lib/promrelabel: prevent panic caused by invalid label name or value in debug interface

### Describe Your Changes Previously, invalid label name or value could cause a panic of vmselect or vmsingle as it was using MustNewLabelsFromString which was added for usage in tests only. Fix this by properly handling and propagating error to user interface if there is any. See: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/8661 Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
2026-05-17 00:26:36 +03:00 · 2025-05-30 21:22:48 +04:00
parent b1582b3012
commit aef59d9281
5 changed files with 369 additions and 248 deletions
--- a/app/vmui/packages/vmui/src/pages/Relabel/index.tsx
+++ b/app/vmui/packages/vmui/src/pages/Relabel/index.tsx
@@ -154,13 +154,13 @@ const Relabel: FC = () => {
              <div className="vm-relabeling-steps-item__row">
                <span>Input Labels:</span>
                <code>
-                  <pre dangerouslySetInnerHTML={{ __html: step.inLabels }}/>
+                  <pre dangerouslySetInnerHTML={{ __html: step.errors?.inLabels || step.inLabels }}/>
                </code>
              </div>
              <div className="vm-relabeling-steps-item__row">
                <span>Output labels:</span>
                <code>
-                  <pre dangerouslySetInnerHTML={{ __html: step.outLabels }}/>
+                  <pre dangerouslySetInnerHTML={{ __html: step.errors?.outLabels || step.outLabels }}/>
                </code>
              </div>
            </div>
--- a/app/vmui/packages/vmui/src/types/index.ts
+++ b/app/vmui/packages/vmui/src/types/index.ts
@@ -138,6 +138,10 @@ export interface RelabelStep {
  rule: string;
  inLabels: string;
  outLabels: string;
+  errors: {
+    inLabels: string;
+    outLabels: string;
+  }
 }

 export interface RelabelData {
--- a/docs/victoriametrics/changelog/CHANGELOG.md
+++ b/docs/victoriametrics/changelog/CHANGELOG.md
@@ -26,6 +26,7 @@ See also [LTS releases](https://docs.victoriametrics.com/victoriametrics/lts-rel
 * BUGFIX: [vmalert-tool](https://docs.victoriametrics.com/victoriametrics/vmalert-tool/): fix access conflicts for the temporary test folder when multiple users run tests on the same host. Thanks to @evkuzin for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/9015).
 * BUGFIX: [alerts](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/deployment/docker/rules): fix the alerting rule `ScrapePoolHasNoTargets`. Previously, it may cause false positive in [sharding mode](https://docs.victoriametrics.com/victoriametrics/vmagent/#scraping-big-number-of-targets).
 * BUGFIX: [vmsingle](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/) and  `vmstorage` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/cluster-victoriametrics/): fixed a regression in downsampling logic introduced in [#7440](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7440) and released in [v1.106.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.106.0), where downsampling rules with filters `filter:offset:interval` could be incorrectly skipped in favor of unfiltered rules `offset:interval`. See [#8969](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/8969).
+* BUGFIX: [vmsingle](https://docs.victoriametrics.com/victoriametrics/single-server-victoriametrics/) and `vmselect` in [VictoriaMetrics cluster](https://docs.victoriametrics.com/cluster-victoriametrics/): prevent panic caused by invalid label name in metric relabeling debugging interface. Error is now properly propagated and displayed in the interface. See [#8661](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/8661).

 ## [v1.118.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.118.0)

--- a/lib/promrelabel/debug.qtpl
+++ b/lib/promrelabel/debug.qtpl
@@ -100,22 +100,36 @@ function submitRelabelDebugForm(e) {
  <tbody>
        {% for i, ds := range dss %}
        {% code
-                inLabels := promutil.MustNewLabelsFromString(ds.In)
-                outLabels := promutil.MustNewLabelsFromString(ds.Out)
+                inLabels, inErr := promutil.NewLabelsFromString(ds.In)
+                outLabels, outErr := promutil.NewLabelsFromString(ds.Out)
                changedLabels := getChangedLabelNames(inLabels, outLabels)
        %}
        <tr>
                <td>{%d i %}</td>
                <td><b><pre class="m-2">{%s ds.Rule %}</pre></b></td>
                <td>
-                    <div class="m-2" style="font-size: 0.9em" title="deleted and updated labels highlighted in red">
-                        {%= labelsWithHighlight(inLabels, changedLabels, "#D15757") %}
-                    </div>
+                    {% if inErr == nil %}
+                        <div class="m-2" style="font-size: 0.9em" title="deleted and updated labels highlighted in red">
+                            {%= labelsWithHighlight(inLabels, changedLabels, "#D15757") %}
+                        </div>
+                    {% else %}
+                        <div class="m-2" style="font-size: 0.9em; color: red" title="error parsing input labels">
+                            <pre>{%s inErr.Error() %}</pre>
+                        </div>
+                        {% break %}
+                    {% endif %}
                </td>
                <td>
-                    <div class="m-2" style="font-size: 0.9em" title="added and updated labels highlighted in blue">
-                        {%= labelsWithHighlight(outLabels, changedLabels, "#4495e0") %}
-                    </div>
+                    {% if outErr == nil %}
+                        <div class="m-2" style="font-size: 0.9em" title="added and updated labels highlighted in blue">
+                            {%= labelsWithHighlight(outLabels, changedLabels, "#4495e0") %}
+                        </div>
+                    {% else %}
+                        <div class="m-2" style="font-size: 0.9em; color: red" title="error parsing output labels">
+                            <pre>{%s outErr.Error() %}</pre>
+                        </div>
+                        {% break %}
+                    {% endif %}
                </td>
        </tr>
        {% endfor %}
@@ -143,26 +157,39 @@ function submitRelabelDebugForm(e) {
        "status": "error",
        "error": {%q= fmt.Sprintf("Error: %s", err) %}
    {% else %}
+        {% code var hasError bool %}
        "status": "success",
-        {% if len(dss) > 0 %}
-            "originalLabels": {%q= mustFormatLabels(dss[0].In) %},
-            "resultingLabels": {%q= mustFormatLabels(dss[len(dss)-1].Out) %},
-        {% endif %}
        "steps": [
            {% for i, ds := range dss %}
                {% code
-                    inLabels := promutil.MustNewLabelsFromString(ds.In)
-                    outLabels := promutil.MustNewLabelsFromString(ds.Out)
+                    inLabels, inErr := promutil.NewLabelsFromString(ds.In)
+                    outLabels, outErr := promutil.NewLabelsFromString(ds.Out)
                    changedLabels := getChangedLabelNames(inLabels, outLabels)
                %}
                {
                    "inLabels": {%q= labelsWithHighlight(inLabels, changedLabels, "#D15757") %},
                    "outLabels": {%q= labelsWithHighlight(outLabels, changedLabels, "#4495e0") %},
-                    "rule": {%q= ds.Rule %}
+                    "rule": {%q= ds.Rule %},
+                    "errors": {
+                        {% if inErr != nil %}
+                        "inLabels": {%q= `<span style="color: #D15757">`+inErr.Error()+`</span>` %}{% if outErr != nil %},{% endif %}
+                        {%code hasError = true %}
+                        {% else %}
+                        {% endif %}
+                        {% if outErr != nil %}
+                        "outLabels": {%q= `<span style="color: #D15757">`+outErr.Error()+`</span>` %}
+                        {%code hasError = true %}
+                        {% endif %}
+                    }
                }
                {% if i != len(dss)-1 %},{% endif %}
            {% endfor %}
        ]
+        {% if len(dss) > 0 && !hasError %}
+        ,
+          "originalLabels": {%q= mustFormatLabels(dss[0].In) %},
+          "resultingLabels": {%q= mustFormatLabels(dss[len(dss)-1].Out) %}
+        {% endif %}
    {% endif %}
 }
 {% endfunc %}
@@ -200,8 +227,12 @@ function submitRelabelDebugForm(e) {
 {% endfunc %}

 {% func mustFormatLabels(s string) %}
-        {% code labels := promutil.MustNewLabelsFromString(s) %}
-        {%= labelsWithHighlight(labels, nil, "") %}
+        {% code labels, err := promutil.NewLabelsFromString(s) %}
+        {% if err != nil %}
+            <span style="color: red" title="error parsing labels: {%s err.Error() %}">{%s "error parsing labels: " + err.Error() %}</span>
+        {% else %}
+            {%= labelsWithHighlight(labels, nil, "") %}
+        {% endif %}
 {% endfunc %}

 {% endstripspace %}
--- a/lib/promrelabel/debug.qtpl.go
+++ b/lib/promrelabel/debug.qtpl.go
@@ -236,8 +236,8 @@ func streamrelabelDebugSteps(qw422016 *qt422016.Writer, dss []DebugStep, targetU
 //line lib/promrelabel/debug.qtpl:101
 	for i, ds := range dss {
 //line lib/promrelabel/debug.qtpl:103
-		inLabels := promutil.MustNewLabelsFromString(ds.In)
-		outLabels := promutil.MustNewLabelsFromString(ds.Out)
+		inLabels, inErr := promutil.NewLabelsFromString(ds.In)
+		outLabels, outErr := promutil.NewLabelsFromString(ds.Out)
 		changedLabels := getChangedLabelNames(inLabels, outLabels)

 //line lib/promrelabel/debug.qtpl:106
@@ -249,189 +249,258 @@ func streamrelabelDebugSteps(qw422016 *qt422016.Writer, dss []DebugStep, targetU
 //line lib/promrelabel/debug.qtpl:109
 		qw422016.E().S(ds.Rule)
 //line lib/promrelabel/debug.qtpl:109
-		qw422016.N().S(`</pre></b></td><td><div class="m-2" style="font-size: 0.9em" title="deleted and updated labels highlighted in red">`)
-//line lib/promrelabel/debug.qtpl:112
-		streamlabelsWithHighlight(qw422016, inLabels, changedLabels, "#D15757")
-//line lib/promrelabel/debug.qtpl:112
-		qw422016.N().S(`</div></td><td><div class="m-2" style="font-size: 0.9em" title="added and updated labels highlighted in blue">`)
-//line lib/promrelabel/debug.qtpl:117
-		streamlabelsWithHighlight(qw422016, outLabels, changedLabels, "#4495e0")
-//line lib/promrelabel/debug.qtpl:117
-		qw422016.N().S(`</div></td></tr>`)
-//line lib/promrelabel/debug.qtpl:121
-	}
-//line lib/promrelabel/debug.qtpl:121
-	qw422016.N().S(`</tbody></table>`)
-//line lib/promrelabel/debug.qtpl:124
-	if len(dss) > 0 {
-//line lib/promrelabel/debug.qtpl:124
-		qw422016.N().S(`<div class="m-3"><b>Resulting labels:</b> <samp>`)
-//line lib/promrelabel/debug.qtpl:126
-		streammustFormatLabels(qw422016, dss[len(dss)-1].Out)
-//line lib/promrelabel/debug.qtpl:126
-		qw422016.N().S(`</samp>`)
-//line lib/promrelabel/debug.qtpl:127
-		if targetURL != "" {
-//line lib/promrelabel/debug.qtpl:127
-			qw422016.N().S(`<div><b>Target URL:</b>`)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.N().S(` `)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.N().S(`<a href="`)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.E().S(targetURL)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.N().S(`" target="_blank">`)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.E().S(targetURL)
-//line lib/promrelabel/debug.qtpl:129
-			qw422016.N().S(`</a>`)
-//line lib/promrelabel/debug.qtpl:130
-			if targetID != "" {
-//line lib/promrelabel/debug.qtpl:131
-				qw422016.N().S(` `)
-//line lib/promrelabel/debug.qtpl:131
-				qw422016.N().S(`(<a href="target_response?id=`)
-//line lib/promrelabel/debug.qtpl:132
-				qw422016.E().S(targetID)
-//line lib/promrelabel/debug.qtpl:132
-				qw422016.N().S(`" target="_blank" title="click to fetch target response on behalf of the scraper">response</a>)`)
-//line lib/promrelabel/debug.qtpl:133
-			}
-//line lib/promrelabel/debug.qtpl:133
+		qw422016.N().S(`</pre></b></td><td>`)
+//line lib/promrelabel/debug.qtpl:111
+		if inErr == nil {
+//line lib/promrelabel/debug.qtpl:111
+			qw422016.N().S(`<div class="m-2" style="font-size: 0.9em" title="deleted and updated labels highlighted in red">`)
+//line lib/promrelabel/debug.qtpl:113
+			streamlabelsWithHighlight(qw422016, inLabels, changedLabels, "#D15757")
+//line lib/promrelabel/debug.qtpl:113
 			qw422016.N().S(`</div>`)
-//line lib/promrelabel/debug.qtpl:135
+//line lib/promrelabel/debug.qtpl:115
+		} else {
+//line lib/promrelabel/debug.qtpl:115
+			qw422016.N().S(`<div class="m-2" style="font-size: 0.9em; color: red" title="error parsing input labels"><pre>`)
+//line lib/promrelabel/debug.qtpl:117
+			qw422016.E().S(inErr.Error())
+//line lib/promrelabel/debug.qtpl:117
+			qw422016.N().S(`</pre></div>`)
+//line lib/promrelabel/debug.qtpl:119
+			break
+//line lib/promrelabel/debug.qtpl:120
 		}
+//line lib/promrelabel/debug.qtpl:120
+		qw422016.N().S(`</td><td>`)
+//line lib/promrelabel/debug.qtpl:123
+		if outErr == nil {
+//line lib/promrelabel/debug.qtpl:123
+			qw422016.N().S(`<div class="m-2" style="font-size: 0.9em" title="added and updated labels highlighted in blue">`)
+//line lib/promrelabel/debug.qtpl:125
+			streamlabelsWithHighlight(qw422016, outLabels, changedLabels, "#4495e0")
+//line lib/promrelabel/debug.qtpl:125
+			qw422016.N().S(`</div>`)
+//line lib/promrelabel/debug.qtpl:127
+		} else {
+//line lib/promrelabel/debug.qtpl:127
+			qw422016.N().S(`<div class="m-2" style="font-size: 0.9em; color: red" title="error parsing output labels"><pre>`)
+//line lib/promrelabel/debug.qtpl:129
+			qw422016.E().S(outErr.Error())
+//line lib/promrelabel/debug.qtpl:129
+			qw422016.N().S(`</pre></div>`)
+//line lib/promrelabel/debug.qtpl:131
+			break
+//line lib/promrelabel/debug.qtpl:132
+		}
+//line lib/promrelabel/debug.qtpl:132
+		qw422016.N().S(`</td></tr>`)
 //line lib/promrelabel/debug.qtpl:135
-		qw422016.N().S(`</div>`)
-//line lib/promrelabel/debug.qtpl:137
 	}
+//line lib/promrelabel/debug.qtpl:135
+	qw422016.N().S(`</tbody></table>`)
 //line lib/promrelabel/debug.qtpl:138
-}
-
+	if len(dss) > 0 {
 //line lib/promrelabel/debug.qtpl:138
-func writerelabelDebugSteps(qq422016 qtio422016.Writer, dss []DebugStep, targetURL, targetID string) {
-//line lib/promrelabel/debug.qtpl:138
-	qw422016 := qt422016.AcquireWriter(qq422016)
-//line lib/promrelabel/debug.qtpl:138
-	streamrelabelDebugSteps(qw422016, dss, targetURL, targetID)
-//line lib/promrelabel/debug.qtpl:138
-	qt422016.ReleaseWriter(qw422016)
-//line lib/promrelabel/debug.qtpl:138
-}
-
-//line lib/promrelabel/debug.qtpl:138
-func relabelDebugSteps(dss []DebugStep, targetURL, targetID string) string {
-//line lib/promrelabel/debug.qtpl:138
-	qb422016 := qt422016.AcquireByteBuffer()
-//line lib/promrelabel/debug.qtpl:138
-	writerelabelDebugSteps(qb422016, dss, targetURL, targetID)
-//line lib/promrelabel/debug.qtpl:138
-	qs422016 := string(qb422016.B)
-//line lib/promrelabel/debug.qtpl:138
-	qt422016.ReleaseByteBuffer(qb422016)
-//line lib/promrelabel/debug.qtpl:138
-	return qs422016
-//line lib/promrelabel/debug.qtpl:138
-}
-
+		qw422016.N().S(`<div class="m-3"><b>Resulting labels:</b> <samp>`)
 //line lib/promrelabel/debug.qtpl:140
-func StreamRelabelDebugStepsJSON(qw422016 *qt422016.Writer, targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) {
+		streammustFormatLabels(qw422016, dss[len(dss)-1].Out)
 //line lib/promrelabel/debug.qtpl:140
-	qw422016.N().S(`{`)
-//line lib/promrelabel/debug.qtpl:142
-	if err != nil {
-//line lib/promrelabel/debug.qtpl:142
-		qw422016.N().S(`"status": "error","error":`)
+		qw422016.N().S(`</samp>`)
+//line lib/promrelabel/debug.qtpl:141
+		if targetURL != "" {
+//line lib/promrelabel/debug.qtpl:141
+			qw422016.N().S(`<div><b>Target URL:</b>`)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.N().S(` `)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.N().S(`<a href="`)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.E().S(targetURL)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.N().S(`" target="_blank">`)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.E().S(targetURL)
+//line lib/promrelabel/debug.qtpl:143
+			qw422016.N().S(`</a>`)
 //line lib/promrelabel/debug.qtpl:144
-		qw422016.N().Q(fmt.Sprintf("Error: %s", err))
+			if targetID != "" {
 //line lib/promrelabel/debug.qtpl:145
-	} else {
+				qw422016.N().S(` `)
 //line lib/promrelabel/debug.qtpl:145
-		qw422016.N().S(`"status": "success",`)
+				qw422016.N().S(`(<a href="target_response?id=`)
+//line lib/promrelabel/debug.qtpl:146
+				qw422016.E().S(targetID)
+//line lib/promrelabel/debug.qtpl:146
+				qw422016.N().S(`" target="_blank" title="click to fetch target response on behalf of the scraper">response</a>)`)
 //line lib/promrelabel/debug.qtpl:147
-		if len(dss) > 0 {
+			}
 //line lib/promrelabel/debug.qtpl:147
-			qw422016.N().S(`"originalLabels":`)
-//line lib/promrelabel/debug.qtpl:148
-			qw422016.N().Q(mustFormatLabels(dss[0].In))
-//line lib/promrelabel/debug.qtpl:148
-			qw422016.N().S(`,"resultingLabels":`)
+			qw422016.N().S(`</div>`)
 //line lib/promrelabel/debug.qtpl:149
-			qw422016.N().Q(mustFormatLabels(dss[len(dss)-1].Out))
-//line lib/promrelabel/debug.qtpl:149
-			qw422016.N().S(`,`)
-//line lib/promrelabel/debug.qtpl:150
 		}
-//line lib/promrelabel/debug.qtpl:150
-		qw422016.N().S(`"steps": [`)
+//line lib/promrelabel/debug.qtpl:149
+		qw422016.N().S(`</div>`)
+//line lib/promrelabel/debug.qtpl:151
+	}
 //line lib/promrelabel/debug.qtpl:152
-		for i, ds := range dss {
+}
+
+//line lib/promrelabel/debug.qtpl:152
+func writerelabelDebugSteps(qq422016 qtio422016.Writer, dss []DebugStep, targetURL, targetID string) {
+//line lib/promrelabel/debug.qtpl:152
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line lib/promrelabel/debug.qtpl:152
+	streamrelabelDebugSteps(qw422016, dss, targetURL, targetID)
+//line lib/promrelabel/debug.qtpl:152
+	qt422016.ReleaseWriter(qw422016)
+//line lib/promrelabel/debug.qtpl:152
+}
+
+//line lib/promrelabel/debug.qtpl:152
+func relabelDebugSteps(dss []DebugStep, targetURL, targetID string) string {
+//line lib/promrelabel/debug.qtpl:152
+	qb422016 := qt422016.AcquireByteBuffer()
+//line lib/promrelabel/debug.qtpl:152
+	writerelabelDebugSteps(qb422016, dss, targetURL, targetID)
+//line lib/promrelabel/debug.qtpl:152
+	qs422016 := string(qb422016.B)
+//line lib/promrelabel/debug.qtpl:152
+	qt422016.ReleaseByteBuffer(qb422016)
+//line lib/promrelabel/debug.qtpl:152
+	return qs422016
+//line lib/promrelabel/debug.qtpl:152
+}
+
 //line lib/promrelabel/debug.qtpl:154
-			inLabels := promutil.MustNewLabelsFromString(ds.In)
-			outLabels := promutil.MustNewLabelsFromString(ds.Out)
+func StreamRelabelDebugStepsJSON(qw422016 *qt422016.Writer, targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) {
+//line lib/promrelabel/debug.qtpl:154
+	qw422016.N().S(`{`)
+//line lib/promrelabel/debug.qtpl:156
+	if err != nil {
+//line lib/promrelabel/debug.qtpl:156
+		qw422016.N().S(`"status": "error","error":`)
+//line lib/promrelabel/debug.qtpl:158
+		qw422016.N().Q(fmt.Sprintf("Error: %s", err))
+//line lib/promrelabel/debug.qtpl:159
+	} else {
+//line lib/promrelabel/debug.qtpl:160
+		var hasError bool
+
+//line lib/promrelabel/debug.qtpl:160
+		qw422016.N().S(`"status": "success","steps": [`)
+//line lib/promrelabel/debug.qtpl:163
+		for i, ds := range dss {
+//line lib/promrelabel/debug.qtpl:165
+			inLabels, inErr := promutil.NewLabelsFromString(ds.In)
+			outLabels, outErr := promutil.NewLabelsFromString(ds.Out)
 			changedLabels := getChangedLabelNames(inLabels, outLabels)

-//line lib/promrelabel/debug.qtpl:157
+//line lib/promrelabel/debug.qtpl:168
 			qw422016.N().S(`{"inLabels":`)
-//line lib/promrelabel/debug.qtpl:159
-			qw422016.N().Q(labelsWithHighlight(inLabels, changedLabels, "#D15757"))
-//line lib/promrelabel/debug.qtpl:159
-			qw422016.N().S(`,"outLabels":`)
-//line lib/promrelabel/debug.qtpl:160
-			qw422016.N().Q(labelsWithHighlight(outLabels, changedLabels, "#4495e0"))
-//line lib/promrelabel/debug.qtpl:160
-			qw422016.N().S(`,"rule":`)
-//line lib/promrelabel/debug.qtpl:161
-			qw422016.N().Q(ds.Rule)
-//line lib/promrelabel/debug.qtpl:161
-			qw422016.N().S(`}`)
-//line lib/promrelabel/debug.qtpl:163
-			if i != len(dss)-1 {
-//line lib/promrelabel/debug.qtpl:163
-				qw422016.N().S(`,`)
-//line lib/promrelabel/debug.qtpl:163
-			}
-//line lib/promrelabel/debug.qtpl:164
-		}
-//line lib/promrelabel/debug.qtpl:164
-		qw422016.N().S(`]`)
-//line lib/promrelabel/debug.qtpl:166
-	}
-//line lib/promrelabel/debug.qtpl:166
-	qw422016.N().S(`}`)
-//line lib/promrelabel/debug.qtpl:168
-}
-
-//line lib/promrelabel/debug.qtpl:168
-func WriteRelabelDebugStepsJSON(qq422016 qtio422016.Writer, targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) {
-//line lib/promrelabel/debug.qtpl:168
-	qw422016 := qt422016.AcquireWriter(qq422016)
-//line lib/promrelabel/debug.qtpl:168
-	StreamRelabelDebugStepsJSON(qw422016, targetURL, targetID, dss, metric, relabelConfigs, err)
-//line lib/promrelabel/debug.qtpl:168
-	qt422016.ReleaseWriter(qw422016)
-//line lib/promrelabel/debug.qtpl:168
-}
-
-//line lib/promrelabel/debug.qtpl:168
-func RelabelDebugStepsJSON(targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) string {
-//line lib/promrelabel/debug.qtpl:168
-	qb422016 := qt422016.AcquireByteBuffer()
-//line lib/promrelabel/debug.qtpl:168
-	WriteRelabelDebugStepsJSON(qb422016, targetURL, targetID, dss, metric, relabelConfigs, err)
-//line lib/promrelabel/debug.qtpl:168
-	qs422016 := string(qb422016.B)
-//line lib/promrelabel/debug.qtpl:168
-	qt422016.ReleaseByteBuffer(qb422016)
-//line lib/promrelabel/debug.qtpl:168
-	return qs422016
-//line lib/promrelabel/debug.qtpl:168
-}
-
 //line lib/promrelabel/debug.qtpl:170
-func streamlabelsWithHighlight(qw422016 *qt422016.Writer, labels *promutil.Labels, highlight map[string]struct{}, color string) {
+			qw422016.N().Q(labelsWithHighlight(inLabels, changedLabels, "#D15757"))
+//line lib/promrelabel/debug.qtpl:170
+			qw422016.N().S(`,"outLabels":`)
+//line lib/promrelabel/debug.qtpl:171
+			qw422016.N().Q(labelsWithHighlight(outLabels, changedLabels, "#4495e0"))
+//line lib/promrelabel/debug.qtpl:171
+			qw422016.N().S(`,"rule":`)
 //line lib/promrelabel/debug.qtpl:172
+			qw422016.N().Q(ds.Rule)
+//line lib/promrelabel/debug.qtpl:172
+			qw422016.N().S(`,"errors": {`)
+//line lib/promrelabel/debug.qtpl:174
+			if inErr != nil {
+//line lib/promrelabel/debug.qtpl:174
+				qw422016.N().S(`"inLabels":`)
+//line lib/promrelabel/debug.qtpl:175
+				qw422016.N().Q(`<span style="color: #D15757">` + inErr.Error() + `</span>`)
+//line lib/promrelabel/debug.qtpl:175
+				if outErr != nil {
+//line lib/promrelabel/debug.qtpl:175
+					qw422016.N().S(`,`)
+//line lib/promrelabel/debug.qtpl:175
+				}
+//line lib/promrelabel/debug.qtpl:176
+				hasError = true
+
+//line lib/promrelabel/debug.qtpl:177
+			} else {
+//line lib/promrelabel/debug.qtpl:178
+			}
+//line lib/promrelabel/debug.qtpl:179
+			if outErr != nil {
+//line lib/promrelabel/debug.qtpl:179
+				qw422016.N().S(`"outLabels":`)
+//line lib/promrelabel/debug.qtpl:180
+				qw422016.N().Q(`<span style="color: #D15757">` + outErr.Error() + `</span>`)
+//line lib/promrelabel/debug.qtpl:181
+				hasError = true
+
+//line lib/promrelabel/debug.qtpl:182
+			}
+//line lib/promrelabel/debug.qtpl:182
+			qw422016.N().S(`}}`)
+//line lib/promrelabel/debug.qtpl:185
+			if i != len(dss)-1 {
+//line lib/promrelabel/debug.qtpl:185
+				qw422016.N().S(`,`)
+//line lib/promrelabel/debug.qtpl:185
+			}
+//line lib/promrelabel/debug.qtpl:186
+		}
+//line lib/promrelabel/debug.qtpl:186
+		qw422016.N().S(`]`)
+//line lib/promrelabel/debug.qtpl:188
+		if len(dss) > 0 && !hasError {
+//line lib/promrelabel/debug.qtpl:188
+			qw422016.N().S(`,"originalLabels":`)
+//line lib/promrelabel/debug.qtpl:190
+			qw422016.N().Q(mustFormatLabels(dss[0].In))
+//line lib/promrelabel/debug.qtpl:190
+			qw422016.N().S(`,"resultingLabels":`)
+//line lib/promrelabel/debug.qtpl:191
+			qw422016.N().Q(mustFormatLabels(dss[len(dss)-1].Out))
+//line lib/promrelabel/debug.qtpl:191
+			qw422016.N().S(`,`)
+//line lib/promrelabel/debug.qtpl:192
+		}
+//line lib/promrelabel/debug.qtpl:193
+	}
+//line lib/promrelabel/debug.qtpl:193
+	qw422016.N().S(`}`)
+//line lib/promrelabel/debug.qtpl:195
+}
+
+//line lib/promrelabel/debug.qtpl:195
+func WriteRelabelDebugStepsJSON(qq422016 qtio422016.Writer, targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) {
+//line lib/promrelabel/debug.qtpl:195
+	qw422016 := qt422016.AcquireWriter(qq422016)
+//line lib/promrelabel/debug.qtpl:195
+	StreamRelabelDebugStepsJSON(qw422016, targetURL, targetID, dss, metric, relabelConfigs, err)
+//line lib/promrelabel/debug.qtpl:195
+	qt422016.ReleaseWriter(qw422016)
+//line lib/promrelabel/debug.qtpl:195
+}
+
+//line lib/promrelabel/debug.qtpl:195
+func RelabelDebugStepsJSON(targetURL, targetID string, dss []DebugStep, metric, relabelConfigs string, err error) string {
+//line lib/promrelabel/debug.qtpl:195
+	qb422016 := qt422016.AcquireByteBuffer()
+//line lib/promrelabel/debug.qtpl:195
+	WriteRelabelDebugStepsJSON(qb422016, targetURL, targetID, dss, metric, relabelConfigs, err)
+//line lib/promrelabel/debug.qtpl:195
+	qs422016 := string(qb422016.B)
+//line lib/promrelabel/debug.qtpl:195
+	qt422016.ReleaseByteBuffer(qb422016)
+//line lib/promrelabel/debug.qtpl:195
+	return qs422016
+//line lib/promrelabel/debug.qtpl:195
+}
+
+//line lib/promrelabel/debug.qtpl:197
+func streamlabelsWithHighlight(qw422016 *qt422016.Writer, labels *promutil.Labels, highlight map[string]struct{}, color string) {
+//line lib/promrelabel/debug.qtpl:199
 	labelsList := labels.GetLabels()
 	metricName := ""
 	for i, label := range labelsList {
@@ -442,137 +511,153 @@ func streamlabelsWithHighlight(qw422016 *qt422016.Writer, labels *promutil.Label
 		}
 	}

-//line lib/promrelabel/debug.qtpl:182
+//line lib/promrelabel/debug.qtpl:209
 	if metricName != "" {
-//line lib/promrelabel/debug.qtpl:183
+//line lib/promrelabel/debug.qtpl:210
 		if _, ok := highlight["__name__"]; ok {
-//line lib/promrelabel/debug.qtpl:183
+//line lib/promrelabel/debug.qtpl:210
 			qw422016.N().S(`<span style="font-weight:bold;color:`)
-//line lib/promrelabel/debug.qtpl:184
+//line lib/promrelabel/debug.qtpl:211
 			qw422016.E().S(color)
-//line lib/promrelabel/debug.qtpl:184
+//line lib/promrelabel/debug.qtpl:211
 			qw422016.N().S(`">`)
-//line lib/promrelabel/debug.qtpl:184
+//line lib/promrelabel/debug.qtpl:211
 			qw422016.E().S(metricName)
-//line lib/promrelabel/debug.qtpl:184
+//line lib/promrelabel/debug.qtpl:211
 			qw422016.N().S(`</span>`)
-//line lib/promrelabel/debug.qtpl:185
+//line lib/promrelabel/debug.qtpl:212
 		} else {
-//line lib/promrelabel/debug.qtpl:186
+//line lib/promrelabel/debug.qtpl:213
 			qw422016.E().S(metricName)
-//line lib/promrelabel/debug.qtpl:187
+//line lib/promrelabel/debug.qtpl:214
 		}
-//line lib/promrelabel/debug.qtpl:188
+//line lib/promrelabel/debug.qtpl:215
 		if len(labelsList) == 0 {
-//line lib/promrelabel/debug.qtpl:188
+//line lib/promrelabel/debug.qtpl:215
 			return
-//line lib/promrelabel/debug.qtpl:188
+//line lib/promrelabel/debug.qtpl:215
 		}
-//line lib/promrelabel/debug.qtpl:189
+//line lib/promrelabel/debug.qtpl:216
 	}
-//line lib/promrelabel/debug.qtpl:189
+//line lib/promrelabel/debug.qtpl:216
 	qw422016.N().S(`{`)
-//line lib/promrelabel/debug.qtpl:191
+//line lib/promrelabel/debug.qtpl:218
 	for i, label := range labelsList {
-//line lib/promrelabel/debug.qtpl:192
+//line lib/promrelabel/debug.qtpl:219
 		if _, ok := highlight[label.Name]; ok {
-//line lib/promrelabel/debug.qtpl:192
+//line lib/promrelabel/debug.qtpl:219
 			qw422016.N().S(`<span style="font-weight:bold;color:`)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.E().S(color)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.N().S(`">`)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.E().S(label.Name)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.N().S(`=`)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.E().Q(label.Value)
-//line lib/promrelabel/debug.qtpl:193
+//line lib/promrelabel/debug.qtpl:220
 			qw422016.N().S(`</span>`)
-//line lib/promrelabel/debug.qtpl:194
+//line lib/promrelabel/debug.qtpl:221
 		} else {
-//line lib/promrelabel/debug.qtpl:195
+//line lib/promrelabel/debug.qtpl:222
 			qw422016.E().S(label.Name)
-//line lib/promrelabel/debug.qtpl:195
+//line lib/promrelabel/debug.qtpl:222
 			qw422016.N().S(`=`)
-//line lib/promrelabel/debug.qtpl:195
+//line lib/promrelabel/debug.qtpl:222
 			qw422016.E().Q(label.Value)
-//line lib/promrelabel/debug.qtpl:196
+//line lib/promrelabel/debug.qtpl:223
 		}
-//line lib/promrelabel/debug.qtpl:197
+//line lib/promrelabel/debug.qtpl:224
 		if i < len(labelsList)-1 {
-//line lib/promrelabel/debug.qtpl:197
+//line lib/promrelabel/debug.qtpl:224
 			qw422016.N().S(`,`)
-//line lib/promrelabel/debug.qtpl:197
+//line lib/promrelabel/debug.qtpl:224
 			qw422016.N().S(` `)
-//line lib/promrelabel/debug.qtpl:197
+//line lib/promrelabel/debug.qtpl:224
 		}
-//line lib/promrelabel/debug.qtpl:198
+//line lib/promrelabel/debug.qtpl:225
 	}
-//line lib/promrelabel/debug.qtpl:198
+//line lib/promrelabel/debug.qtpl:225
 	qw422016.N().S(`}`)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 }

-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 func writelabelsWithHighlight(qq422016 qtio422016.Writer, labels *promutil.Labels, highlight map[string]struct{}, color string) {
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	qw422016 := qt422016.AcquireWriter(qq422016)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	streamlabelsWithHighlight(qw422016, labels, highlight, color)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	qt422016.ReleaseWriter(qw422016)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 }

-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 func labelsWithHighlight(labels *promutil.Labels, highlight map[string]struct{}, color string) string {
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	qb422016 := qt422016.AcquireByteBuffer()
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	writelabelsWithHighlight(qb422016, labels, highlight, color)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	qs422016 := string(qb422016.B)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	qt422016.ReleaseByteBuffer(qb422016)
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 	return qs422016
-//line lib/promrelabel/debug.qtpl:200
+//line lib/promrelabel/debug.qtpl:227
 }

-//line lib/promrelabel/debug.qtpl:202
+//line lib/promrelabel/debug.qtpl:229
 func streammustFormatLabels(qw422016 *qt422016.Writer, s string) {
-//line lib/promrelabel/debug.qtpl:203
-	labels := promutil.MustNewLabelsFromString(s)
+//line lib/promrelabel/debug.qtpl:230
+	labels, err := promutil.NewLabelsFromString(s)

-//line lib/promrelabel/debug.qtpl:204
-	streamlabelsWithHighlight(qw422016, labels, nil, "")
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:231
+	if err != nil {
+//line lib/promrelabel/debug.qtpl:231
+		qw422016.N().S(`<span style="color: red" title="error parsing labels:`)
+//line lib/promrelabel/debug.qtpl:232
+		qw422016.E().S(err.Error())
+//line lib/promrelabel/debug.qtpl:232
+		qw422016.N().S(`">`)
+//line lib/promrelabel/debug.qtpl:232
+		qw422016.E().S("error parsing labels: " + err.Error())
+//line lib/promrelabel/debug.qtpl:232
+		qw422016.N().S(`</span>`)
+//line lib/promrelabel/debug.qtpl:233
+	} else {
+//line lib/promrelabel/debug.qtpl:234
+		streamlabelsWithHighlight(qw422016, labels, nil, "")
+//line lib/promrelabel/debug.qtpl:235
+	}
+//line lib/promrelabel/debug.qtpl:236
 }

-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 func writemustFormatLabels(qq422016 qtio422016.Writer, s string) {
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	qw422016 := qt422016.AcquireWriter(qq422016)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	streammustFormatLabels(qw422016, s)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	qt422016.ReleaseWriter(qw422016)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 }

-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 func mustFormatLabels(s string) string {
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	qb422016 := qt422016.AcquireByteBuffer()
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	writemustFormatLabels(qb422016, s)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	qs422016 := string(qb422016.B)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	qt422016.ReleaseByteBuffer(qb422016)
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 	return qs422016
-//line lib/promrelabel/debug.qtpl:205
+//line lib/promrelabel/debug.qtpl:236
 }