feat: Add SMTP support for self-hosted Postal mail server

backend/services/email_service.py

@@ -1,9 +1,12 @@
 """
-Email Service - Mailgun (primary) with AWS SES fallback
+Email Service - Postal SMTP (primary), Mailgun, or AWS SES fallback
 """
 import os
 import httpx
 import secrets
+import smtplib
+from email.mime.text import MIMEText
+from email.mime.multipart import MIMEMultipart
 from datetime import datetime, timedelta
 from typing import Optional
 
@@ -18,7 +21,14 @@ except ImportError:
 
 class EmailService:
     def __init__(self):
-        # Mailgun settings (primary)
+        # Postal SMTP settings (primary - self-hosted)
+        self.smtp_host = os.getenv("SMTP_HOST")
+        self.smtp_port = int(os.getenv("SMTP_PORT", "25"))
+        self.smtp_username = os.getenv("SMTP_USERNAME")
+        self.smtp_password = os.getenv("SMTP_PASSWORD")
+        self.smtp_use_tls = os.getenv("SMTP_USE_TLS", "true").lower() == "true"
+        
+        # Mailgun settings (alternative)
         self.mailgun_api_key = os.getenv("MAILGUN_API_KEY")
         self.mailgun_domain = os.getenv("MAILGUN_DOMAIN")
         self.mailgun_api_base = os.getenv("MAILGUN_API_BASE", "https://api.mailgun.net/v3")
@@ -32,8 +42,11 @@ class EmailService:
         self.email_from = os.getenv("EMAIL_FROM", "noreply@elmeg.xyz")
         self.frontend_url = os.getenv("FRONTEND_URL", "https://elmeg.xyz")
         
-        # Determine which provider to use
+        # Determine which provider to use (priority: SMTP -> Mailgun -> SES -> Dummy)
-        if self.mailgun_api_key and self.mailgun_domain:
+        if self.smtp_host and self.smtp_username and self.smtp_password:
+            self.provider = "smtp"
+            print(f"Email service: Using SMTP ({self.smtp_host}:{self.smtp_port})")
+        elif self.mailgun_api_key and self.mailgun_domain:
             self.provider = "mailgun"
             print(f"Email service: Using Mailgun ({self.mailgun_domain})")
         elif BOTO3_AVAILABLE and self.aws_access_key_id and self.aws_secret_access_key:
@@ -51,13 +64,45 @@ class EmailService:
 
     def send_email(self, to_email: str, subject: str, html_content: str, text_content: str):
         """Send an email using configured provider"""
-        if self.provider == "mailgun":
+        if self.provider == "smtp":
+            return self._send_smtp(to_email, subject, html_content, text_content)
+        elif self.provider == "mailgun":
             return self._send_mailgun(to_email, subject, html_content, text_content)
         elif self.provider == "ses":
             return self._send_ses(to_email, subject, html_content, text_content)
         else:
             return self._send_dummy(to_email, subject, text_content)
 
+    def _send_smtp(self, to_email: str, subject: str, html_content: str, text_content: str):
+        """Send email via SMTP (Postal or any SMTP server)"""
+        try:
+            # Create message
+            msg = MIMEMultipart("alternative")
+            msg["Subject"] = subject
+            msg["From"] = f"Elmeg <{self.email_from}>"
+            msg["To"] = to_email
+            
+            # Attach text and HTML parts
+            msg.attach(MIMEText(text_content, "plain"))
+            msg.attach(MIMEText(html_content, "html"))
+            
+            # Connect and send
+            if self.smtp_use_tls:
+                server = smtplib.SMTP(self.smtp_host, self.smtp_port)
+                server.starttls()
+            else:
+                server = smtplib.SMTP(self.smtp_host, self.smtp_port)
+            
+            server.login(self.smtp_username, self.smtp_password)
+            server.sendmail(self.email_from, to_email, msg.as_string())
+            server.quit()
+            
+            print(f"Email sent via SMTP to {to_email}")
+            return True
+        except Exception as e:
+            print(f"Error sending email via SMTP: {e}")
+            return False
+
     def _send_mailgun(self, to_email: str, subject: str, html_content: str, text_content: str):
         """Send email via Mailgun API"""
         try: