From c8b16a204c9a6558bbbff8b293d308036c738f2c Mon Sep 17 00:00:00 2001
From: Jonas Kaninda <me@jonaskaninda.com>
Date: Sun, 24 Nov 2024 06:04:55 +0100
Subject: [PATCH] chore: add configuration validation

---
 internal/check_config.go | 40 ++++++++++++++++++++++++++++++++++++++++
 internal/middleware.go   |  2 +-
 internal/route_config.go |  1 +
 internal/routes.go       | 18 ++++--------------
 4 files changed, 46 insertions(+), 15 deletions(-)

diff --git a/internal/check_config.go b/internal/check_config.go
index 176ec99..50cf81d 100644
--- a/internal/check_config.go
+++ b/internal/check_config.go
@@ -19,12 +19,14 @@ package pkg
 
 import (
 	"fmt"
+	"github.com/jkaninda/goma-gateway/pkg/logger"
 	"github.com/jkaninda/goma-gateway/util"
 	"gopkg.in/yaml.v3"
 	"os"
 	"slices"
 )
 
+// CheckConfig checks configs
 func CheckConfig(fileName string) error {
 	if !util.FileExists(fileName) {
 		return fmt.Errorf("config file not found: %s", fileName)
@@ -81,6 +83,7 @@ func CheckConfig(fileName string) error {
 
 }
 
+// checkRoutes checks routes
 func checkRoutes(routes []Route, middlewares []Middleware) {
 	midNames := middlewareNames(middlewares)
 	for index, route := range routes {
@@ -106,6 +109,43 @@ func checkRoutes(routes []Route, middlewares []Middleware) {
 	}
 }
 
+// checkConfig checks configurations and returns error
+func checkConfig(routes []Route, middlewares []Middleware) error {
+	logger.Info("Checking configurations...")
+	midNames := middlewareNames(middlewares)
+	for index, route := range routes {
+		if len(route.Name) == 0 {
+			logger.Warn("Warning: route name is empty, index: [%d]", index)
+		}
+		if route.Destination == "" && len(route.Backends) == 0 {
+			return fmt.Errorf("Error: no destination or backends specified for route: %s | index: [%d] \n", route.Name, index)
+		}
+		// checking middleware applied to routes
+		for _, middleware := range route.Middlewares {
+			if !slices.Contains(midNames, middleware) {
+				logger.Warn("Couldn't find a middleware with the name: %s | route: %s", middleware, route.Name)
+			}
+		}
+	}
+
+	// find duplicated middleware name
+	duplicates := findDuplicateMiddlewareNames(dynamicMiddlewares)
+	if len(duplicates) != 0 {
+		for _, duplicate := range duplicates {
+			return fmt.Errorf("duplicated middleware name: %s, the name of the middleware should be unique", duplicate)
+		}
+	}
+	// find duplicated route name
+	duplicates = findDuplicateRouteNames(dynamicRoutes)
+	if len(duplicates) != 0 {
+		for _, duplicate := range duplicates {
+			logger.Warn("Duplicated route name was found: %s ", duplicate)
+		}
+	}
+	return nil
+}
+
+// middlewareNames reruns middleware names
 func middlewareNames(middlewares []Middleware) []string {
 	names := []string{}
 	for _, mid := range middlewares {
diff --git a/internal/middleware.go b/internal/middleware.go
index 9339cff..6f519bc 100644
--- a/internal/middleware.go
+++ b/internal/middleware.go
@@ -17,7 +17,7 @@ func getMiddleware(rules []string, middlewares []Middleware) (Middleware, error)
 		continue
 	}
 
-	return Middleware{}, errors.New("middlewares not found with name:  [" + strings.Join(rules, ";") + "]")
+	return Middleware{}, errors.New("middleware not found with name:  [" + strings.Join(rules, ";") + "]")
 }
 
 func doesExist(tyName string) bool {
diff --git a/internal/route_config.go b/internal/route_config.go
index 1ca3cc6..ba8307b 100644
--- a/internal/route_config.go
+++ b/internal/route_config.go
@@ -49,6 +49,7 @@ func loadExtraRoutes(routePath string) ([]Route, error) {
 	return extraRoutes, nil
 }
 
+// findDuplicateRouteNames finds duplicated route names
 func findDuplicateRouteNames(routes []Route) []string {
 	// Create a map to track occurrences of names
 	nameMap := make(map[string]int)
diff --git a/internal/routes.go b/internal/routes.go
index fa84671..592acde 100644
--- a/internal/routes.go
+++ b/internal/routes.go
@@ -56,20 +56,10 @@ func (gatewayServer GatewayServer) Initialize() *mux.Router {
 		logger.Info("Loaded %d additional routes", len(extraRoutes))
 
 	}
-
-	// find duplicated middleware name
-	duplicates := findDuplicateMiddlewareNames(dynamicMiddlewares)
-	if len(duplicates) != 0 {
-		for _, duplicate := range duplicates {
-			logger.Fatal("Duplicated middleware name: %s, the name of the middleware should be unique.", duplicate)
-		}
-	}
-	// find duplicated route name
-	duplicates = findDuplicateRouteNames(dynamicRoutes)
-	if len(duplicates) != 0 {
-		for _, duplicate := range duplicates {
-			logger.Error("Duplicated route name was found: %s ", duplicate)
-		}
+	// Check configs
+	err = checkConfig(dynamicRoutes, dynamicMiddlewares)
+	if err != nil {
+		logger.Fatal("Error: %v", err)
 	}
 	m := dynamicMiddlewares
 	redisBased := false