Implement Backend Functionality for Email Sending

src/main/java/com/libraryman_api/newsletter/EmailService1.java

@@ -0,0 +1,32 @@
+package com.libraryman_api.newsletter;
+
+
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.MimeMessage;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.stereotype.Service;
+
+@Service
+public class EmailService1 {
+
+    private final JavaMailSender mailSender;
+
+    public EmailService1(JavaMailSender mailSender) {
+        this.mailSender = mailSender;
+    }
+
+    public void send(String to, String body, String subject, Object notification) {
+        try {
+            MimeMessage mimeMessage = mailSender.createMimeMessage();
+            MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, "utf-8");
+            helper.setText(body, true);
+            helper.setTo(to);
+            helper.setSubject(subject);
+            helper.setFrom("[email protected]");
+            mailSender.send(mimeMessage);
+        } catch (MessagingException e) {
+            throw new IllegalStateException("Failed to send email", e);
+        }
+    }
+}

src/main/java/com/libraryman_api/newsletter/MailConfig.java

@@ -0,0 +1,27 @@
+package com.libraryman_api.newsletter;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.JavaMailSenderImpl;
+
+import java.util.Properties;
+
+@Configuration
+public class MailConfig {
+
+    @Bean
+    public JavaMailSender javaMailSender() {
+        JavaMailSenderImpl mailSender = new JavaMailSenderImpl();
+        mailSender.setHost("smtp.gmail.com");
+        mailSender.setPort(587);
+        mailSender.setUsername("[email protected]");
+        mailSender.setPassword("your-password");
+
+        Properties props = mailSender.getJavaMailProperties();
+        props.put("mail.transport.protocol", "smtp");
+        props.put("mail.smtp.auth", "true");
+        props.put("mail.smtp.starttls.enable", "true");
+        return mailSender;
+    }
+}

src/main/java/com/libraryman_api/newsletter/NewsletterController.java

@@ -1,44 +1,26 @@
 package com.libraryman_api.newsletter;
 
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
-import java.util.Map;
-
 @RestController
-@RequestMapping("/api/newsletter")
+@RequestMapping("/newsletter")
 public class NewsletterController {
 
+    private final NewsletterService newsletterService;
+
     @Autowired
-    private NewsletterService newsletterService;
+    public NewsletterController(NewsletterService newsletterService) {
+        this.newsletterService = newsletterService;
+    }
 
-    // Subscribe endpoint
     @PostMapping("/subscribe")
-    public ResponseEntity<String> subscribe(@RequestBody Map<String, String> requestBody) {
-        String email = requestBody.get("email");
-
-        // Call the service to handle subscription
-        String response = newsletterService.subscribe(email);
-
-        // Return response from the service
-        if (response.equals("Invalid email format.") || response.equals("Email is already subscribed.")) {
-            return ResponseEntity.badRequest().body(response);
-        }
-
-        return ResponseEntity.ok(response);
+    public String subscribe(@RequestParam String email) {
+        return newsletterService.subscribe(email);
     }
 
-    // Unsubscribe endpoint using token
-    @GetMapping("/unsubscribe/{token}")
-    public ResponseEntity<String> unsubscribe(@PathVariable String token) {
-        String response = newsletterService.unsubscribe(token);
-
-        // Check if the response indicates an error
-        if (response.equals("Invalid or expired token.") || response.equals("You are already unsubscribed.")) {
-            return ResponseEntity.badRequest().body(response);
-        }
-
-        return ResponseEntity.ok(response);
+    @GetMapping("/unsubscribe")
+    public String unsubscribe(@RequestParam String token) {
+        return newsletterService.unsubscribe(token);
     }
 }

src/main/java/com/libraryman_api/newsletter/NewsletterService.java

@@ -1,74 +1,73 @@
 package com.libraryman_api.newsletter;
 
+import com.libraryman_api.email.EmailService;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
-
 import java.util.Optional;
-import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 @Service
 public class NewsletterService {
 
+    private final NewsletterSubscriberRepository subscriberRepository;
+    private final EmailService emailService;
+
     @Autowired
-    private NewsletterSubscriberRepository subscriberRepository;
+    public NewsletterService(NewsletterSubscriberRepository subscriberRepository, EmailService emailService) {
+        this.subscriberRepository = subscriberRepository;
+        this.emailService = emailService;
+    }
 
-    // Subscribe user after validating email
     public String subscribe(String email) {
-        if (!isValidEmail(email)) {
-            return "Invalid email format.";
-        }
+        if (!isValidEmail(email)) return "Invalid email format.";
 
-        // Check if the email already exists
         Optional<NewsletterSubscriber> optionalSubscriber = subscriberRepository.findByEmail(email);
-
         if (optionalSubscriber.isPresent()) {
             NewsletterSubscriber subscriber = optionalSubscriber.get();
-
-            // If the subscriber is inactive, reactivate them
             if (!subscriber.isActive()) {
-                subscriber.setActive(true); // Reactivate the subscriber
-                subscriber.regenerateToken(); // Generate a new token
-                subscriberRepository.save(subscriber); // Save the updated subscriber
+                subscriber.setActive(true);
+                subscriber.regenerateToken();
+                subscriberRepository.save(subscriber);
+                sendSubscriptionEmail(email, subscriber.getUnsubscribeToken());
                 return "You have successfully re-subscribed!";
-            } else {
-                return "Email is already subscribed.";
             }
+            return "Email is already subscribed.";
         }
 
-        // Save new subscriber if not present
-        NewsletterSubscriber subscriber = new NewsletterSubscriber(email);
-        subscriberRepository.save(subscriber);
+        NewsletterSubscriber newSubscriber = new NewsletterSubscriber(email);
+        subscriberRepository.save(newSubscriber);
+        sendSubscriptionEmail(email, newSubscriber.getUnsubscribeToken());
         return "You have successfully subscribed!";
     }
 
-    // Unsubscribe user using the token
     public String unsubscribe(String token) {
         Optional<NewsletterSubscriber> optionalSubscriber = subscriberRepository.findByUnsubscribeToken(token);
-
-        if (optionalSubscriber.isEmpty()) {
-            return "Invalid or expired token.";
-        }
+        if (optionalSubscriber.isEmpty()) return "Invalid or expired token.";
 
         NewsletterSubscriber subscriber = optionalSubscriber.get();
+        if (!subscriber.isActive()) return "You are already unsubscribed.";
 
-        if (!subscriber.isActive()) {
-            return "You are already unsubscribed.";
-        }
-
-        subscriber.setActive(false); // Set active to false
-        subscriberRepository.save(subscriber); // Save the updated subscriber
+        subscriber.setActive(false);
+        subscriberRepository.save(subscriber);
+        sendUnsubscribeEmail(subscriber.getEmail());
         return "You have successfully unsubscribed!";
     }
 
-    // Email validation logic
     private boolean isValidEmail(String email) {
-        if (email == null || email.trim().isEmpty()) {
-            return false;
-        }
         String emailRegex = "^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,}$";
-        Pattern pattern = Pattern.compile(emailRegex);
-        Matcher matcher = pattern.matcher(email);
-        return matcher.matches();
+        return Pattern.compile(emailRegex).matcher(email).matches();
+    }
+
+    private void sendSubscriptionEmail(String email, String token) {
+        String subject = "Welcome to Our Newsletter!";
+        String body = "Thank you for subscribing! To unsubscribe, click the link:\n" +
+                "http://localhost:8080/newsletter/unsubscribe?token=" + token;
+        emailService.send(email, body, subject, null);
+    }
+
+    private void sendUnsubscribeEmail(String email) {
+        String subject = "You have been unsubscribed";
+        String body = "You have successfully unsubscribed. If this was a mistake, you can re-subscribe.";
+        emailService.send(email, body, subject, null);
     }
 }

src/main/java/com/libraryman_api/newsletter/NewsletterSubscriber.java

@@ -1,7 +1,6 @@
 package com.libraryman_api.newsletter;
 
 import jakarta.persistence.*;
-
 import java.util.UUID;
 
 @Entity
@@ -16,53 +15,28 @@ public class NewsletterSubscriber {
     private String email;
 
     @Column(nullable = false)
-    private boolean active = true; // Manage subscription status
+    private boolean active = true;
 
     @Column(name = "unsubscribe_token", nullable = false, unique = true)
-    private String unsubscribeToken; // Token for unsubscribing
+    private String unsubscribeToken;
 
-    // Default constructor that initializes the token
+    // Default constructor initializing unsubscribe token
     public NewsletterSubscriber() {
-        this.unsubscribeToken = UUID.randomUUID().toString(); // Generate token by default
+        this.unsubscribeToken = UUID.randomUUID().toString();
     }
 
-    // Constructor to initialize with email
+    // Constructor initializing with email
     public NewsletterSubscriber(String email) {
         this();
         this.email = email;
     }
 
-    // Getters and setters
-    public Long getId() {
-        return id;
-    }
-
-    public void setId(Long id) {
-        this.id = id;
-    }
-
-    public String getEmail() {
-        return email;
-    }
-
-    public void setEmail(String email) {
-        this.email = email;
-    }
-
-    public boolean isActive() {
-        return active;
-    }
-
-    public void setActive(boolean active) {
-        this.active = active;
-    }
-
-    public String getUnsubscribeToken() {
-        return unsubscribeToken;
-    }
-
-    // Method to regenerate a new token
-    public void regenerateToken() {
-        this.unsubscribeToken = UUID.randomUUID().toString();
-    }
+    // Getters and Setters
+    public Long getId() { return id; }
+    public String getEmail() { return email; }
+    public void setEmail(String email) { this.email = email; }
+    public boolean isActive() { return active; }
+    public void setActive(boolean active) { this.active = active; }
+    public String getUnsubscribeToken() { return unsubscribeToken; }
+    public void regenerateToken() { this.unsubscribeToken = UUID.randomUUID().toString(); }
 }

src/main/java/com/libraryman_api/newsletter/NewsletterSubscriberRepository.java

@@ -1,14 +1,9 @@
 package com.libraryman_api.newsletter;
 
 import org.springframework.data.jpa.repository.JpaRepository;
-
 import java.util.Optional;
 
 public interface NewsletterSubscriberRepository extends JpaRepository<NewsletterSubscriber, Long> {
-
-    // Find a subscriber by email
     Optional<NewsletterSubscriber> findByEmail(String email);
-
-    // Find a subscriber by unsubscribe token
     Optional<NewsletterSubscriber> findByUnsubscribeToken(String unsubscribeToken);
 }

src/main/resources/application-development.properties

@@ -42,10 +42,8 @@ spring.mail.properties.mail.smtp.auth=Add_Your_Mail_Service_SMTP
 spring.mail.properties.mail.starttls.enable=Add_Your_Mail_Service_Start_TLS
 spring.mail.properties.domain_name=Add_Your_Mail_Service_Domain_Name
 
-
-
 # --- Oauth 2.0 Configurations ---
 spring.security.oauth2.client.registration.google.client-name=google
 spring.security.oauth2.client.registration.google.client-id=ADD_YOUR_CLIENT_ID
 spring.security.oauth2.client.registration.google.client-secret=ADD_YOUR_SECRET_KEY
-spring.security.oauth2.client.registration.google.scope=email,profile
+spring.security.oauth2.client.registration.google.scope=email,profile