refactor: enhancement of logging, config and metrics

cmd/config/check.go

@@ -18,9 +18,10 @@
 package config
 
 import (
+	"fmt"
 	pkg "github.com/jkaninda/goma-gateway/internal"
 	"github.com/spf13/cobra"
-	"log"
+	"os"
 )
 
 var CheckConfigCmd = &cobra.Command{
@@ -29,13 +30,15 @@ var CheckConfigCmd = &cobra.Command{
 	Run: func(cmd *cobra.Command, args []string) {
 		configFile, _ := cmd.Flags().GetString("config")
 		if configFile == "" {
-			log.Fatalln("no config file specified")
+			fmt.Println("no config file specified")
+			os.Exit(1)
 		}
 		err := pkg.CheckConfig(configFile)
 		if err != nil {
-			log.Fatalf(" Error checking config file: %s\n", err)
+			fmt.Printf(" Error checking config file: %s\n", err)
+			os.Exit(1)
 		}
-		log.Println("Goma Gateway configuration file checked successfully")
+		fmt.Println("Goma Gateway configuration file checked successfully")
 
 	},
 }

cmd/config/config.go

@@ -17,8 +17,9 @@ limitations under the License.
 package config
 
 import (
+	"fmt"
 	"github.com/spf13/cobra"
-	"log"
+	"os"
 )
 
 var Cmd = &cobra.Command{
@@ -28,8 +29,8 @@ var Cmd = &cobra.Command{
 		if len(args) == 0 {
 			return
 		} else {
-			log.Fatalf("Config accepts no argument %q", args)
+			fmt.Printf("config accepts no argument %q\n", args)
-
+			os.Exit(1)
 		}
 
 	},

cmd/config/init.go

@@ -16,9 +16,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 import (
+	"fmt"
 	"github.com/jkaninda/goma-gateway/internal"
-	"github.com/jkaninda/goma-gateway/pkg/logger"
 	"github.com/spf13/cobra"
+	"os"
 )
 
 var InitConfigCmd = &cobra.Command{
@@ -26,14 +27,34 @@ var InitConfigCmd = &cobra.Command{
 	Short: "Initialize Goma Gateway configuration file",
 	Run: func(cmd *cobra.Command, args []string) {
 		if len(args) == 0 {
-			pkg.InitConfig(cmd)
+			force, _ := cmd.Flags().GetBool("force")
+			configFile, _ := cmd.Flags().GetString("output")
+			if configFile == "" {
+				fmt.Println("Error: no config file specified")
+				os.Exit(1)
+			}
+			// Check if the config file exists
+			if _, err := os.Stat(configFile); !os.IsNotExist(err) {
+				if !force {
+					fmt.Printf("%s config file already exists, use -f to overwrite\n", configFile)
+					os.Exit(1)
+				}
+			}
+			err := pkg.InitConfig(configFile)
+			if err != nil {
+				fmt.Println(err)
+				os.Exit(1)
+			}
+			fmt.Println("configuration file has been initialized successfully")
 		} else {
-			logger.Fatal(`"config" accepts no argument %q`, args)
+			fmt.Printf("config accepts no argument %q\n", args)
+			os.Exit(1)
 		}
 
 	},
 }
 
 func init() {
-	InitConfigCmd.Flags().StringP("output", "o", "", "config file output")
+	InitConfigCmd.Flags().StringP("output", "o", "", "configuration file output")
+	InitConfigCmd.Flags().BoolP("force", "f", false, "Force overwrite configuration file")
 }

cmd/root.go

@@ -17,10 +17,11 @@ limitations under the License.
 package cmd
 
 import (
+	"fmt"
 	"github.com/jkaninda/goma-gateway/cmd/config"
-	"github.com/jkaninda/goma-gateway/pkg/logger"
 	"github.com/jkaninda/goma-gateway/util"
 	"github.com/spf13/cobra"
+	"os"
 )
 
 // rootCmd represents
@@ -29,7 +30,7 @@ var rootCmd = &cobra.Command{
 	Short:   "Goma Gateway is a lightweight API Gateway Management",
 	Long:    `.`,
 	Example: util.MainExample,
-	Version: util.FullVersion(),
+	Version: util.Version,
 }
 
 // Execute adds all child commands to the root command and sets flags appropriately.
@@ -37,7 +38,8 @@ var rootCmd = &cobra.Command{
 func Execute() {
 	err := rootCmd.Execute()
 	if err != nil {
-		logger.Fatal("Error executing root command %v", err)
+		fmt.Printf("Error executing root command %v\n", err)
+		os.Exit(1)
 	}
 }
 func init() {

cmd/server.go

@@ -21,9 +21,9 @@ import (
 	"fmt"
 	"github.com/common-nighthawk/go-figure"
 	"github.com/jkaninda/goma-gateway/internal"
-	"github.com/jkaninda/goma-gateway/pkg/logger"
 	"github.com/jkaninda/goma-gateway/util"
 	"github.com/spf13/cobra"
+	"os"
 )
 
 var ServerCmd = &cobra.Command{
@@ -39,11 +39,13 @@ var ServerCmd = &cobra.Command{
 		g := pkg.GatewayServer{}
 		gs, err := g.Config(configFile)
 		if err != nil {
-			logger.Fatal("Could not load configuration: %v", err)
+			fmt.Printf("Could not load configuration: %v\n", err)
+			os.Exit(1)
 		}
 		gs.SetEnv()
 		if err := gs.Start(ctx); err != nil {
-			logger.Fatal("Could not start server: %v", err)
+			fmt.Printf("Could not start server: %v\n", err)
+			os.Exit(1)
 
 		}
 
@@ -56,7 +58,7 @@ func init() {
 func intro() {
 	nameFigure := figure.NewFigure("Goma", "", true)
 	nameFigure.Print()
-	fmt.Printf("Version: %s\n", util.FullVersion())
+	fmt.Printf("Version: %s\n", util.Version)
 	fmt.Println("Copyright (c) 2024 Jonas Kaninda")
 	fmt.Println("Starting Goma Gateway server...")
 }

cmd/version.go

@@ -18,7 +18,6 @@
 package cmd
 
 import (
-	"fmt"
 	"github.com/jkaninda/goma-gateway/util"
 	"github.com/spf13/cobra"
 )
@@ -32,5 +31,5 @@ var VersionCmd = &cobra.Command{
 }
 
 func version() {
-	fmt.Println("Version:\t", util.FullVersion())
+	util.FullVersion()
 }

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) {
+func InitConfig(configFile string) error {
-	configFile, _ := cmd.Flags().GetString("output")
+	return initConfig(configFile)
-	if configFile == "" {
-		configFile = GetConfigPaths()
-	}
-	initConfig(configFile)
-	return
 
 }
 
 // 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 := pr.path
-		path, _ := route.GetPathTemplate()
+		if len(path) == 0 {
-		timer := prometheus.NewTimer(httpDuration.WithLabelValues(path))
+			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)

util/constants.go

@@ -10,26 +10,20 @@ You may get a copy of the License at
     http://www.apache.org/licenses/LICENSE-2.0
 */
 import (
-	"os"
+	"fmt"
 )
 
-var Version string
-
 const ConfigVersion = "1.0"
 
-func VERSION(def string) string {
+var Version = "development"
-	build := os.Getenv("VERSION")
+var buildTime string
-	if build == "" {
+var gitCommit string
-		return def
+
-	}
+func FullVersion() {
-	return build
+	fmt.Printf("Goma Gateway version: %s\n", Version)
-}
+	fmt.Printf("Configuration version: %s\n", ConfigVersion)
-func FullVersion() string {
+	fmt.Printf("Build time: %s\n", buildTime)
-	ver := Version
+	fmt.Printf("Git commit: %s\n", gitCommit)
-	if b := VERSION(""); b != "" {
-		return b
-	}
-	return ver
 }
 
 const MainExample = "Initialize config: config init --output config.yml\n" +