feat: migrate Flask API to Go with JWT auth

pkg/database/db.go

@@ -0,0 +1,43 @@
+package database
+
+import (
+	"fmt"
+	"log"
+	"os"
+
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+)
+
+var DB *gorm.DB
+
+func Init() {
+	dsn := fmt.Sprintf(
+		"host=%s user=%s password=%s dbname=%s port=%s sslmode=disable",
+		os.Getenv("PG_HOST"),
+		os.Getenv("PG_USER"),
+		os.Getenv("PG_PASSWORD"),
+		os.Getenv("PG_DATABASE"),
+		os.Getenv("PG_PORT"),
+	)
+
+	var err error
+	DB, err = gorm.Open(postgres.Open(dsn), &gorm.Config{})
+	if err != nil {
+		log.Fatalf("Failed to connect to database: %v", err)
+	}
+
+	log.Println("Database connected successfully")
+}
+
+func Migrate(models ...interface{}) error {
+	return DB.AutoMigrate(models...)
+}
+
+func Close() error {
+	sqlDB, err := DB.DB()
+	if err != nil {
+		return err
+	}
+	return sqlDB.Close()
+}

pkg/errors/errors.go

@@ -0,0 +1,26 @@
+package errors
+
+type AppError struct {
+	Code    int
+	Message string
+	Details string
+}
+
+func (e *AppError) Error() string {
+	return e.Message
+}
+
+func NewAppError(code int, message, details string) *AppError {
+	return &AppError{
+		Code:    code,
+		Message: message,
+		Details: details,
+	}
+}
+
+var (
+	ErrUnauthorized = NewAppError(401, "Unauthorized", "")
+	ErrNotFound     = NewAppError(404, "Not Found", "")
+	ErrBadRequest   = NewAppError(400, "Bad Request", "")
+	ErrInternal     = NewAppError(500, "Internal Server Error", "")
+)

pkg/utils/utils.go

@@ -0,0 +1,16 @@
+package utils
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+func JSONResponse(w http.ResponseWriter, code int, payload interface{}) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(code)
+	json.NewEncoder(w).Encode(payload)
+}
+
+func JSONError(w http.ResponseWriter, code int, message string) {
+	JSONResponse(w, code, map[string]string{"error": message})
+}