Merge pull request #169 from kaleido-io/monitoring-health-route

Add Livez route to monitoring server

pkg/ffapi/apiserver.go

@@ -22,6 +22,7 @@ import (
 	"io"
 	"net"
 	"net/http"
+	"strings"
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -63,6 +64,7 @@ type apiServer[T any] struct {
 	handleYAML                bool
 	monitoringEnabled         bool
 	metricsPath               string
+	livenessPath              string
 	monitoringPublicURL       string
 	mux                       *mux.Router
 
@@ -103,6 +105,7 @@ func NewAPIServer[T any](ctx context.Context, options APIServerOptions[T]) APISe
 		requestMaxTimeout:         options.APIConfig.GetDuration(ConfAPIRequestMaxTimeout),
 		monitoringEnabled:         options.MonitoringConfig.GetBool(ConfMonitoringServerEnabled),
 		metricsPath:               options.MonitoringConfig.GetString(ConfMonitoringServerMetricsPath),
+		livenessPath:              options.MonitoringConfig.GetString(ConfMonitoringServerLivenessPath),
 		alwaysPaginate:            options.APIConfig.GetBool(ConfAPIAlwaysPaginate),
 		handleYAML:                options.HandleYAML,
 		apiDynamicPublicURLHeader: options.APIConfig.GetString(ConfAPIDynamicPublicURLHeader),
@@ -301,6 +304,11 @@ func (as *apiServer[T]) notFoundHandler(res http.ResponseWriter, req *http.Reque
 	return 404, i18n.NewError(req.Context(), i18n.Msg404NotFound)
 }
 
+func (as *apiServer[T]) emptyJSONHandler(res http.ResponseWriter, _ *http.Request) (status int, err error) {
+	res.Header().Add("Content-Type", "application/json")
+	return 200, nil
+}
+
 func (as *apiServer[T]) createMonitoringMuxRouter(ctx context.Context) *mux.Router {
 	r := mux.NewRouter().UseEncodedPath()
 	hf := as.handlerFactory() // TODO separate factory for monitoring ??
@@ -310,9 +318,14 @@ func (as *apiServer[T]) createMonitoringMuxRouter(ctx context.Context) *mux.Rout
 		panic(err)
 	}
 	r.Path(as.metricsPath).Handler(h)
+	r.HandleFunc(as.livenessPath, hf.APIWrapper(as.emptyJSONHandler))
 
 	for _, route := range as.MonitoringRoutes {
-		r.HandleFunc(route.Path, as.routeHandler(hf, route)).Methods(route.Method)
+		path := route.Path
+		if !strings.HasPrefix(route.Path, "/") {
+			path = fmt.Sprintf("/%s", route.Path)
+		}
+		r.HandleFunc(path, as.routeHandler(hf, route)).Methods(route.Method)
 	}
 
 	r.NotFoundHandler = hf.APIWrapper(as.notFoundHandler)

pkg/ffapi/apiserver_config.go

@@ -22,8 +22,9 @@ import (
 )
 
 var (
-	ConfMonitoringServerEnabled     = "enabled"
-	ConfMonitoringServerMetricsPath = "metricsPath"
+	ConfMonitoringServerEnabled      = "enabled"
+	ConfMonitoringServerMetricsPath  = "metricsPath"
+	ConfMonitoringServerLivenessPath = "livenessPath"
 
 	ConfAPIDefaultFilterLimit     = "defaultFilterLimit"
 	ConfAPIMaxFilterLimit         = "maxFilterLimit"
@@ -49,4 +50,5 @@ func InitAPIServerConfig(apiConfig, monitoringConfig, corsConfig config.Section)
 	httpserver.InitHTTPConfig(monitoringConfig, 6000)
 	monitoringConfig.AddKnownKey(ConfMonitoringServerEnabled, true)
 	monitoringConfig.AddKnownKey(ConfMonitoringServerMetricsPath, "/metrics")
+	monitoringConfig.AddKnownKey(ConfMonitoringServerLivenessPath, "/livez")
 }