publish v12.2.0-alpha6

middleware/monitor/monitor.go

@@ -0,0 +1,105 @@
+package monitor
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/kataras/iris/v12/context"
+
+	"github.com/shirou/gopsutil/v3/process"
+)
+
+func init() {
+	context.SetHandlerName("iris/middleware/monitor.*", "iris.monitor")
+}
+
+// Options holds the optional fields for the Monitor structure.
+type Options struct {
+	// Optional process id, defaults to the current one.
+	PID int32 `json:"pid" yaml:"PID"`
+
+	RefreshInterval     time.Duration `json:"refresh_interval" yaml:"RefreshInterval"`
+	ViewRefreshInterval time.Duration `json:"view_refresh_interval" yaml:"ViewRefreshInterval"`
+	// If more than zero enables line animation. Defaults to zero.
+	ViewAnimationInterval time.Duration `json:"view_animation_interval" yaml:"ViewAnimationInterval"`
+	// The title of the monitor HTML document.
+	ViewTitle string `json:"view_title" yaml:"ViewTitle"`
+}
+
+// Monitor tracks and renders the server's process and operating system statistics.
+//
+// Look its `Stats` and `View` methods.
+// Initialize with the `New` package-level function.
+type Monitor struct {
+	opts   Options
+	Holder *StatsHolder
+
+	viewBody []byte
+}
+
+// New returns a new Monitor.
+// Metrics stored through expvar standard package:
+// - pid_cpu
+// - pid_ram
+// - pid_conns
+// - os_cpu
+// - os_ram
+// - os_total_ram
+// - os_load_avg
+// - os_conns
+//
+// Check https://github.com/iris-contrib/middleware/tree/master/expmetric
+// which can be integrated with datadog or other platforms.
+func New(opts Options) *Monitor {
+	if opts.PID == 0 {
+		opts.PID = int32(os.Getpid())
+	}
+
+	if opts.RefreshInterval <= 0 {
+		opts.RefreshInterval = 2 * opts.RefreshInterval
+	}
+
+	if opts.ViewRefreshInterval <= 0 {
+		opts.ViewRefreshInterval = opts.RefreshInterval
+	}
+
+	viewRefreshIntervalBytes := []byte(fmt.Sprintf("%d", opts.ViewRefreshInterval.Milliseconds()))
+	viewBody := bytes.Replace(defaultViewBody, viewRefreshIntervalTmplVar, viewRefreshIntervalBytes, 1)
+	viewAnimationIntervalBytes := []byte(fmt.Sprintf("%d", opts.ViewAnimationInterval.Milliseconds()))
+	viewBody = bytes.Replace(viewBody, viewAnimationIntervalTmplVar, viewAnimationIntervalBytes, 2)
+	viewTitleBytes := []byte(opts.ViewTitle)
+	viewBody = bytes.Replace(viewBody, viewTitleTmplVar, viewTitleBytes, 2)
+	proc, err := process.NewProcess(opts.PID)
+	if err != nil {
+		panic(err)
+	}
+
+	sh := startNewStatsHolder(proc, opts.RefreshInterval)
+	m := &Monitor{
+		opts:     opts,
+		Holder:   sh,
+		viewBody: viewBody,
+	}
+
+	return m
+}
+
+// Stop terminates the retrieve stats loop for
+// the process and the operating system statistics.
+// No other monitor instance should be initialized after the first Stop call.
+func (m *Monitor) Stop() {
+	m.Holder.Stop()
+}
+
+// Stats sends the stats as json.
+func (m *Monitor) Stats(ctx *context.Context) {
+	ctx.JSON(m.Holder.GetStats())
+}
+
+// View renders a default view for the stats.
+func (m *Monitor) View(ctx *context.Context) {
+	ctx.ContentType("text/html")
+	ctx.Write(m.viewBody)
+}