lang.reflect.Modifier
+
 import com.drivergrp.core.logging.Logger
 import com.drivergrp.core.time.{Time, TimeRange}
 
@@ -40,4 +44,54 @@ object stats {
       log.audit(s"${keys.mkString(".")}(${interval.start.millis}-${interval.end.millis})=$valueString")
     }
   }
+
+  final case class MemoryStats(free: Long, total: Long, max: Long)
+
+  final case class GarbageCollectorStats(totalGarbageCollections: Long, garbageCollectionTime: Long)
+
+  final case class FileRootSpace(path: String, totalSpace: Long, freeSpace: Long, usableSpace: Long)
+
+  object SystemStats {
+
+    def memoryUsage: MemoryStats = {
+      val runtime = Runtime.getRuntime
+      MemoryStats(runtime.freeMemory, runtime.totalMemory, runtime.maxMemory)
+    }
+
+    def availableProcessors: Int = {
+      Runtime.getRuntime.availableProcessors()
+    }
+
+    def garbageCollectorStats: GarbageCollectorStats = {
+      import scala.collection.JavaConverters._
+
+      val (totalGarbageCollections, garbageCollectionTime) =
+        ManagementFactory.getGarbageCollectorMXBeans.asScala.foldLeft(0L -> 0L) {
+          case ((total, collectionTime), gc) =>
+            (total + math.min(0L, gc.getCollectionCount)) -> (collectionTime + math.min(0L, gc.getCollectionTime))
+        }
+
+      GarbageCollectorStats(totalGarbageCollections, garbageCollectionTime)
+    }
+
+    def fileSystemSpace: Array[FileRootSpace] = {
+      File.listRoots() map { root =>
+        FileRootSpace(root.getAbsolutePath, root.getTotalSpace, root.getFreeSpace, root.getUsableSpace)
+      }
+    }
+
+    def operatingSystemStats: Map[String, String] = {
+      val operatingSystemMXBean = ManagementFactory.getOperatingSystemMXBean
+      operatingSystemMXBean.getClass.getDeclaredMethods
+        .map(method => { method.setAccessible(true); method })
+        .filter(method => method.getName.startsWith("get") && Modifier.isPublic(method.getModifiers))
+        .map { method =>
+          try {
+            method.getName -> String.valueOf(method.invoke(operatingSystemMXBean))
+          } catch {
+            case t: Throwable => method.getName -> t.getMessage
+        }
+      } toMap
+    }
+  }
 }