From 4c4f51d546c117c007e31b7c486c634b54ef16db Mon Sep 17 00:00:00 2001
From: beorn7 <beorn@soundcloud.com>
Date: Thu, 19 Feb 2015 02:01:06 +0100
Subject: [PATCH] Catch illegal label names for summaries in histograms.

---
 prometheus/summary.go | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/prometheus/summary.go b/prometheus/summary.go
index 0626d08..2d4bc55 100644
--- a/prometheus/summary.go
+++ b/prometheus/summary.go
@@ -163,6 +163,17 @@ func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
 		panic(errInconsistentCardinality)
 	}
 
+	for _, n := range desc.variableLabels {
+		if n == "quantile" {
+			panic("'quantile' is not allowed as label name in summaries")
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == "quantile" {
+			panic("'quantile' is not allowed as label name in summaries")
+		}
+	}
+
 	if len(opts.Objectives) == 0 {
 		opts.Objectives = DefObjectives
 	}