README

Makefile

@@ -1,11 +1,10 @@
-#GOFLAGS=""
 LDFLAGS=-ldflags "-s -w"
 BINARY=metrorama
 
 .DEFAULT_GOAL: $(BINARY)
 
 $(BINARY): clean
-	go build ${GOFLAGS} ${LDFLAGS} -o ${BINARY}
+	GOOS=linux GOARCH=amd64 CGO_ENABLED=0 go build ${GOFLAGS} ${LDFLAGS} -o ${BINARY}
 
 install:
 	go install ${GOFLAGS} ${LDFLAGS} -o ${BINARY}

README.org

@@ -1,4 +1,4 @@
-* Install
+* Install dependencies
 
 - =make deps=
 
@@ -10,6 +10,13 @@
 
 - =make run=
 
+* Build container image (must have =buildah= installed)
+
+- =buildah unshare=
+- =./build.sh=
+
+*NOTE*: Not sure about "system metrics" when run in container...
+
 * Usage
 
 Use =metrorama -h= to see a list of flags and options.

build.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+# Remember to run buildah unshare before launching this
+# Build container
+echo "Start creating first stage "
+buildctrl=$(buildah from golang:1.15.2)
+buildmnt=$(buildah mount $buildctrl)
+
+buildah copy $buildctrl *.go .
+buildah copy $buildctrl Makefile .
+buildah run $buildctrl make deps
+buildah run $buildctrl make
+
+# Runtime container
+echo "Start creating second stage"
+buildctrl2=$(buildah from alpine:latest)
+buildmnt2=$(buildah mount $builctrl2)
+
+buildah copy $buildctrl2 $buildmnt/go/metrorama 
+buildah config --cmd ./metrorama $buildctrl2
+buildah config --port 8080 $buildctrl2
+buildah unmount $buildctrl
+buildah unmount $buildctrl2
+buildah commit $buildctrl2 metrorama:latest
+buildah rm $buildctrl $buildctrl2

main.go

@@ -86,7 +86,7 @@ func (t *Test) collectData() {
 	return // really needed?
 }
 
-func (t *Test) startTest(w http.ResponseWriter, req *http.Request) {
+func (t *Test) Start(w http.ResponseWriter, req *http.Request) {
 	// Check if another collectData is running (better: check sync.Mutex)
 	if t.Status == "ONGOING" {
 		http.Error(w, "Another test is currently ongoing, stop or try again later", 409) //better error code
@@ -144,7 +144,7 @@ func (t *Test) startTest(w http.ResponseWriter, req *http.Request) {
 	go t.collectData()
 }
 
-func (t *Test) stopTest(w http.ResponseWriter, req *http.Request) {
+func (t *Test) Stop(w http.ResponseWriter, req *http.Request) {
 	if t.Status != "ONGOING" {
 		e := fmt.Sprintf("Cannot stop test in %s status: try start first", t.Status)
 		http.Error(w, e, 400)
@@ -157,18 +157,54 @@ func (t *Test) stopTest(w http.ResponseWriter, req *http.Request) {
 	fmt.Fprintf(w, "%v\n", t.Result)
 }
 
-func (t *Test) testStatus(w http.ResponseWriter, req *http.Request) {
+func (t *Test) getStatus(w http.ResponseWriter, req *http.Request) {
+	qStream := req.URL.Query().Get("stream")
 	qFormat := req.URL.Query().Get("format")
+
+	flusher, ok := w.(http.Flusher)
+	if !ok {
+		if qStream == "true" {
+			log.Printf("Http server does not support flusher\n")
+			http.Error(w, "Server does not support flusher",
+				http.StatusInternalServerError)
+			return
+		}
+	}
+
+	if qStream == "true" {
+		w.Header().Set("Content-Type", "text/event-stream")
+		w.Header().Set("Cache-Control", "no-cache")
+		w.Header().Set("Connection", "keep-alive")
+	}
+
 	if qFormat == "json" {
+		for {
 			b, err := json.Marshal(t.Result)
 			if err != nil {
 				log.Printf("Cannot marshal json: %s\n", err)
 				http.Error(w, err.Error(), 500)
 				return
 			}
+
 			fmt.Fprintf(w, "%s\n", b)
+
+			if qStream == "true" {
+				time.Sleep(time.Duration(t.Rate) * time.Millisecond)
+				flusher.Flush()
 			} else {
-		fmt.Fprintf(w, "%v\n", t.Result)
+				return
+			}
+		}
+	} else {
+		for {
+			fmt.Fprintf(w, "%+ v\n", t.Result)
+			if qStream == "true" {
+				time.Sleep(time.Duration(t.Rate) * time.Millisecond)
+				flusher.Flush()
+			} else {
+				return
+			}
+		}
 		fmt.Fprintf(w, "Test %s, status: %s\n", t.Name, t.Status)
 	}
 }
@@ -193,9 +229,9 @@ func main() {
 	t := newTest()
 	log.Printf("%+v\n", t)
 
-	http.HandleFunc("/start", t.startTest)
+	http.HandleFunc("/start", t.Start)
-	http.HandleFunc("/status", t.testStatus)
+	http.HandleFunc("/status", t.getStatus)
-	http.HandleFunc("/stop", t.stopTest)
+	http.HandleFunc("/stop", t.Stop)
 
 	log.Printf("Listening on %s\n", *listen)
 	log.Fatal(http.ListenAndServe(*listen, nil))