From e26e4b6e89e55cb30c76902e091b519e54b3feaa Mon Sep 17 00:00:00 2001
From: Fabian Reinartz <fab.reinartz@gmail.com>
Date: Fri, 12 Feb 2016 12:51:55 +0100
Subject: [PATCH] Restrict scrape timeout to interval length

---
 config/config.go                        | 3 +++
 config/config_test.go                   | 3 +++
 config/testdata/scrape_interval.bad.yml | 4 ++++
 3 files changed, 10 insertions(+)
 create mode 100644 config/testdata/scrape_interval.bad.yml

diff --git a/config/config.go b/config/config.go
index 19bec5423..73459b20d 100644
--- a/config/config.go
+++ b/config/config.go
@@ -266,6 +266,9 @@ func (c *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		if scfg.ScrapeTimeout == 0 {
 			scfg.ScrapeTimeout = c.GlobalConfig.ScrapeTimeout
 		}
+		if scfg.ScrapeTimeout > scfg.ScrapeInterval {
+			return fmt.Errorf("scrape timeout greater than scrape interval for scrape config with job name %q", scfg.JobName)
+		}
 
 		if _, ok := jobNames[scfg.JobName]; ok {
 			return fmt.Errorf("found multiple scrape configs with job name %q", scfg.JobName)
diff --git a/config/config_test.go b/config/config_test.go
index 477bee706..c0cc9a3ba 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -335,6 +335,9 @@ var expectedErrors = []struct {
 	}, {
 		filename: "jobname_dup.bad.yml",
 		errMsg:   `found multiple scrape configs with job name "prometheus"`,
+	}, {
+		filename: "scrape_interval.bad.yml",
+		errMsg:   `scrape timeout greater than scrape interval`,
 	}, {
 		filename: "labelname.bad.yml",
 		errMsg:   `"not$allowed" is not a valid label name`,
diff --git a/config/testdata/scrape_interval.bad.yml b/config/testdata/scrape_interval.bad.yml
new file mode 100644
index 000000000..b334c7775
--- /dev/null
+++ b/config/testdata/scrape_interval.bad.yml
@@ -0,0 +1,4 @@
+scrape_configs:
+- job_name: prometheus
+  scrape_interval: 5s
+  scrape_timeout:  6s