dev Split Email

[DevCEDTeam]

flowchart TD
    A[Inbound Email Message] --> B(MX Records via Cloudflare)
    B --> B1(route1.mx.cloudflare.net Priority: 2)
    B --> B2(route2.mx.cloudflare.net Priority: 81)
    B --> B3(route3.mx.cloudflare.net Priority: 91)
    B --> C(Cloudflare Worker: workers-n8n-4)
    C --> D(Google Cloud Function Processes the email)
    D --> D1(Bounce management IMAP)
    D --> D2(Open tracking pixel tracking)
    D --> D3(Unsubscribe handling Webhook)
    D --> D4(OAuth 2.0 for Gmail)
    D --> E(Firestore/MongoDB Stores email metadata)
    E --> E1(Bounce, open, unsubscribe data)
    E --> F(Outbound Email Routing Mailhop server a970359.mx.mailhop.org)

[DevCEDTeam]

Updated Step-by-Step Instructions: Bounce Management, Email Open Tracking, Unsubscribe Handling Using Terraform, Google Cloud, and Cloudflare

Based on the provided flowchart and system architecture, the following is a revised and detailed step-by-step guide to set up an email management system using open-source tools (IMAP, SMTP, and webhooks) along with Terraform and Cloudflare for infrastructure setup.

---

Objective:

As an email administrator, set up a system to manage:

1. Bounced Emails (using IMAP monitoring).
2. Email Open Tracking (using a tracking pixel).
3. Unsubscribe Handling (with a custom unsubscribe link).

We’ll use Python scripts to handle these tasks, IMAP for bounce tracking, SMTP for sending emails, and tracking pixels for open monitoring.

---

Infrastructure Setup (Terraform and Cloudflare)

Step 1: Setting up Google Cloud Infrastructure Using Terraform

We will use Terraform to create the necessary Google Cloud infrastructure, such as the VPC, Cloud Functions, and Firestore/MongoDB for data storage.

1. Install Terraform:
   Make sure you have Terraform installed.

   • Install Terraform

2. Create a Terraform Configuration File (main.tf):

provider "google" {
  credentials = file("path/to/your-service-account.json")
  project     = "your-gcp-project-id"
  region      = "us-central1"
}

# Create a VPC for email processing
resource "google_compute_network" "vpc_network" {
  name = "vpc-email-processing"
}

# Create Subnet for VPC
resource "google_compute_subnetwork" "subnet" {
  name          = "subnet-email-processing"
  ip_cidr_range = "10.0.1.0/24"
  region        = var.region
  network       = google_compute_network.vpc_network.id
}

# Create Cloud Function for email processing (Bounce, Open Tracking, Unsubscribe)
resource "google_cloudfunctions_function" "email_function" {
  name        = "emailFunction"
  runtime     = "python39"
  available_memory_mb = 256
  entry_point = "process_email"
  source_archive_bucket = google_storage_bucket.email_function_bucket.name
  source_archive_object = "email_function.zip"
  trigger_http = true

  environment_variables = {
    GCP_PROJECT_ID = var.project_id
  }

  https_trigger_security_level = "SECURE_ALWAYS"
}

# Create Google Storage bucket for Cloud Function code
resource "google_storage_bucket" "email_function_bucket" {
  name     = "email-function-bucket-${var.project_id}"
  location = var.region
  force_destroy = true
}

3. Initialize and Apply the Terraform Configuration:
   • Run terraform init to initialize the configuration.
   • Run terraform apply to apply the infrastructure configuration and create the necessary resources.

---

Step 2: Cloudflare Setup

To manage DNS records and set up email routing through Cloudflare, follow these steps:

1. MX Records Configuration:

   • Add the MX records for your domain in Cloudflare (e.g., split.cfored.com):
     • route1.mx.cloudflare.net (Priority: 2)
     • route2.mx.cloudflare.net (Priority: 81)
     • route3.mx.cloudflare.net (Priority: 91)

2. Create Cloudflare Workers for Email Routing:
   You will use a Cloudflare Worker to route inbound emails to the Google Cloud Function for processing.

   Cloudflare Worker Script:

   addEventListener('fetch', event => {
      event.respondWith(handleRequest(event.request))
   })
   
   async function handleRequest(request) {
      // Extract email content and recipient
      const emailRecipient = extractEmailRecipient(request)
   
      // Forward email content to Google Cloud Function
      const fetchResponse = await fetch('https://REGION-PROJECT_ID.cloudfunctions.net/emailFunction', {
          method: 'POST',
          headers: { 'Content-Type': 'application/json' },
          body: JSON.stringify({ email_content: await request.text() })
      })
      return new Response(fetchResponse.body, {
          status: fetchResponse.status,
          headers: fetchResponse.headers
      })
   }
   
   function extractEmailRecipient(request) {
      const emailHeaders = request.headers.get('To')
      return emailHeaders
   }

3. Configure the Worker Script in Terraform:

resource "cloudflare_worker_script" "email_worker" {
  name = "workers-n8n-4"
  content = file("${path.module}/cloudflare_worker_script.js")
}

resource "cloudflare_worker_route" "email_route" {
  zone_id     = "your-cloudflare-zone-id"
  pattern     = "*.split.cfored.com/*"
  script_name = cloudflare_worker_script.email_worker.name
}

4. Run the Terraform Script:
   • Run terraform init to initialize the worker configuration.
   • Run terraform apply to deploy the Cloudflare worker.

---

Step 3: Python Code for Email Management

3.1 Bounce Management Using IMAP

We use IMAP to monitor bounced emails and log them into Firestore/MongoDB.

Install Required Libraries:

pip install imaplib email

Python Script for Bounce Management:

import imaplib
import email
from email.header import decode_header
from pymongo import MongoClient

# MongoDB setup
client = MongoClient("mongodb+srv://your-mongo-connection-string")
db = client.email_management

# IMAP server configuration
imap_server = "imap.example.com"
email_user = "you@example.com"
email_pass = "yourpassword"

# Connect to the server
mail = imaplib.IMAP4_SSL(imap_server)
mail.login(email_user, email_pass)
mail.select("inbox")

# Search for bounce emails
status, messages = mail.search(None, '(FROM "mailer-daemon@example.com")')
mail_ids = messages[0].split()

for mail_id in mail_ids:
    status, msg_data = mail.fetch(mail_id, "(RFC822)")
    for response_part in msg_data:
        if isinstance(response_part, tuple):
            msg = email.message_from_bytes(response_part[1])
            subject, encoding = decode_header(msg["Subject"])[0]
            if isinstance(subject, bytes):
                subject = subject.decode(encoding)
            body = msg.get_payload(decode=True)
            db.bounces.insert_one({"subject": subject, "body": body})

mail.logout()

---

3.2 Email Open Tracking (Pixel Tracking)

Python Code for Sending Emails with a Tracking Pixel:

import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

def send_email_with_tracking(to_email):
    from_email = "you@example.com"
    subject = "Your Subject Here"

    msg = MIMEMultipart("alternative")
    msg["From"] = from_email
    msg["To"] = to_email
    msg["Subject"] = subject

    html_body = """
    <html>
    <body>
        <p>Hello,</p>
        <p>This email includes an embedded tracking pixel.</p>
        <img src="https://yourserver.com/tracking_pixel?email={}" width="1" height="1" />
    </body>
    </html>
    """.format(to_email)

    part = MIMEText(html_body, "html")
    msg.attach(part)

    with smtplib.SMTP("smtp.example.com", 587) as server:
        server.starttls()
        server.login("you@example.com", "yourpassword")
        server.sendmail(from_email, to_email, msg.as_string())

Server-Side Code for Tracking Pixel Handling:

from flask import Flask, request

app = Flask(__name__)

@app.route("/tracking_pixel", methods=["GET"])
def track_open():
    email = request.args.get("email")
    # Log email open
    print(f"Email opened by: {email}")
    return "", 200, {'Content-Type': 'image/gif'}

if __name__ == "__main__":
    app.run(debug=True)

---

3.3 Unsubscribe Management

Python Code for Unsubscribe Link:

def send_email_with_unsubscribe(to_email, unsubscribe_link):
    from_email = "you@example.com"
    subject = "Unsubscribe Option"

    msg = MIMEMultipart("alternative")
    msg["From"] = from_email
    msg["To"] = to_email
    msg["Subject"] = subject

    html_body = """
    <html>
    <body>
        <p>If you wish to unsubscribe, click <a href="{}">here</a>.</p>
    </body>
    </html>
    """.format(unsubscribe_link)

    part = MIMEText(html_body, "html")
    msg.attach(part)

    with smtplib.SMTP("smtp.example.com", 587) as server:
        server.starttls()
        server.login("you@example.com", "yourpassword")
        server.sendmail(from_email, to_email, msg.as_string())

unsubscribe_link = "https://yourserver.com/unsubscribe?email=recipient@example.com"
send_email_with_unsubscribe("recipient@example.com", unsubscribe_link)

Server-Side Code for Unsubscribe Handling:

@app.route("/unsubscribe", methods=["GET"])
def unsubscribe():
    email = request.args.get("email")

[DevCEDTeam]

Continuing from where we left off:

---

Step 3.3 (continued): Unsubscribe Management

Server-Side Code for Unsubscribe Handling (continued):

@app.route("/unsubscribe", methods=["GET"])
def unsubscribe():
    email = request.args.get("email")
    # Remove the email from the mailing list or mark it as unsubscribed in the database
    print(f"Unsubscribed email: {email}")
    # Optionally, store this information in your database
    # db.unsubscribes.insert_one({"email": email, "status": "unsubscribed"})
    return "You have been unsubscribed successfully.", 200

if __name__ == "__main__":
    app.run(debug=True)

Explanation:

• send_email_with_unsubscribe(): Sends an email with an unsubscribe link. When the user clicks the link, it directs them to the server, which processes the unsubscribe action.
• unsubscribe() route: Handles requests from users clicking the unsubscribe link and marks them as unsubscribed in the system. This action is usually logged in your database (MongoDB or Firestore).

---

Step 4: Testing and Monitoring the System

To ensure everything works as expected, follow these testing steps:

4.1 Testing Bounce Management

1. Send emails to invalid or non-existing email addresses.
2. Run the IMAP script (bounce tracking) to monitor and capture bounced emails.
3. Verify that bounced emails are logged in Firestore/MongoDB.

4.2 Testing Email Open Tracking

1. Send emails to valid addresses using the send_email_with_tracking() function.
2. Open the email in the recipient inbox.
3. Check your server logs to confirm that the tracking pixel has been requested and the email open event is logged.

4.3 Testing Unsubscribe Management

1. Send emails to valid addresses with the send_email_with_unsubscribe() function.
2. Click the unsubscribe link in the email.
3. Check your server to ensure that the user has been unsubscribed successfully.

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Summary of Key Steps

1. Infrastructure Setup:

   • Use Terraform to configure Google Cloud infrastructure, Cloud Functions, and Firestore/MongoDB.
   • Set up MX Records and Cloudflare Workers to handle email routing through your domain.

2. Email Management via Python:

   • Bounce Management: Monitor bounced emails using IMAP and store logs in Firestore/MongoDB.
   • Email Open Tracking: Track email opens by embedding a tracking pixel and logging events when the pixel is loaded.
   • Unsubscribe Management: Provide users with unsubscribe links and process their requests via Flask server routes.

3. Testing and Verification:

   • Test each part of the system to ensure that bounce management, email open tracking, and unsubscribe handling work correctly.

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Next Steps

Once the system is in place and working, you can:

• Expand your Database: Track additional metadata (such as bounce reasons, unsubscribe times, etc.) and generate reports based on user activity.
• Automate Responses: Implement automatic responses for bounced emails or provide confirmation emails after a user unsubscribes.
• Enhance Security: Secure your infrastructure by setting up HTTPS for your webhook endpoints and ensuring all interactions are encrypted.

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With these steps, you should now have a robust email management system deployed using open-source tools, Python, Google Cloud, and Cloudflare. Let me know if you need further assistance or adjustments!