Merge branch 'improvement/list-handled-jobs' into 'master'

Add '/debug/jobs/list' endpoint that lists all handled jobs

See merge request !564

commands/builds_helper.go

 package commands
 
 import (
+	"fmt"
+	"net/http"
+	"strings"
 	"sync"
 
 	"gitlab.com/gitlab-org/gitlab-ci-multi-runner/common"
@@ -194,3 +197,19 @@ func (b *buildsHelper) Collect(ch chan<- prometheus.Metric) {
 		)
 	}
 }
+
+func (b *buildsHelper) ListJobsHandler(w http.ResponseWriter, r *http.Request) {
+	w.Header().Add("Content-Type", "text/plain")
+
+	var jobs []string
+	for _, job := range b.builds {
+		jobDescription := fmt.Sprintf(
+			"id=%d url=%s state=%s stage=%s executor_stage=%s",
+			job.ID, job.RepoCleanURL(),
+			job.CurrentState, job.CurrentStage, job.CurrentExecutorStage(),
+		)
+		jobs = append(jobs, jobDescription)
+	}
+
+	w.Write([]byte(strings.Join(jobs, "\n")))
+}

commands/multi.go

@@ -342,14 +342,7 @@ func (mr *RunCommand) runWait() {
 	mr.stopSignal = <-mr.stopSignals
 }
 
-func (mr *RunCommand) serveMetrics() error {
-	// We separate out the listener creation here so that we can return an error if
-	// the provided address is invalid or there is some other listener error.
-	listener, err := net.Listen("tcp", mr.metricsServerAddress())
-	if err != nil {
-		return err
-	}
-
+func (mr *RunCommand) serveMetrics() {
 	registry := prometheus.NewRegistry()
 	// Metrics about the runner's business logic.
 	registry.MustRegister(&mr.buildsHelper)
@@ -370,22 +363,37 @@ func (mr *RunCommand) serveMetrics() error {
 	}
 
 	http.Handle("/metrics", promhttp.HandlerFor(registry, promhttp.HandlerOpts{}))
+}
+
+func (mr *RunCommand) serveDebugData() {
+	http.Handle("/debug/jobs/list", http.HandlerFunc(mr.buildsHelper.ListJobsHandler))
+}
+
+func (mr *RunCommand) setupMetricsAndDebugServer() {
+	if mr.metricsServerAddress() == "" {
+		log.Infoln("Metrics server disabled")
+		return
+	}
+
+	// We separate out the listener creation here so that we can return an error if
+	// the provided address is invalid or there is some other listener error.
+	listener, err := net.Listen("tcp", mr.metricsServerAddress())
+	if err != nil {
+		log.Fatalln(err)
+	}
+
 	go func() {
 		log.Fatalln(http.Serve(listener, nil))
 	}()
 
-	return nil
+	mr.serveMetrics()
+	mr.serveDebugData()
+
+	log.Infoln("Metrics server listening at", mr.metricsServerAddress())
 }
 
 func (mr *RunCommand) Run() {
-	if mr.metricsServerAddress() != "" {
-		if err := mr.serveMetrics(); err != nil {
-			log.Fatalln(err)
-		}
-		log.Infoln("Metrics server listening at", mr.metricsServerAddress())
-	} else {
-		log.Infoln("Metrics server disabled")
-	}
+	mr.setupMetricsAndDebugServer()
 
 	runners := make(chan *common.RunnerConfig)
 	go mr.feedRunners(runners)