Add solution for gin challenge-1-basic-routing

Author: go-interview-practice-bot[bot]

packages/gin/challenge-1-basic-routing/submissions/RuslanG003/solution.go

@@ -0,0 +1,289 @@
+package main
+
+import (
+	"errors"
+	"net/http"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+)
+
+// User represents a user in our system
+type User struct {
+	ID    int    `json:"id"`
+	Name  string `json:"name"`
+	Email string `json:"email"`
+	Age   int    `json:"age"`
+}
+
+// Response represents a standard API response
+type Response struct {
+	Success bool        `json:"success"`
+	Data    interface{} `json:"data,omitempty"`
+	Message string      `json:"message,omitempty"`
+	Error   string      `json:"error,omitempty"`
+	Code    int         `json:"code,omitempty"`
+}
+
+// In-memory storage
+var users = []User{
+	{ID: 1, Name: "John Doe", Email: "john@example.com", Age: 30},
+	{ID: 2, Name: "Jane Smith", Email: "jane@example.com", Age: 25},
+	{ID: 3, Name: "Bob Wilson", Email: "bob@example.com", Age: 35},
+}
+var nextID = 4
+
+//main.go starts herez
+func main() {
+	// TODO: Create Gin router
+	router := gin.Default()
+
+	// TODO: Setup routes
+	router.GET("/users", getAllUsers)        // GET /users - Get all users
+	router.GET("/users/:id", getUserByID)    // GET /users/:id - Get user by ID
+	router.POST("/users", createUser)        // POST /users - Create new user
+	router.PUT("/users/:id", updateUser)     // PUT /users/:id - Update user
+	router.DELETE("/users/:id", deleteUser)  // DELETE /users/:id - Delete user
+	router.GET("/users/search", searchUsers) // GET /users/search - Search users by name
+
+	router.Run(":8080") // TODO: Start server on http://localhost:8080
+}
+
+// TODO: Implement handler functions
+
+// getAllUsers handles GET /users
+func getAllUsers(c *gin.Context) {
+	// TODO: Return all users
+	c.JSON(http.StatusOK, Response{
+		Success: true,
+		Data:    users,
+	})
+}
+
+// getUserByID handles GET /users/:id
+func getUserByID(c *gin.Context) {
+	// TODO: Get user by ID
+	userID, err := strconv.Atoi(c.Param("id"))
+
+	// Handle invalid ID format
+	if err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "Invalid ID format",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+	foundUser, index := findUserByID(userID)
+	// Return 404 if user not found
+	if index == -1 {
+		c.JSON(http.StatusNotFound, Response{
+			Success: false,
+			Error:   "404: User not found",
+			Code:    http.StatusNotFound,
+		})
+		return
+	}
+	c.JSON(http.StatusOK, Response{
+		Success: true,
+		Data:    foundUser,
+	})
+}
+
+// createUser handles POST /users
+func createUser(c *gin.Context) {
+	// TODO: Parse JSON request body
+	var newUser User // Validate required fields
+	if err := c.ShouldBindJSON(&newUser); err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "Invalid JSON format",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+
+	if err := validateUser(newUser); err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   err.Error(),
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+	newUser.ID = nextID
+	nextID++
+	users = append(users, newUser) // Add user to storage
+	// Return created user
+	c.JSON(http.StatusCreated, Response{
+		Success: true,
+		Data:    newUser,
+		Message: "User creation was done",
+	})
+}
+
+// updateUser handles PUT /users/:id
+func updateUser(c *gin.Context) {
+	// TODO: Get user ID from path
+	userID, err := strconv.Atoi(c.Param("id"))
+
+	if err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "Invalid user ID format",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+
+	_, index := findUserByID(userID) //- так вроде правильно
+	if index < 0 {
+		c.JSON(http.StatusNotFound, Response{
+			Success: false,
+			Error:   "User not found",
+			Code:    http.StatusNotFound,
+		})
+		return
+	}
+	var updatedUser User
+	if err := c.ShouldBindJSON(&updatedUser); err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "invalid JSON format",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+	updatedUser.ID = userID
+
+	if err := validateUser(updatedUser); err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   err.Error(),
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+
+	users[index] = updatedUser
+
+	// Parse JSON request body
+	// Find and update user
+	// Return updated user
+	c.JSON(http.StatusOK, Response{
+		Success: true,
+		Data:    updatedUser,
+		Message: "User updated Succsesfully",
+	})
+}
+
+// deleteUser handles DELETE /users/:id
+func deleteUser(c *gin.Context) {
+	// TODO: Get user ID from path
+	if c == nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "User not found",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+	userID, err := strconv.Atoi(c.Param("id"))
+
+	if err != nil {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "Invalid user ID format",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+
+	if userID < 0 {
+		c.JSON(http.StatusNotFound, Response{
+			Success: false,
+			Error:   "User not found",
+			Code:    http.StatusNotFound,
+		})
+		return
+	}
+
+	_, index := findUserByID(userID)
+	if index < 0 {
+		c.JSON(http.StatusNotFound, Response{
+			Success: false,
+			Error:   "User not found",
+			Code:    http.StatusNotFound,
+		})
+		return
+	}
+	// Find and remove user
+	// Return success message
+	users = append(users[:index], users[index+1:]...)
+	c.JSON(http.StatusOK, Response{
+		Success: true,
+		Message: "User deleted Succsesfully",
+	})
+}
+
+// searchUsers handles GET /users/search?name=value
+func searchUsers(c *gin.Context) {
+	// TODO: Get name query parameter
+	nameQuery := c.Query("name")
+	if nameQuery == "" {
+		c.JSON(http.StatusBadRequest, Response{
+			Success: false,
+			Error:   "Missing 'name' query parameter",
+			Code:    http.StatusBadRequest,
+		})
+		return
+	}
+	var matchedUsers []User
+	for _, u := range users {
+		if strings.Contains(strings.ToLower(u.Name), strings.ToLower(nameQuery)) {
+			matchedUsers = append(matchedUsers, u)
+		}
+	}
+	// Filter users by name (case-insensitive)
+	if matchedUsers == nil {
+		matchedUsers = make([]User, 0) // или []User{}
+	}
+	// Return matching users
+	c.JSON(http.StatusOK, Response{
+		Success: true,
+		Data:    matchedUsers,
+		Message: "Search completed",
+		Code:    http.StatusOK,
+	})
+}
+
+// Helper function to find user by ID
+func findUserByID(id int) (*User, int) {
+	// TODO: Implement user lookup
+	for i, u := range users {
+		if u.ID == id {
+			return &users[i], i
+		}
+	}
+	// Return user pointer and index, or nil and -1 if not found
+	return nil, -1
+}
+
+// Helper function to validate user data
+func validateUser(user User) error {
+	// TODO: Implement validation
+	// Check required fields: Name, Email
+	if user.Name == "" {
+		return errors.New("Name is required")
+	}
+	if user.Email == "" {
+		return errors.New("Email is required")
+	}
+	if matched, _ := regexp.MatchString(`^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,}$`, user.Email); !matched {
+		return errors.New("Email is invalid")
+	}
+	//
+	return nil
+}