Mutex to avoid issues with concurrent scrapes

This is a hot fix
rnaveiras · Mar 7, 2019 · 292be20 · 292be20
1 parent c168625
commit 292be20
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,3 +1,9 @@
+## Version 0.2.5 / 2019-03-07
+
+[full changelog](https://github.com/rnaveiras/postgres_exporter/compare/v0.2.4...v0.2.5)
+
+* Mutex to avoid issues with concurrent scrapes ([#23](https://github.com/rnaveiras/postgres_exporter/pull/23))
+
 ## Version 0.2.4 / 2018-09-20
 
 [full changelog](https://github.com/rnaveiras/postgres_exporter/compare/v0.2.3...v0.2.4)

diff --git a/VERSION b/VERSION
@@ -1 +1 @@
-0.2.4
+0.2.5
diff --git a/postgres_exporter.go b/postgres_exporter.go
@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"os"
 	"strings"
+	"sync"
 
 	// _ "net/http/pprof"
 
@@ -27,6 +28,7 @@ const (
 
 var logger log.Logger
 var conn *pgx.Conn
+var handlerLock sync.Mutex
 
 var (
 	listenAddress = kingpin.Flag("web.listen-address", "Address on which to expose metrics and web interface.").Default("0.0.0.0:9187").String()
@@ -40,6 +42,9 @@ func init() {
 }
 
 func handler(w http.ResponseWriter, r *http.Request) {
+	handlerLock.Lock()
+	defer handlerLock.Unlock()
+
 	filters := r.URL.Query()["collect[]"]
 	level.Debug(logger).Log("component", "web", "query", strings.Join(filters, ","))