From 432187ac3b3372eea2a92885a0a8a0e99bd05b0c Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@gmail.com>
Date: Thu, 30 Apr 2020 02:15:39 +0300
Subject: [PATCH] app/vminsert: add `/-/reload` handler in the same way as for
 `vmagent`

---
 app/vmagent/main.go    | 8 +-------
 app/vminsert/main.go   | 8 ++++++++
 lib/procutil/signal.go | 9 +++++++++
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/app/vmagent/main.go b/app/vmagent/main.go
index 7b8501031f..ad0f3d0127 100644
--- a/app/vmagent/main.go
+++ b/app/vmagent/main.go
@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"net/http"
 	"strings"
-	"syscall"
 	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/app/vmagent/csvimport"
@@ -160,11 +159,7 @@ func requestHandler(w http.ResponseWriter, r *http.Request) bool {
 		return true
 	case "/-/reload":
 		promscrapeConfigReloadRequests.Inc()
-		if err := syscall.Kill(syscall.Getpid(), syscall.SIGHUP); err != nil {
-			promscrapeConfigReloadErrors.Inc()
-			httpserver.Errorf(w, "Fail to reload config file, %s", err)
-			return true
-		}
+		procutil.SelfSIGHUP()
 		w.WriteHeader(http.StatusNoContent)
 		return true
 	}
@@ -189,5 +184,4 @@ var (
 	promscrapeTargetsRequests = metrics.NewCounter(`vmagent_http_requests_total{path="/targets"}`)
 
 	promscrapeConfigReloadRequests = metrics.NewCounter(`vmagent_http_requests_total{path="/-/reload"}`)
-	promscrapeConfigReloadErrors   = metrics.NewCounter(`vmagent_http_request_errors_total{path="/-/reload"}`)
 )
diff --git a/app/vminsert/main.go b/app/vminsert/main.go
index 3b889a499e..29c340e18d 100644
--- a/app/vminsert/main.go
+++ b/app/vminsert/main.go
@@ -19,6 +19,7 @@ import (
 	influxserver "github.com/VictoriaMetrics/VictoriaMetrics/lib/ingestserver/influx"
 	opentsdbserver "github.com/VictoriaMetrics/VictoriaMetrics/lib/ingestserver/opentsdb"
 	opentsdbhttpserver "github.com/VictoriaMetrics/VictoriaMetrics/lib/ingestserver/opentsdbhttp"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/storage"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/writeconcurrencylimiter"
@@ -130,6 +131,11 @@ func RequestHandler(w http.ResponseWriter, r *http.Request) bool {
 		w.Header().Set("Content-Type", "text/plain")
 		promscrape.WriteHumanReadableTargetsStatus(w)
 		return true
+	case "/-/reload":
+		promscrapeConfigReloadRequests.Inc()
+		procutil.SelfSIGHUP()
+		w.WriteHeader(http.StatusNoContent)
+		return true
 	default:
 		// This is not our link
 		return false
@@ -152,4 +158,6 @@ var (
 	influxQueryRequests = metrics.NewCounter(`vm_http_requests_total{path="/query", protocol="influx"}`)
 
 	promscrapeTargetsRequests = metrics.NewCounter(`vm_http_requests_total{path="/targets"}`)
+
+	promscrapeConfigReloadRequests = metrics.NewCounter(`vm_http_requests_total{path="/-/reload"}`)
 )
diff --git a/lib/procutil/signal.go b/lib/procutil/signal.go
index 8221ecb679..c4483ab1f9 100644
--- a/lib/procutil/signal.go
+++ b/lib/procutil/signal.go
@@ -4,6 +4,8 @@ import (
 	"os"
 	"os/signal"
 	"syscall"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
 )
 
 // WaitForSigterm waits for either SIGTERM or SIGINT
@@ -24,3 +26,10 @@ func WaitForSigterm() os.Signal {
 		return sig
 	}
 }
+
+// SelfSIGHUP sends SIGHUP signal to the current process.
+func SelfSIGHUP() {
+	if err := syscall.Kill(syscall.Getpid(), syscall.SIGHUP); err != nil {
+		logger.Panicf("FATAL: cannot send SIGHUP to itself: %s", err)
+	}
+}