func attach(ctx *cli.Context) {
var client comms.ExpanseClient
var err error
if ctx.Args().Present() {
client, err = comms.ClientFromEndpoint(ctx.Args().First(), codec.JSON)
} else {
cfg := comms.IpcConfig{
Endpoint: utils.IpcSocketPath(ctx),
}
client, err = comms.NewIpcClient(cfg, codec.JSON)
}
if err != nil {
utils.Fatalf("Unable to attach to gexp node - %v", err)
}
repl := newLightweightJSRE(
ctx.GlobalString(utils.JSpathFlag.Name),
client,
ctx.GlobalString(utils.DataDirFlag.Name),
true,
)
if ctx.GlobalString(utils.ExecFlag.Name) != "" {
repl.batch(ctx.GlobalString(utils.ExecFlag.Name))
} else {
repl.welcome()
repl.interactive()
}
}
// monitor starts a terminal UI based monitoring tool for the requested metrics.
func monitor(ctx *cli.Context) {
var (
client comms.ExpanseClient
err error
)
// Attach to an Expanse node over IPC or RPC
endpoint := ctx.String(monitorCommandAttachFlag.Name)
if client, err = comms.ClientFromEndpoint(endpoint, codec.JSON); err != nil {
utils.Fatalf("Unable to attach to gexp node: %v", err)
}
defer client.Close()
xeth := rpc.NewXeth(client)
// Retrieve all the available metrics and resolve the user pattens
metrics, err := retrieveMetrics(xeth)
if err != nil {
utils.Fatalf("Failed to retrieve system metrics: %v", err)
}
monitored := resolveMetrics(metrics, ctx.Args())
if len(monitored) == 0 {
list := expandMetrics(metrics, "")
sort.Strings(list)
if len(list) > 0 {
utils.Fatalf("No metrics specified.\n\nAvailable:\n - %s", strings.Join(list, "\n - "))
} else {
utils.Fatalf("No metrics collected by gexp (--%s).\n", utils.MetricsEnabledFlag.Name)
}
}
sort.Strings(monitored)
if cols := len(monitored) / ctx.Int(monitorCommandRowsFlag.Name); cols > 6 {
utils.Fatalf("Requested metrics (%d) spans more that 6 columns:\n - %s", len(monitored), strings.Join(monitored, "\n - "))
}
// Create and configure the chart UI defaults
if err := termui.Init(); err != nil {
utils.Fatalf("Unable to initialize terminal UI: %v", err)
}
defer termui.Close()
termui.UseTheme("helloworld")
rows := len(monitored)
if max := ctx.Int(monitorCommandRowsFlag.Name); rows > max {
rows = max
}
cols := (len(monitored) + rows - 1) / rows
for i := 0; i < rows; i++ {
termui.Body.AddRows(termui.NewRow())
}
// Create each individual data chart
footer := termui.NewPar("")
footer.HasBorder = true
footer.Height = 3
charts := make([]*termui.LineChart, len(monitored))
units := make([]int, len(monitored))
data := make([][]float64, len(monitored))
for i := 0; i < len(monitored); i++ {
charts[i] = createChart((termui.TermHeight() - footer.Height) / rows)
row := termui.Body.Rows[i%rows]
row.Cols = append(row.Cols, termui.NewCol(12/cols, 0, charts[i]))
}
termui.Body.AddRows(termui.NewRow(termui.NewCol(12, 0, footer)))
refreshCharts(xeth, monitored, data, units, charts, ctx, footer)
termui.Body.Align()
termui.Render(termui.Body)
// Watch for various system events, and periodically refresh the charts
refresh := time.Tick(time.Duration(ctx.Int(monitorCommandRefreshFlag.Name)) * time.Second)
for {
select {
case event := <-termui.EventCh():
if event.Type == termui.EventKey && event.Key == termui.KeyCtrlC {
return
}
if event.Type == termui.EventResize {
termui.Body.Width = termui.TermWidth()
for _, chart := range charts {
chart.Height = (termui.TermHeight() - footer.Height) / rows
}
termui.Body.Align()
termui.Render(termui.Body)
}
case <-refresh:
if refreshCharts(xeth, monitored, data, units, charts, ctx, footer) {
termui.Body.Align()
}
termui.Render(termui.Body)
}
}
}