Reserve ports in blocks in order to avoid collisions

Fixes #21.
mesosphere · Sep 12, 2013 · 7490ed4 · 7490ed4
1 parent 068b90b
commit 7490ed4
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Showing 2 changed files with 98 additions and 4 deletions.
diff --git a/src/main/scala/mesosphere/mesos/TaskBuilder.scala b/src/main/scala/mesosphere/mesos/TaskBuilder.scala
@@ -125,6 +125,7 @@ object TaskBuilder {
   final val cpusResourceName = "cpus"
   final val memResourceName = "mem"
   final val portsResourceName = "ports"
+  final val portBlockSize = 5
 
   def scalarResource(name: String, value: Double) = {
     Resource.newBuilder
@@ -174,10 +175,17 @@ object TaskBuilder {
   }
 
   def getPort(resource: Resource): Option[Int] = {
-    if (resource.getRanges.getRangeCount > 0) {
-      Some(resource.getRanges.getRange(0).getBegin.toInt)
+    val ranges = resource.getRanges.getRangeList.asScala.map ( range => {
+      val portRangeBegin = range.getBegin.toInt + (range.getBegin.toInt % portBlockSize)
+      val blocksAvailable = (range.getEnd.toInt - portRangeBegin + 1) / portBlockSize
+      (portRangeBegin, blocksAvailable)
+    }).filter(range => (range._2 > 0))
+
+    if (ranges.size > 0) {
+      val range = util.Random.shuffle(ranges).head
+      Some((util.Random.nextInt(range._2) * 5) + range._1)
     } else {
       None
     }
   }
-}
+}
diff --git a/src/test/scala/mesosphere/mesos/TaskBuilderTest.scala b/src/test/scala/mesosphere/mesos/TaskBuilderTest.scala
@@ -134,4 +134,90 @@ class TaskBuilderTest  extends AssertionsForJUnit with MockitoSugar {
         .build())
       .build()
   }
-}
+
+  @Test
+  def testGetPortSingleRange() = {
+    val maxPort = 32000L
+    val minPort = 31000L
+
+    val range = Value.Range.newBuilder
+      .setBegin(minPort)
+      .setEnd(maxPort)
+      .build
+    val ranges = Ranges.newBuilder
+      .addRange(range)
+      .build
+    val portResource = Resource.newBuilder
+      .setName(TaskBuilder.portsResourceName)
+      .setType(Value.Type.RANGES)
+      .setRanges(ranges)
+      .build
+
+    val port = TaskBuilder.getPort(portResource)
+
+    assertTrue(port.get > minPort && port.get < maxPort)
+    assertEquals(port.get % TaskBuilder.portBlockSize,0)
+  }
+
+  @Test
+  def testGetPortMultipleRanges() = {
+    val maxPort1 = 31009L
+    val minPort1 = 31000L
+
+    val maxPort2 = 30003L
+    val minPort2 = 30000L
+
+    val range1 = Value.Range.newBuilder
+      .setBegin(minPort1)
+      .setEnd(maxPort1)
+      .build
+    val range2 = Value.Range.newBuilder
+      .setBegin(minPort2)
+      .setEnd(maxPort2)
+      .build
+    val ranges = Ranges.newBuilder
+      .addRange(range1)
+      .addRange(range2)
+      .build
+    val portResource = Resource.newBuilder
+      .setName(TaskBuilder.portsResourceName)
+      .setType(Value.Type.RANGES)
+      .setRanges(ranges)
+      .build
+
+    val port = TaskBuilder.getPort(portResource)
+
+    assertTrue(port.get == 31000 || port.get == 31005)
+  }
+
+  @Test
+  def testGetPortNotEnoughBlocksInRange() = {
+    val maxPort1 = 31003L
+    val minPort1 = 31000L
+
+    val maxPort2 = 30003L
+    val minPort2 = 30000L
+
+    val range1 = Value.Range.newBuilder
+      .setBegin(minPort1)
+      .setEnd(maxPort1)
+      .build
+    val range2 = Value.Range.newBuilder
+      .setBegin(minPort2)
+      .setEnd(maxPort2)
+      .build
+    val ranges = Ranges.newBuilder
+      .addRange(range1)
+      .addRange(range2)
+      .build
+    val portResource = Resource.newBuilder
+      .setName(TaskBuilder.portsResourceName)
+      .setType(Value.Type.RANGES)
+      .setRanges(ranges)
+      .build
+
+    val port = TaskBuilder.getPort(portResource)
+
+    assertTrue(port.isEmpty)
+  }
+}