Add uptime to the servicez debug page (#2385)

Signed-off-by: Bogdan Drutu <bogdandrutu@gmail.com>

internal/version/version.go

@@ -18,21 +18,31 @@ import (
 	"bytes"
 	"fmt"
 	"runtime"
+	"time"
 )
 
 const (
 	buildDev     = "dev"
 	buildRelease = "release"
 )
 
-// Version variable will be replaced at link time after `make` has been run.
-var Version = "latest"
+var (
+	// Version variable will be replaced at link time after `make` has been run.
+	Version = "latest"
 
-// GitHash variable will be replaced at link time after `make` has been run.
-var GitHash = "<NOT PROPERLY GENERATED>"
+	// GitHash variable will be replaced at link time after `make` has been run.
+	GitHash = "<NOT PROPERLY GENERATED>"
 
-// BuildType should be one of (dev, release).
-var BuildType = buildDev
+	// BuildType should be one of (dev, release).
+	BuildType = buildDev
+
+	// startTime
+	startTime time.Time
+)
+
+func init() {
+	startTime = time.Now()
+}
 
 // IsDevBuild returns true if this is a development (local) build.
 func IsDevBuild() bool {
@@ -45,15 +55,20 @@ func IsReleaseBuild() bool {
 }
 
 // InfoVar is a singleton instance of the Info struct.
-var InfoVar = Info([][2]string{
+var InfoVar = Info{
 	{"Version", Version},
 	{"GitHash", GitHash},
 	{"BuildType", BuildType},
-	{"Goversion", runtime.Version()},
+	{"GoVersion", runtime.Version()},
 	{"OS", runtime.GOOS},
 	{"Architecture", runtime.GOARCH},
 	// Add other valuable build-time information here.
-})
+}
+
+// RuntimeVar returns the InfoVar plus runtime information like uptime.
+func RuntimeVar() Info {
+	return append(InfoVar, [2]string{"StartTime", startTime.String()}, [2]string{"Uptime", time.Since(startTime).String()})
+}
 
 // Info has properties about the build and runtime.
 type Info [][2]string

service/service.go

@@ -503,7 +503,7 @@ func (app *Application) handleServicezRequest(w http.ResponseWriter, r *http.Req
 		ComponentEndpoint: extensionzPath,
 		Link:              true,
 	})
-	internal.WriteHTMLPropertiesTable(w, internal.PropertiesTableData{Name: "Build And Runtime", Properties: version.InfoVar})
+	internal.WriteHTMLPropertiesTable(w, internal.PropertiesTableData{Name: "Build And Runtime", Properties: version.RuntimeVar()})
 	internal.WriteHTMLFooter(w)
 }