From 8d32005ede0cda3d83277b8c3e44a86766fa3dbe Mon Sep 17 00:00:00 2001
From: Cody Soyland <cody@soyland.org>
Date: Thu, 2 Jan 2020 15:43:34 -0600
Subject: [PATCH] Initialize expvar lazily to prevent panic if importing both
 Pilosa v1 and v2.

---
 stats/stats.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/stats/stats.go b/stats/stats.go
index 9c6944d4e..c360baab0 100644
--- a/stats/stats.go
+++ b/stats/stats.go
@@ -25,7 +25,7 @@ import (
 )
 
 // Expvar global expvar map.
-var Expvar = expvar.NewMap("index")
+var Expvar *expvar.Map
 
 // StatsClient represents a client to a stats server.
 type StatsClient interface {
@@ -90,6 +90,9 @@ type expvarStatsClient struct {
 // NewExpvarStatsClient returns a new instance of ExpvarStatsClient.
 // This client points at the root of the expvar index map.
 func NewExpvarStatsClient() *expvarStatsClient {
+	if Expvar == nil {
+		Expvar = expvar.NewMap("index")
+	}
 	return &expvarStatsClient{
 		m: Expvar,
 	}