Show loaded rules in Status dashboard.

main.go

@@ -212,6 +212,14 @@ func main() {
 	targetManager := retrieval.NewTargetManager(scrapeResults, *concurrentRetrievalAllowance)
 	targetManager.AddTargetsFromConfig(conf)
 
+	// Queue depth will need to be exposed
+	ruleManager := rules.NewRuleManager(ruleResults, conf.EvaluationInterval(), ts)
+	err = ruleManager.AddRulesFromConfig(conf)
+	if err != nil {
+		log.Fatalf("Error loading rule files: %v", err)
+	}
+	go ruleManager.Run()
+
 	flags := map[string]string{}
 
 	flag.VisitAll(func(f *flag.Flag) {
@@ -222,6 +230,7 @@ func main() {
 		PrometheusStatus: &web.PrometheusStatus{
 			BuildInfo:   BuildInfo,
 			Config:      conf.String(),
+			Rules:       ruleManager.Rules(),
 			TargetPools: targetManager.Pools(),
 			Flags:       flags,
 			Birth:       time.Now(),
@@ -321,15 +330,6 @@ func main() {
 		}
 	}()
 
-	// Queue depth will need to be exposed
-
-	ruleManager := rules.NewRuleManager(ruleResults, conf.EvaluationInterval(), ts)
-	err = ruleManager.AddRulesFromConfig(conf)
-	if err != nil {
-		log.Fatalf("Error loading rule files: %v", err)
-	}
-	go ruleManager.Run()
-
 	go func() {
 		err := webService.ServeForever()
 		if err != nil {

rules/manager.go

@@ -30,6 +30,7 @@ type Result struct {
 type RuleManager interface {
 	AddRulesFromConfig(config config.Config) error
 	Run()
+	Rules() []Rule
 }
 
 type ruleManager struct {
@@ -117,3 +118,12 @@ func (m *ruleManager) AddRulesFromConfig(config config.Config) error {
 	}
 	return nil
 }
+
+func (m *ruleManager) Rules() []Rule {
+	m.Lock()
+	defer m.Unlock()
+
+	rules := make([]Rule, len(m.rules))
+	copy(rules, m.rules)
+	return rules
+}

web/status.go

@@ -15,6 +15,7 @@ package web
 
 import (
 	"github.com/prometheus/prometheus/retrieval"
+	"github.com/prometheus/prometheus/rules"
 	"github.com/prometheus/prometheus/storage/metric"
 	"net/http"
 	"sync"
@@ -26,7 +27,7 @@ type PrometheusStatus struct {
 	Config      string
 	Curation    metric.CurationState
 	Flags       map[string]string
-	Rules       string
+	Rules       []rules.Rule
 	TargetPools map[string]*retrieval.TargetPool
 
 	Birth time.Time

web/templates/status.html

@@ -35,7 +35,7 @@
 
     <h2>Rules</h2>
     <div class="grouping_box">
-{{.Rules}}
+    <pre>{{range .Rules}}{{.String}}{{end}}</pre>
     </div>
 
     <h2>Targets</h2>