fix background mode and update doc

Author: jpinsonneau

cmd/flow_capture.go

@@ -24,8 +24,12 @@ var flowCmd = &cobra.Command{
 
 func runFlowCapture(_ *cobra.Command, _ []string) {
 	capture = Flow
-	go startFlowCollector()
-	createFlowDisplay()
+	if isBackground {
+		startFlowCollector()
+	} else {
+		go startFlowCollector()
+		createFlowDisplay()
+	}
 }
 
 func startFlowCollector() {

cmd/flow_display.go

@@ -460,7 +460,7 @@ func AppendFlow(genericMap config.GenericMap) {
 		return
 	}
 
-	if errAdvancedDisplay != nil {
+	if app == nil || errAdvancedDisplay != nil {
 		// simply print flow into logs
 		log.Printf("%v\n", genericMap)
 	} else {

cmd/metric_capture.go

@@ -31,8 +31,14 @@ var (
 
 func runMetricCapture(c *cobra.Command, _ []string) {
 	capture = Metric
-	go startMetricCollector(c.Context())
-	createMetricDisplay()
+
+	updateGraphs(false) // initial update of graphs to have something to display
+	if isBackground {
+		startMetricCollector(c.Context())
+	} else {
+		go startMetricCollector(c.Context())
+		createMetricDisplay()
+	}
 }
 
 func startMetricCollector(ctx context.Context) {
@@ -80,15 +86,24 @@ func startMetricCollector(ctx context.Context) {
 
 func queryGraphs(ctx context.Context, client api.Client) {
 	for index := range graphs {
-		go queryGraph(ctx, client, index)
+		if isBackground {
+			queryGraph(ctx, client, index) // keep logical order for background mode
+		} else {
+			go queryGraph(ctx, client, index)
+		}
 	}
 }
 
 func queryGraph(ctx context.Context, client api.Client, index int) {
 	query, result := queryProm(ctx, client, graphs[index].Query.PromQL)
-	if errAdvancedDisplay != nil {
+	if app == nil || errAdvancedDisplay != nil {
 		// simply print metrics into logs
-		log.Printf("%v\n", result)
+		log.Print(query.PromQL)
+		if result == nil || len(*result) == 0 {
+			log.Print("  No result")
+		} else {
+			log.Print(result.String())
+		}
 	} else {
 		appendMetrics(query, result, index)
 	}

cmd/metric_display.go

@@ -66,7 +66,6 @@ var (
 
 func createMetricDisplay() {
 	updateShowMetricCount()
-	updateGraphs(false)
 
 	app = tview.NewApplication().
 		SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {

cmd/packet_capture.go

@@ -35,8 +35,12 @@ var (
 
 func runPacketCapture(_ *cobra.Command, _ []string) {
 	capture = Packet
-	go startPacketCollector()
-	createFlowDisplay()
+	if isBackground {
+		startPacketCollector()
+	} else {
+		go startPacketCollector()
+		createFlowDisplay()
+	}
 }
 
 //nolint:cyclop

cmd/root.go

@@ -52,6 +52,7 @@ var (
 	captureEnded     = false
 	stopReceived     = false
 	useMocks         = false
+	isBackground     = false
 )
 
 // Execute executes the root command.
@@ -102,7 +103,10 @@ func onInit() {
 	printBanner()
 
 	log.Infof("Log level: %s\nOption(s): %s", logLevel, options)
-
+	if strings.Contains(options, "background") && !strings.Contains(options, "background=false") {
+		isBackground = true
+		log.Infof("Running in background mode")
+	}
 	showKernelVersion()
 
 	if useMocks {
@@ -143,7 +147,7 @@ func onLimitReached() bool {
 		if app != nil && errAdvancedDisplay == nil {
 			app.Stop()
 		}
-		if strings.Contains(options, "background=true") {
+		if isBackground {
 			out, err := exec.Command("/oc-netobserv", "stop").Output()
 			if err != nil {
 				log.Fatal(err)

docs/netobserv_cli.adoc

@@ -64,6 +64,7 @@ $ oc netobserv flows [<feature_option>] [<command_options>]
 |--enable_rtt|                enable RTT tracking                                   | false
 |--enable_udn_mapping|        enable User Defined Network mapping                   | false
 |--get-subnets|               get subnets information                               | false
+|--privileged|                force eBPF agent privileged mode                      | auto
 |--sampling|                  packets sampling interval                             | 1
 |--background|                run in background                                     | false
 |--copy|                      copy the output files locally                         | prompt
@@ -167,7 +168,10 @@ $ oc netobserv metrics [<option>]
 |--enable_rtt|                enable RTT tracking                                   | false
 |--enable_udn_mapping|        enable User Defined Network mapping                   | false
 |--get-subnets|               get subnets information                               | false
+|--privileged|                force eBPF agent privileged mode                      | auto
 |--sampling|                  packets sampling interval                             | 1
+|--background|                run in background                                     | false
+|--log-level|                 components logs                                       | info
 |--max-time|                  maximum capture time                                  | 1h
 |--action|                    filter action                                         | Accept
 |--cidr|                      filter CIDR                                           | 0.0.0.0/0

scripts/help.sh

@@ -57,6 +57,11 @@ function help {
   echo "    --drops                                                   # including drops"
   echo "    --include_list=node,namespace                             # for all metrics matching 'node' or 'namespace' keywords"
   echo
+  echo "  Capture metrics in background"
+  echo "    netobserv metrics --background \                          # Capture metrics using background mode"
+  echo "    --max-time=24h                                            # for a maximum of 24 hours"
+  echo "  Then open the URL provided by the command to visualize the netobserv-cli dashboard anytime during or after the run."
+  echo
 }
 
 # display version
@@ -90,6 +95,8 @@ function flowsAndPackets_collector_usage {
 
 # fmetrics collector options
 function metrics_collector_usage {
+  echo "  --background:                 run in background                                     (default: false)"
+  echo "  --log-level:                  components logs                                       (default: info)"
   echo "  --max-time:                   maximum capture time                                  (default: 1h)"
 }