From 3945bf9dec03ddf708b28719738ddb18dba1f934 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@gmail.com>
Date: Tue, 14 Apr 2020 13:32:55 +0300
Subject: [PATCH] lib/promscrape: mention job name in error messages when
 target cannot be scraped

This should improve debuggability
---
 lib/promscrape/scrapework.go   | 13 +++++++++++--
 lib/promscrape/targetstatus.go |  6 +-----
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/lib/promscrape/scrapework.go b/lib/promscrape/scrapework.go
index 28b28530f..155e5f15e 100644
--- a/lib/promscrape/scrapework.go
+++ b/lib/promscrape/scrapework.go
@@ -60,6 +60,15 @@ type ScrapeWork struct {
 	SampleLimit int
 }
 
+// Job returns job for the ScrapeWork
+func (sw *ScrapeWork) Job() string {
+	label := promrelabel.GetLabelByName(sw.Labels, "job")
+	if label == nil {
+		return ""
+	}
+	return label.Value
+}
+
 type scrapeWork struct {
 	// Config for the scrape.
 	Config ScrapeWork
@@ -114,12 +123,12 @@ func (sw *scrapeWork) run(stopCh <-chan struct{}) {
 }
 
 func (sw *scrapeWork) logError(s string) {
-	logger.ErrorfSkipframes(1, "error when scraping %q: %s", sw.Config.ScrapeURL, s)
+	logger.ErrorfSkipframes(1, "error when scraping %q from job %q: %s", sw.Config.ScrapeURL, sw.Config.Job(), s)
 }
 
 func (sw *scrapeWork) scrapeAndLogError(timestamp int64) {
 	if err := sw.scrapeInternal(timestamp); err != nil {
-		logger.Errorf("error when scraping %q: %s", sw.Config.ScrapeURL, err)
+		logger.Errorf("error when scraping %q from job %q: %s", sw.Config.ScrapeURL, sw.Config.Job(), err)
 	}
 }
 
diff --git a/lib/promscrape/targetstatus.go b/lib/promscrape/targetstatus.go
index 0c3759006..b362d9a84 100644
--- a/lib/promscrape/targetstatus.go
+++ b/lib/promscrape/targetstatus.go
@@ -70,11 +70,7 @@ func (tsm *targetStatusMap) WriteHumanReadable(w io.Writer) {
 	byJob := make(map[string][]targetStatus)
 	tsm.mu.Lock()
 	for _, st := range tsm.m {
-		job := ""
-		label := promrelabel.GetLabelByName(st.sw.Labels, "job")
-		if label != nil {
-			job = label.Value
-		}
+		job := st.sw.Job()
 		byJob[job] = append(byJob[job], st)
 	}
 	tsm.mu.Unlock()