From 846c3da4ab2e94c17c39e636cb2ba10f174ec3e2 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Thu, 19 Dec 2013 13:21:41 -0800
Subject: [PATCH] Empty task intervals, and empty lock intervals, aren't
 useful.

So prevent them from being created, through checks in AbstractFixedIntervalTask
and TaskLockbox.tryLock.
---
 .../indexing/common/task/AbstractFixedIntervalTask.java    | 4 +++-
 .../main/java/io/druid/indexing/overlord/TaskLockbox.java  | 7 +++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/indexing-service/src/main/java/io/druid/indexing/common/task/AbstractFixedIntervalTask.java b/indexing-service/src/main/java/io/druid/indexing/common/task/AbstractFixedIntervalTask.java
index d1d494f5c83..2d6687ed920 100644
--- a/indexing-service/src/main/java/io/druid/indexing/common/task/AbstractFixedIntervalTask.java
+++ b/indexing-service/src/main/java/io/druid/indexing/common/task/AbstractFixedIntervalTask.java
@@ -21,6 +21,7 @@ package io.druid.indexing.common.task;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.base.Preconditions;
 import io.druid.indexing.common.actions.LockTryAcquireAction;
 import io.druid.indexing.common.actions.TaskActionClient;
 import org.joda.time.Interval;
@@ -58,7 +59,8 @@ public abstract class AbstractFixedIntervalTask extends AbstractTask
   )
   {
     super(id, groupId, taskResource, dataSource);
-    this.interval = interval;
+    this.interval = Preconditions.checkNotNull(interval, "interval");
+    Preconditions.checkArgument(interval.toDurationMillis() > 0, "interval empty");
   }
 
   @Override
diff --git a/indexing-service/src/main/java/io/druid/indexing/overlord/TaskLockbox.java b/indexing-service/src/main/java/io/druid/indexing/overlord/TaskLockbox.java
index d486f37c0fc..7b3ffb09087 100644
--- a/indexing-service/src/main/java/io/druid/indexing/overlord/TaskLockbox.java
+++ b/indexing-service/src/main/java/io/druid/indexing/overlord/TaskLockbox.java
@@ -19,6 +19,7 @@
 
 package io.druid.indexing.overlord;
 
+import com.google.api.client.repackaged.com.google.common.base.Preconditions;
 import com.google.common.base.Function;
 import com.google.common.base.Objects;
 import com.google.common.base.Optional;
@@ -109,6 +110,11 @@ public class TaskLockbox
       for (final Pair<Task, TaskLock> taskAndLock : byVersionOrdering.sortedCopy(storedLocks)) {
         final Task task = taskAndLock.lhs;
         final TaskLock savedTaskLock = taskAndLock.rhs;
+        if (savedTaskLock.getInterval().toDurationMillis() <= 0) {
+          // "Impossible", but you never know what crazy stuff can be restored from storage.
+          log.warn("WTF?! Got lock with empty interval for task: %s", task.getId());
+          continue;
+        }
         uniqueTaskIds.add(task.getId());
         final Optional<TaskLock> acquiredTaskLock = tryLock(
             task,
@@ -205,6 +211,7 @@ public class TaskLockbox
     giant.lock();
 
     try {
+      Preconditions.checkArgument(interval.toDurationMillis() > 0, "interval empty");
       final String dataSource = task.getDataSource();
       final List<TaskLockPosse> foundPosses = findLockPossesForInterval(dataSource, interval);
       final TaskLockPosse posseToUse;