From 0ef6c44c5b771f8bf8d0a73b7e2b3331dfdf19e4 Mon Sep 17 00:00:00 2001
From: Nathaniel Cook <nathaniel@influxdb.com>
Date: Mon, 18 Jul 2016 09:40:55 -0600
Subject: [PATCH] fix panic in replay (#720)

---
 CHANGELOG.md | 3 ++-
 replay.go    | 9 ++++++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d46e67baf..afdb010a8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,8 +8,9 @@
 
 ### Bugfixes
 
-- [#710](https://github.com/influxdata/kapacitor/pull/662): Fix infinite loop when parsing unterminated regex in TICKscript.
+- [#710](https://github.com/influxdata/kapacitor/pull/710): Fix infinite loop when parsing unterminated regex in TICKscript.
 - [#711](https://github.com/influxdata/kapacitor/issue/711): Fix where database name with quotes breaks subscription startup logic.
+- [#719](https://github.com/influxdata/kapacitor/pull/719): Fix panic on replay.
 
 ## v1.0.0-beta3 [2016-07-09]
 
diff --git a/replay.go b/replay.go
index 7c8700685..66a2b9c7f 100644
--- a/replay.go
+++ b/replay.go
@@ -173,11 +173,17 @@ func replayBatchFromChan(clck clock.Clock, batches <-chan models.Batch, collecto
 	defer collector.Close()
 
 	// Find relative times
-	start := time.Time{}
+	var start, tmax time.Time
 	var diff time.Duration
 	zero := clck.Zero()
 
 	for b := range batches {
+		if len(b.Points) == 0 {
+			// Emit empty batch
+			b.TMax = tmax
+			collector.CollectBatch(b)
+			continue
+		}
 		if start.IsZero() {
 			start = b.Points[0].Time
 			diff = zero.Sub(start)
@@ -193,6 +199,7 @@ func replayBatchFromChan(clck clock.Clock, batches <-chan models.Batch, collecto
 		}
 		clck.Until(lastTime)
 		b.TMax = b.Points[len(b.Points)-1].Time
+		tmax = b.TMax
 		collector.CollectBatch(b)
 	}
 	return nil