Add context to "duplicate label names" to enable debugging (#1177)

SpencerMalone · web-flow · commit 3d765a161a28 · 2022-12-13T11:39:55.000+01:00
* Add context to "duplicate label names" to enable debugging

Signed-off-by: SpencerMalone &lt;malone.spencer@gmail.com&gt;

* Remove unused errors package import.

Signed-off-by: SpencerMalone &lt;malone.spencer@gmail.com&gt;

Signed-off-by: SpencerMalone &lt;malone.spencer@gmail.com&gt;
diff --git a/prometheus/desc.go b/prometheus/desc.go
@@ -14,7 +14,6 @@
 package prometheus
 
 import (
-	"errors"
 	"fmt"
 	"sort"
 	"strings"
@@ -127,7 +126,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *
 		labelNameSet[labelName] = struct{}{}
 	}
 	if len(labelNames) != len(labelNameSet) {
-		d.err = errors.New("duplicate label names")
+		d.err = fmt.Errorf("duplicate label names in constant and variable labels for metric %q", fqName)
 		return d
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -14,7 +14,6 @@`
`14`	`14`	`package prometheus`
`15`	`15`
`16`	`16`	`import (`
`17`		`- "errors"`
`18`	`17`	`"fmt"`
`19`	`18`	`"sort"`
`20`	`19`	`"strings"`
`@@ -127,7 +126,7 @@ func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *`
`127`	`126`	`labelNameSet[labelName] = struct{}{}`
`128`	`127`	`}`
`129`	`128`	`if len(labelNames) != len(labelNameSet) {`
`130`		`- d.err = errors.New("duplicate label names")`
	`129`	`+ d.err = fmt.Errorf("duplicate label names in constant and variable labels for metric %q", fqName)`
`131`	`130`	`return d`
`132`	`131`	`}`
`133`	`132`