The One Fullstack Software Developer

Certainly! I am here to provide my expertise as a software developer and consultant. Based on your requirements, here is an architecture and code for developing a secure web app using Golang and Angular. Backend Architecture: We will use a microservice-based architecture to separate the functionalities of the web app into smaller, more manageable services. The backend will be developed using Golang, and we will use the following microservices: Authentication Service: Handles user registration, login, and JWT token generation. Product Service: Manages the products, including product creation, retrieval, and deletion. Marketplace Service: Provides functionalities related to the marketplace, such as searching for products, buying products, and managing transactions. Admin Service: Manages admin-related functionalities, such as user management and role-based access control (RBAC). Frontend Architecture: The frontend will be developed using Angular, and it will communicate with the backend microservices using RESTful APIs. Security Measures: JWT Authentication: Users will register and login to the system, and upon successful authentication, they will receive a JWT token. This token will be included in the headers of subsequent API requests for authorization. HTTPS: All communication between the client and server will be secured using HTTPS to protect against eavesdropping and data tampering. CSRF Protection: CSRF tokens will be generated on the server and included in HTML forms. When forms are submitted, the tokens will be included in the request headers, and the server will verify their validity to prevent CSRF attacks. Input Validation: All user inputs, including registration data, product information, and search queries, will be validated on the server-side to prevent malicious inputs and mitigate SQL injection and XSS attacks. Error Handling: Proper error handling will be implemented in the backend and frontend to provide meaningful error messages and prevent information leakage. Secure Password Storage: User passwords will be securely hashed using a strong hashing algorithm like bcrypt before storing in the database to prevent password-related security breaches. Here's an example code snippet for the backend authentication service using Golang and JWT: // auth_service.go package main import ( "fmt" "log" "net/http" "time" "github.com/dgrijalva/jwt-go" "github.com/gin-gonic/gin" "golang.org/x/crypto/bcrypt" ) var jwtKey = []byte("your_jwt_secret_key") type User struct { Username string `json:"username"` Password string `json:"password"` Role string `json:"role"` } type Claims struct { Username string `json:"username"` Role string `json:"role"` jwt.StandardClaims } func main() { router := gin.Default() // Register routes router.POST("/register", register) router.POST("/login", login) router.Run(":8080") } func register(c *gin.Context) { var user User if err := c.ShouldBindJSON(&user); err != nil { c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()}) return } // Validate and hash password hashedPassword, err := bcrypt.GenerateFromPassword([]byte(user.Password), bcrypt.DefaultCost) if err != nil { c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to hash password"}) return } // Save user data to database // ... c.Status(http.StatusOK) } func login(c *gin.Context) { var user User if err := c.ShouldBindJSON(&user); err != nil { c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()}) return } // Verify user credentials // ... // Generate JWT token expirationTime := time.Now().Add // auth_service.go package main import ( "fmt" "log" "net/http" "time" "github.com/dgrijalva/jwt-go" "github.com/gin-gonic/gin" "golang.org/x/crypto/bcrypt" ) var jwtKey = []byte("your_jwt_secret_key") type User struct { Username string `json:"username"` Password string `json:"password"` Role string `json:"role"` } type Claims struct { Username string `json:"username"` Role string `json:"role"` jwt.StandardClaims } func main() { router := gin.Default() // Register routes router.POST("/register", register) router.POST("/login", login) router.Run(":8080") } func register(c *gin.Context) { var user User if err := c.ShouldBindJSON(&user); err != nil { c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()}) return } // Validate and hash password hashedPassword, err := bcrypt.GenerateFromPassword([]byte(user.Password), bcrypt.DefaultCost) if err != nil { c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to hash password"}) return } // Save user data to database // ... c.Status(http.StatusOK) } func login(c *gin.Context) { var user User if err := c.ShouldBindJSON(&user); err != nil { c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()}) return } // Verify user credentials // ... // Generate JWT token expirationTime := time.Now().Add(24 * time.Hour) // Token expires after 24 hours claims := &Claims{ Username: user.Username, Role: user.Role, StandardClaims: jwt.StandardClaims{ ExpiresAt: expirationTime.Unix(), }, } token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims) tokenString, err := token.SignedString(jwtKey) if err != nil { c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to generate JWT token"}) return } c.JSON(http.StatusOK, gin.H{"token": tokenString}) } This code sets up a basic authentication service using Golang and Gin framework. It includes endpoints for user registration and login. The password is hashed using bcrypt before storing in the database. Upon successful login, a JWT token is generated with an expiration time of 24 hours, which includes the user's username and role as claims. The token is then returned to the client. Please note that this is a simplified example, and in a real-world application, you would need to implement additional security measures such as HTTPS, CSRF protection, input validation, error handling, and secure password storage in the appropriate services based on your specific requirements. On the frontend, you can use Angular to make API calls to the backend services and handle JWT token storage and usage in the client-side. You can also implement input validation and error handling in the Angular application to ensure a secure and robust user experience. I hope this helps you get started with developing a secure web app with Golang and Angular! Let me know if you have any further questions or need additional assistance.