Merge pull request #3796 from weaveworks/billing-spy-interval

billing: cope with spy-interval set longer than publish-interval

app/multitenant/billing_emitter.go

@@ -119,15 +119,34 @@ func (e *BillingEmitter) Add(ctx context.Context, rep report.Report, buf []byte)
 	return e.Collector.Add(ctx, rep, buf)
 }
 
+func commandParameter(cmd, flag string) (string, bool) {
+	i := strings.Index(cmd, flag)
+	if i != -1 {
+		// here we expect the command looks like `-foo=bar` or `-foo bar`
+		aft := strings.Fields(cmd[i+len(flag):])
+		if len(aft) > 0 && len(aft[0]) > 0 {
+			if aft[0][0] == '=' {
+				return aft[0][1:], true
+			}
+			return aft[0], true
+		}
+	}
+	return "", false
+}
+
 func intervalFromCommand(cmd string) string {
-	if strings.Contains(cmd, "scope") &&
-		strings.Contains(cmd, "probe.publish.interval") {
-		cmds := strings.SplitAfter(cmd, "probe.publish.interval")
-		aft := strings.Split(cmds[1], " ")
-		if aft[0] == "" {
-			return aft[1]
+	if strings.Contains(cmd, "scope") {
+		if publishInterval, ok := commandParameter(cmd, "probe.publish.interval"); ok {
+			// If spy interval is higher than publish interval, some reports will have no process data
+			if spyInterval, ok := commandParameter(cmd, "spy.interval"); ok {
+				pubDuration, err1 := time.ParseDuration(publishInterval)
+				spyDuration, err2 := time.ParseDuration(spyInterval)
+				if err1 == nil && err2 == nil && spyDuration > pubDuration {
+					return spyInterval
+				}
+			}
+			return publishInterval
 		}
-		return aft[0][1:]
 	}
 	return ""
 }

app/multitenant/billing_emitter_test.go

@@ -12,8 +12,12 @@ func Test_intervalFromCommand(t *testing.T) {
 		{cmd: "/home/weave/scope --mode=probe --probe-only --probe.kubernetes=true --probe.spy.interval=3s --probe.publish.interval 5s --probe.processes=false --probe.conntrack=false --probe.ebpf.connections=false --probe.docker.bridge=docker0 --probe.docker=true https://redacted@cloud.weave.works.", want: "5s", name: "space"},
 		{cmd: "/home/weave/scope --mode=probe --no-app --probe.docker=true --probe.kubernetes.role=host --weave=false --probe.publish.interval=4500ms --probe.spy.interval=2s --probe.http.listen=:4041 --probe.conntrack.buffersize=4194304 https://redacted@cloud.weave.works scope.weave.svc.cluster.local:80", want: "4500ms", name: "miliseconds"},
 		{cmd: "/home/weave/scope --mode=probe --no-app --probe.docker=true --probe.kubernetes.role=host --weave=false --probe.spy.interval=2s --probe.http.listen=:4041 --probe.conntrack.buffersize=4194304 https://redacted@cloud.weave.works scope.weave.svc.cluster.local:80", want: "", name: "notset"},
+		{cmd: "/home/weave/scope --mode=probe --probe-only --probe.kubernetes.role=host --probe.publish.interval=4500ms --probe.spy.interval=10s --probe.docker.bridge=docker0 --probe.docker=true --probe.ebpf.connections=false --probe.conntrack=false https://redacted@cloud.weave.works.", want: "10s", name: "higher-spy-interval"},
 		{cmd: "/bin/prometheus --config.file=/etc/prometheus/prometheus.yml --web.listen-address=:8080 --storage.tsdb.retention.time=2h --web.enable-lifecycle", want: "", name: "notscope"},
 		{cmd: "", want: "", name: "blank"},
+		{cmd: "/home/weave/scope --probe.publish.interval=3s", want: "3s", name: "at-end"},
+		{cmd: "/home/weave/scope --probe.publish.interval=", want: "", name: "equals-blank"},
+		{cmd: "/home/weave/scope --probe.publish.interval", want: "", name: "no-value"},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {