1 files changed, 309 insertions, 0 deletions
diff --git a/cmd/geth/monitorcmd.go b/cmd/geth/monitorcmd.go
new file mode 100644
index 000000000..bb9c61a00
--- /dev/null
+++ b/cmd/geth/monitorcmd.go
@@ -0,0 +1,309 @@
+package main
+
+import (
+	"fmt"
+	"math"
+	"reflect"
+	"runtime"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/codegangsta/cli"
+	"github.com/ethereum/go-ethereum/cmd/utils"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/ethereum/go-ethereum/rpc/codec"
+	"github.com/ethereum/go-ethereum/rpc/comms"
+	"github.com/gizak/termui"
+)
+
+var (
+	monitorCommandAttachFlag = cli.StringFlag{
+		Name:  "attach",
+		Value: "ipc:" + common.DefaultIpcPath(),
+		Usage: "API endpoint to attach to",
+	}
+	monitorCommandRowsFlag = cli.IntFlag{
+		Name:  "rows",
+		Value: 5,
+		Usage: "Maximum rows in the chart grid",
+	}
+	monitorCommandRefreshFlag = cli.IntFlag{
+		Name:  "refresh",
+		Value: 3,
+		Usage: "Refresh interval in seconds",
+	}
+	monitorCommand = cli.Command{
+		Action: monitor,
+		Name:   "monitor",
+		Usage:  `Geth Monitor: node metrics monitoring and visualization`,
+		Description: `
+The Geth monitor is a tool to collect and visualize various internal metrics
+gathered by the node, supporting different chart types as well as the capacity
+to display multiple metrics simultaneously.
+`,
+		Flags: []cli.Flag{
+			monitorCommandAttachFlag,
+			monitorCommandRowsFlag,
+			monitorCommandRefreshFlag,
+		},
+	}
+)
+
+// monitor starts a terminal UI based monitoring tool for the requested metrics.
+func monitor(ctx *cli.Context) {
+	var (
+		client comms.EthereumClient
+		err    error
+	)
+	// Attach to an Ethereum 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 geth 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)
+		utils.Fatalf("No metrics specified.\n\nAvailable:\n - %s", strings.Join(list, "\n - "))
+	}
+	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))
+	data := make([][]float64, len(monitored))
+	for i := 0; i < len(data); i++ {
+		data[i] = make([]float64, 512)
+	}
+	for i, metric := range monitored {
+		charts[i] = termui.NewLineChart()
+		if runtime.GOOS == "windows" {
+			charts[i].Mode = "dot"
+		}
+		charts[i].Data = make([]float64, 512)
+		charts[i].DataLabels = []string{""}
+		charts[i].Height = (termui.TermHeight() - footer.Height) / rows
+		charts[i].AxesColor = termui.ColorWhite
+		charts[i].PaddingBottom = -2
+
+		charts[i].Border.Label = metric
+		charts[i].Border.LabelFgColor = charts[i].Border.FgColor | termui.AttrBold
+		charts[i].Border.FgColor = charts[i].Border.BgColor
+
+		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)))
+	termui.Body.Align()
+	termui.Render(termui.Body)
+
+	refreshCharts(xeth, monitored, data, charts, ctx, footer)
+	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:
+			refreshCharts(xeth, monitored, data, charts, ctx, footer)
+			termui.Render(termui.Body)
+		}
+	}
+}
+
+// retrieveMetrics contacts the attached geth node and retrieves the entire set
+// of collected system metrics.
+func retrieveMetrics(xeth *rpc.Xeth) (map[string]interface{}, error) {
+	return xeth.Call("debug_metrics", []interface{}{true})
+}
+
+// resolveMetrics takes a list of input metric patterns, and resolves each to one
+// or more canonical metric names.
+func resolveMetrics(metrics map[string]interface{}, patterns []string) []string {
+	res := []string{}
+	for _, pattern := range patterns {
+		res = append(res, resolveMetric(metrics, pattern, "")...)
+	}
+	return res
+}
+
+// resolveMetrics takes a single of input metric pattern, and resolves it to one
+// or more canonical metric names.
+func resolveMetric(metrics map[string]interface{}, pattern string, path string) []string {
+	results := []string{}
+
+	// If a nested metric was requested, recurse optionally branching (via comma)
+	parts := strings.SplitN(pattern, "/", 2)
+	if len(parts) > 1 {
+		for _, variation := range strings.Split(parts[0], ",") {
+			if submetrics, ok := metrics[variation].(map[string]interface{}); !ok {
+				utils.Fatalf("Failed to retrieve system metrics: %s", path+variation)
+				return nil
+			} else {
+				results = append(results, resolveMetric(submetrics, parts[1], path+variation+"/")...)
+			}
+		}
+		return results
+	}
+	// Depending what the last link is, return or expand
+	for _, variation := range strings.Split(pattern, ",") {
+		switch metric := metrics[variation].(type) {
+		case float64:
+			// Final metric value found, return as singleton
+			results = append(results, path+variation)
+
+		case map[string]interface{}:
+			results = append(results, expandMetrics(metric, path+variation+"/")...)
+
+		default:
+			utils.Fatalf("Metric pattern resolved to unexpected type: %v", reflect.TypeOf(metric))
+			return nil
+		}
+	}
+	return results
+}
+
+// expandMetrics expands the entire tree of metrics into a flat list of paths.
+func expandMetrics(metrics map[string]interface{}, path string) []string {
+	// Iterate over all fields and expand individually
+	list := []string{}
+	for name, metric := range metrics {
+		switch metric := metric.(type) {
+		case float64:
+			// Final metric value found, append to list
+			list = append(list, path+name)
+
+		case map[string]interface{}:
+			// Tree of metrics found, expand recursively
+			list = append(list, expandMetrics(metric, path+name+"/")...)
+
+		default:
+			utils.Fatalf("Metric pattern %s resolved to unexpected type: %v", path+name, reflect.TypeOf(metric))
+			return nil
+		}
+	}
+	return list
+}
+
+// fetchMetric iterates over the metrics map and retrieves a specific one.
+func fetchMetric(metrics map[string]interface{}, metric string) float64 {
+	parts, found := strings.Split(metric, "/"), true
+	for _, part := range parts[:len(parts)-1] {
+		metrics, found = metrics[part].(map[string]interface{})
+		if !found {
+			return 0
+		}
+	}
+	if v, ok := metrics[parts[len(parts)-1]].(float64); ok {
+		return v
+	}
+	return 0
+}
+
+// refreshCharts retrieves a next batch of metrics, and inserts all the new
+// values into the active datasets and charts
+func refreshCharts(xeth *rpc.Xeth, metrics []string, data [][]float64, charts []*termui.LineChart, ctx *cli.Context, footer *termui.Par) {
+	values, err := retrieveMetrics(xeth)
+	for i, metric := range metrics {
+		data[i] = append([]float64{fetchMetric(values, metric)}, data[i][:len(data[i])-1]...)
+		updateChart(metric, data[i], charts[i], err)
+	}
+	updateFooter(ctx, err, footer)
+}
+
+// updateChart inserts a dataset into a line chart, scaling appropriately as to
+// not display weird labels, also updating the chart label accordingly.
+func updateChart(metric string, data []float64, chart *termui.LineChart, err error) {
+	dataUnits := []string{"", "K", "M", "G", "T", "E"}
+	timeUnits := []string{"ns", "µs", "ms", "s", "ks", "ms"}
+	colors := []termui.Attribute{termui.ColorBlue, termui.ColorCyan, termui.ColorGreen, termui.ColorYellow, termui.ColorRed, termui.ColorRed}
+
+	// Extract only part of the data that's actually visible
+	data = data[:chart.Width*2]
+
+	// Find the maximum value and scale under 1K
+	high := data[0]
+	for _, value := range data[1:] {
+		high = math.Max(high, value)
+	}
+	unit, scale := 0, 1.0
+	for high >= 1000 {
+		high, unit, scale = high/1000, unit+1, scale*1000
+	}
+	// Update the chart's data points with the scaled values
+	for i, value := range data {
+		chart.Data[i] = value / scale
+	}
+	// Update the chart's label with the scale units
+	chart.Border.Label = metric
+
+	units := dataUnits
+	if strings.Contains(metric, "/Percentiles/") || strings.Contains(metric, "/pauses/") {
+		units = timeUnits
+	}
+	if len(units[unit]) > 0 {
+		chart.Border.Label += " [" + units[unit] + "]"
+	}
+	chart.LineColor = colors[unit] | termui.AttrBold
+	if err != nil {
+		chart.LineColor = termui.ColorRed | termui.AttrBold
+	}
+}
+
+// updateFooter updates the footer contents based on any encountered errors.
+func updateFooter(ctx *cli.Context, err error, footer *termui.Par) {
+	// Generate the basic footer
+	refresh := time.Duration(ctx.Int(monitorCommandRefreshFlag.Name)) * time.Second
+	footer.Text = fmt.Sprintf("Press Ctrl+C to quit. Refresh interval: %v.", refresh)
+	footer.TextFgColor = termui.Theme().ParTextFg | termui.AttrBold
+
+	// Append any encountered errors
+	if err != nil {
+		footer.Text = fmt.Sprintf("Error: %v.", err)
+		footer.TextFgColor = termui.ColorRed | termui.AttrBold
+	}
+}