refactor: enhancement of logging, config and metrics

internal/checkConfig.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"github.com/jkaninda/goma-gateway/util"
 	"gopkg.in/yaml.v3"
-	"log"
 	"os"
 )
 
@@ -46,21 +45,21 @@ func CheckConfig(fileName string) error {
 	}
 	for index, route := range gateway.gateway.Routes {
 		if len(route.Name) == 0 {
-			log.Printf("Warning: route name is empty, index: [%d]", index)
+			fmt.Printf("Warning: route name is empty, index: [%d]", index)
 		}
 		if route.Destination == "" && len(route.Backends) == 0 {
-			log.Printf("Error: no destination or backends specified for route: %s | index: [%d] \n", route.Name, index)
+			fmt.Printf("Error: no destination or backends specified for route: %s | index: [%d] \n", route.Name, index)
 		}
 	}
 
 	//Check middleware
 	for index, mid := range c.Middlewares {
 		if util.HasWhitespace(mid.Name) {
-			log.Printf("Warning: Middleware contains whitespace: %s | index: [%d], please remove whitespace characters\n", mid.Name, index)
+			fmt.Printf("Warning: Middleware contains whitespace: %s | index: [%d], please remove whitespace characters\n", mid.Name, index)
 		}
 	}
 
-	log.Printf("Routes count=%d Middlewares count=%d\n", len(gateway.gateway.Routes), len(gateway.middlewares))
+	fmt.Printf("Routes count=%d Middlewares count=%d\n", len(gateway.gateway.Routes), len(gateway.middlewares))
 
 	return nil
 

internal/config.go

@@ -20,7 +20,6 @@ import (
 	"github.com/jkaninda/goma-gateway/internal/middleware"
 	"github.com/jkaninda/goma-gateway/pkg/logger"
 	"github.com/jkaninda/goma-gateway/util"
-	"github.com/spf13/cobra"
 	"golang.org/x/oauth2"
 	"golang.org/x/oauth2/amazon"
 	"golang.org/x/oauth2/facebook"
@@ -83,7 +82,11 @@ func (GatewayServer) Config(configFile string) (*GatewayServer, error) {
 			return nil, err
 		}
 	}
-	initConfig(ConfigFile)
+	err := initConfig(ConfigFile)
+	if err != nil {
+		return nil, err
+	}
+	logger.Info("Generating new configuration file...done")
 	logger.Info("Server configuration file is available at %s", ConfigFile)
 	util.SetEnv("GOMA_CONFIG_FILE", ConfigFile)
 	buf, err := os.ReadFile(ConfigFile)
@@ -115,18 +118,13 @@ func GetConfigPaths() string {
 }
 
 // InitConfig initializes configs
-func InitConfig(cmd *cobra.Command) {
-	configFile, _ := cmd.Flags().GetString("output")
-	if configFile == "" {
-		configFile = GetConfigPaths()
-	}
-	initConfig(configFile)
-	return
+func InitConfig(configFile string) error {
+	return initConfig(configFile)
 
 }
 
 // initConfig initializes configs
-func initConfig(configFile string) {
+func initConfig(configFile string) error {
 	if configFile == "" {
 		configFile = GetConfigPaths()
 	}
@@ -292,13 +290,13 @@ func initConfig(configFile string) {
 	}
 	yamlData, err := yaml.Marshal(&conf)
 	if err != nil {
-		logger.Fatal("Error serializing configuration %v", err.Error())
+		return fmt.Errorf("serializing configuration %v\n", err.Error())
 	}
 	err = os.WriteFile(configFile, yamlData, 0644)
 	if err != nil {
-		logger.Fatal("Unable to write config file %s", err)
+		return fmt.Errorf("unable to write config file %s\n", err)
 	}
-	logger.Info("Configuration file has been initialized successfully")
+	return nil
 }
 func (Gateway) Setup(conf string) *Gateway {
 	if util.FileExists(conf) {

internal/helpers.go

@@ -27,7 +27,12 @@ func printRoute(routes []Route) {
 	t := table.NewWriter()
 	t.AppendHeader(table.Row{"Name", "Route", "Rewrite", "Destination"})
 	for _, route := range routes {
-		t.AppendRow(table.Row{route.Name, route.Path, route.Rewrite, route.Destination})
+		if len(route.Backends) > 0 {
+			t.AppendRow(table.Row{route.Name, route.Path, route.Rewrite, fmt.Sprintf("backends: [%d]", len(route.Backends))})
+
+		} else {
+			t.AppendRow(table.Row{route.Name, route.Path, route.Rewrite, route.Destination})
+		}
 	}
 	fmt.Println(t.Render())
 }

internal/prometheus.go

@@ -35,7 +35,7 @@ var totalRequests = prometheus.NewCounterVec(
 		Name: "http_requests_total",
 		Help: "Number of get requests.",
 	},
-	[]string{"path"},
+	[]string{"name", "path"},
 )
 
 var responseStatus = prometheus.NewCounterVec(
@@ -49,16 +49,19 @@ var responseStatus = prometheus.NewCounterVec(
 var httpDuration = promauto.NewHistogramVec(prometheus.HistogramOpts{
 	Name: "http_response_time_seconds",
 	Help: "Duration of HTTP requests.",
-}, []string{"path"})
+}, []string{"name", "path"})
 
-func prometheusMiddleware(next http.Handler) http.Handler {
+func (pr PrometheusRoute) prometheusMiddleware(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		route := mux.CurrentRoute(r)
-		path, _ := route.GetPathTemplate()
-		timer := prometheus.NewTimer(httpDuration.WithLabelValues(path))
+		path := pr.path
+		if len(path) == 0 {
+			route := mux.CurrentRoute(r)
+			path, _ = route.GetPathTemplate()
+		}
+		timer := prometheus.NewTimer(httpDuration.WithLabelValues(pr.name, path))
 
 		responseStatus.WithLabelValues(strconv.Itoa(http.StatusOK)).Inc()
-		totalRequests.WithLabelValues(path).Inc()
+		totalRequests.WithLabelValues(pr.name, path).Inc()
 
 		timer.ObserveDuration()
 		next.ServeHTTP(w, r)

internal/route.go

@@ -43,9 +43,7 @@ func (gatewayServer GatewayServer) Initialize() *mux.Router {
 	if gateway.EnableMetrics {
 		// Prometheus endpoint
 		r.Path("/metrics").Handler(promhttp.Handler())
-		r.Use(prometheusMiddleware)
 	}
-
 	// Routes health check
 	if !gateway.DisableHealthCheckStatus {
 		r.HandleFunc("/healthz", heath.HealthCheckHandler).Methods("GET")
@@ -238,7 +236,14 @@ func (gatewayServer GatewayServer) Initialize() *mux.Router {
 			} else {
 				router.PathPrefix("").Handler(proxyRoute.ProxyHandler())
 			}
-
+			if gateway.EnableMetrics {
+				pr := PrometheusRoute{
+					name: route.Name,
+					path: route.Path,
+				}
+				// Prometheus endpoint
+				router.Use(pr.prometheusMiddleware)
+			}
 		} else {
 			logger.Error("Error, path is empty in route %s", route.Name)
 			logger.Error("Route path ignored: %s", route.Path)