feat(constants): add new constants for error, success, and info messages to improve code readability and maintainability

fix(main.go): replace hardcoded error messages with constants for better consistency and easier updates
fix(handlers.go): update API version response to a fixed version string for clarity and consistency

Author: anqorithm

cmd/api/main.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/anqorithm/naqa-api/internal/config"
+	"github.com/anqorithm/naqa-api/internal/constants"
 	"github.com/anqorithm/naqa-api/internal/middleware"
 	"github.com/anqorithm/naqa-api/internal/routes"
 	"github.com/anqorithm/naqa-api/internal/seeders"
@@ -23,20 +24,20 @@ func main() {
 	mongoConfig := config.NewMongoConfig()
 	db, err := config.ConnectDB(mongoConfig)
 	if err != nil {
-		log.Fatal("Database Connection Error: ", err)
+		log.Fatal(constants.ErrDatabaseConnection, err)
 	}
 
 	// ###############################################################################
 	// Data Seeding
 	// ###############################################################################
 	shouldSeed := strings.ToLower(os.Getenv("SEED_DATA")) == "true"
 	if shouldSeed {
-		log.Println("Starting data seeding process...")
+		log.Println(constants.InfoStartingSeeding)
 		if err := seeders.LoadDataSources(db); err != nil {
-			log.Printf("Warning: Error seeding data: %v", err)
+			log.Printf("Warning: %s: %v", constants.ErrDataSeeding, err)
 		}
 	} else {
-		log.Println("Skipping data seeding (SEED_DATA is not set to 'true')")
+		log.Println(constants.InfoSkippingSeeding)
 	}
 
 	// ###############################################################################
@@ -68,6 +69,6 @@ func main() {
 		port = "3000"
 	}
 
-	log.Printf("Server starting on port %s", port)
+	log.Printf(constants.InfoServerStarting, port)
 	log.Fatal(app.Listen(":" + port))
 }

internal/constants/constants.go

@@ -9,29 +9,60 @@ const DateFormat = "2006-01-02"
 
 // Error codes
 const (
-	ErrCodeInvalidRequest      = "INVALID_REQUEST"
-	ErrCodeValidationFailed    = "VALIDATION_FAILED"
-	ErrCodeDatabaseError       = "DATABASE_ERROR"
-	ErrCodeNotFound            = "NOT_FOUND"
-	ErrCodeInvalidData         = "INVALID_DATA"
+	ErrCodeInvalidRequest   = "INVALID_REQUEST"
+	ErrCodeValidationFailed = "VALIDATION_FAILED"
+	ErrCodeDatabaseError    = "DATABASE_ERROR"
+	ErrCodeNotFound         = "NOT_FOUND"
+	ErrCodeInvalidData      = "INVALID_DATA"
 )
 
 // Error messages
 const (
-	MsgInvalidRequestBody        = "Invalid request body"
-	MsgValidationFailed          = "Validation failed"
-	MsgInvalidStartDateFormat    = "Invalid start date format. Use YYYY-MM-DD."
-	MsgInvalidEndDateFormat      = "Invalid end date format. Use YYYY-MM-DD."
-	MsgEndDateAfterStartDate     = "End date must be greater than start date."
-	MsgStockNotFound             = "Stock not found"
-	MsgInvalidPurificationRate   = "Invalid purification rate in database"
+	MsgInvalidRequestBody      = "Invalid request body"
+	MsgValidationFailed        = "Validation failed"
+	MsgInvalidStartDateFormat  = "Invalid start date format. Use YYYY-MM-DD."
+	MsgInvalidEndDateFormat    = "Invalid end date format. Use YYYY-MM-DD."
+	MsgEndDateAfterStartDate   = "End date must be greater than start date."
+	MsgStockNotFound           = "Stock not found"
+	MsgInvalidPurificationRate = "Invalid purification rate in database"
 )
 
 // Available years for stock data
 var AvailableYears = []string{"2015", "2016", "2017", "2018", "2019", "2020", "2021", "2022", "2023"}
 
 // Monitor titles
 const (
-    MonitorTitleAr = "لوحة مراقبة نقاء"
-    MonitorTitleEn = "NAQA Monitoring Dashboard"
+	MonitorTitleAr = "لوحة مراقبة نقاء"
+	MonitorTitleEn = "NAQA Monitoring Dashboard"
+)
+
+// Error Messages
+const (
+	ErrDatabaseConnection = "Database Connection Error"
+	ErrDataSeeding        = "Error seeding data"
+	ErrInternalServer     = "Internal Server Error"
+	ErrInvalidInput       = "Invalid input data"
+	ErrNotFound           = "Resource not found"
+	ErrUnauthorized       = "Unauthorized access"
+)
+
+// Success Messages
+const (
+	SuccessDataSeeded    = "Data seeding completed successfully"
+	SuccessServerStarted = "Server started successfully"
+	SuccessHealthCheck   = "Health check passed"
+)
+
+// Info Messages
+const (
+	InfoSkippingSeeding = "Skipping data seeding (SEED_DATA is not set to 'true')"
+	InfoStartingSeeding = "Starting data seeding process..."
+	InfoServerStarting  = "Server starting on port %s"
+)
+
+// Validation Messages
+const (
+	ValidateRequiredField = "This field is required"
+	ValidateInvalidEmail  = "Invalid email format"
+	ValidateInvalidInput  = "Invalid input format"
 )

internal/handlers/handlers.go

@@ -1,9 +1,5 @@
 package handlers
 
-// ###############################################################################
-// Handler Functions
-// ###############################################################################
-
 import (
 	"fmt"
 	"os"
@@ -25,6 +21,10 @@ func NewHandler(db *mongo.Database) *Handler {
 	}
 }
 
+// ###############################################################################
+// Handler Functions
+// ###############################################################################
+
 // RootHandler handles the "/" endpoint
 func (h *Handler) RootHandler(c *fiber.Ctx) error {
 	return c.JSON(fiber.Map{
@@ -42,7 +42,7 @@ func (h *Handler) ApiV1Handler(c *fiber.Ctx) error {
 	return c.JSON(fiber.Map{
 		"status":      "active",
 		"message":     "Welcome to NAQA API v1",
-		"version":     os.Getenv("API_VERSION"),
+		"version":     "1.0.0",
 		"env":         os.Getenv("ENVIRONMENT"),
 		"server_time": time.Now().Format(time.RFC3339),
 		"request_id":  c.Get("X-Request-ID", uuid.New().String()),
@@ -57,8 +57,10 @@ func (h *Handler) ApiV1Handler(c *fiber.Ctx) error {
 // HealthCheckHandler handles the health check endpoint
 func (h *Handler) HealthCheckHandler(c *fiber.Ctx) error {
 	return c.JSON(fiber.Map{
-		"status":    "OK",
-		"timestamp": time.Now().Format(time.RFC3339),
+		"status":     "OK",
+		"timestamp":  time.Now().Format(time.RFC3339),
+		"message":    constants.SuccessHealthCheck,
+		"request_id": c.Get("X-Request-ID", uuid.New().String()),
 	})
 }