Add reverse_mode GET param to trigger -R passed to iperf3

.dockerignore

@@ -0,0 +1,6 @@
+.*
+Dockerfile
+LICENSE*
+NOTICE*
+README*
+iperf3_windows.go

Dockerfile

@@ -1,8 +1,18 @@
+FROM golang:alpine AS build-env
+
+# Download dependencies
+WORKDIR /go/src
+COPY go.mod go.sum ./
+RUN go mod download
+
+# Build current sources
+COPY . .
+RUN go build -o /go/bin/iperf3_exporter
+
+# Prepare runtime environment
 FROM alpine:latest
 LABEL maintainer="Edgard Castro <[email protected]>"
-
+EXPOSE 9579
 RUN apk add --no-cache iperf3
-COPY iperf3_exporter /bin/iperf3_exporter
-
+COPY --from=build-env /go/bin/iperf3_exporter /bin/
 ENTRYPOINT ["/bin/iperf3_exporter"]
-EXPOSE     9579

iperf3_exporter.go

@@ -64,10 +64,11 @@ type iperfResult struct {
 // the prometheus metrics package.
 type Exporter struct {
 	target  string
-        port	int
+	 port	int
 	period  time.Duration
 	timeout time.Duration
 	mutex   sync.RWMutex
+	reverse bool
 
 	success         *prometheus.Desc
 	sentSeconds     *prometheus.Desc
@@ -77,11 +78,12 @@ type Exporter struct {
 }
 
 // NewExporter returns an initialized Exporter.
-func NewExporter(target string, port int, period time.Duration, timeout time.Duration) *Exporter {
+func NewExporter(target string, port int, period time.Duration, timeout time.Duration, reverse bool) *Exporter {
 	return &Exporter{
 		target:          target,
                 port:            port,
 		period:          period,
+		reverse:         reverse,
 		timeout:         timeout,
 		success:         prometheus.NewDesc(prometheus.BuildFQName(namespace, "", "success"), "Was the last iperf3 probe successful.", nil, nil),
 		sentSeconds:     prometheus.NewDesc(prometheus.BuildFQName(namespace, "", "sent_seconds"), "Total seconds spent sending packets.", nil, nil),
@@ -110,7 +112,12 @@ func (e *Exporter) Collect(ch chan<- prometheus.Metric) {
 	ctx, cancel := context.WithTimeout(context.Background(), e.timeout)
 	defer cancel()
 
-	out, err := exec.CommandContext(ctx, iperfCmd, "-J", "-t", strconv.FormatFloat(e.period.Seconds(), 'f', 0, 64), "-c", e.target, "-p", strconv.Itoa(e.port)).Output()
+	var iperfArgs []string
+	iperfArgs = []string{"-J", "-t", strconv.FormatFloat(e.period.Seconds(), 'f', 0, 64), "-c", e.target, "-p", strconv.Itoa(e.port)}
+	if e.reverse{
+		iperfArgs = append(iperfArgs, "-R")
+	}
+	out, err := exec.CommandContext(ctx, iperfCmd, iperfArgs...).Output()
 	if err != nil {
 		ch <- prometheus.MustNewConstMetric(e.success, prometheus.GaugeValue, 0)
 		iperfErrors.Inc()
@@ -140,22 +147,36 @@ func handler(w http.ResponseWriter, r *http.Request) {
 		iperfErrors.Inc()
 		return
 	}
-        
+
         var targetPort int
         port := r.URL.Query().Get("port")
         if port != "" {
-                var err error 
+                var err error
                 targetPort, err = strconv.Atoi(port)
                 if err != nil {
                         http.Error(w, fmt.Sprintf("'port' parameter must be an integer: %s", err), http.StatusBadRequest)
                         iperfErrors.Inc()
                         return
                 }
-        } 
+        }
         if targetPort == 0 {
                 targetPort = 5201
         }
-
+
+	var reverseMode bool
+	reverse_mode := r.URL.Query().Get("reverse_mode")
+	if reverse_mode != "" {
+        var err error
+		reverseMode, err = strconv.ParseBool(reverse_mode)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("'reverse_mode' parameter must be true or false (boolean): %s", err), http.StatusBadRequest)
+			iperfErrors.Inc()
+			return
+		}
+	} else {
+		reverseMode = false
+	}
+
 	var runPeriod time.Duration
 	period := r.URL.Query().Get("period")
 	if period != "" {
@@ -198,7 +219,7 @@ func handler(w http.ResponseWriter, r *http.Request) {
 
 	start := time.Now()
 	registry := prometheus.NewRegistry()
-	exporter := NewExporter(target, targetPort, runPeriod, runTimeout)
+	exporter := NewExporter(target, targetPort, runPeriod, runTimeout, reverseMode)
 	registry.MustRegister(exporter)
 
 	// Delegate http serving to Prometheus client library, which will call collector.Collect.