Self-Hosted Email Tracker

This project is a lightweight email tracking system for logging opens and clicks of emails sent from Gmail (including mobile). It uses a Google Apps Script to process drafted emails and a Python FastAPI backend deployed via Docker to a Raspberry Pi (or any server).

Components

• Python FastAPI Server (Dockerized, Multi-arch for Raspberry Pi).
• SQLite Database for logging tracking data locally.
• Google Apps Script snippet for injecting tracking links/pixels into drafts.

Setup Instructions

1. Server Setup (Raspberry Pi/Linux)

1. Make sure Docker and Docker Compose are installed on your device.
   • For Ubuntu/Debian, you can install them by running:

     # Add Docker's official GPG key:
     sudo apt-get update
     sudo apt-get install -y ca-certificates curl
     sudo install -m 0755 -d /etc/apt/keyrings
     sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
     sudo chmod a+r /etc/apt/keyrings/docker.asc
     
     # Add the repository to Apt sources:
     echo \
       "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
       $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
       sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
     sudo apt-get update
     
     # Install Docker Engine
     sudo apt-get install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin
     sudo usermod -aG docker $USER

     (Log out and log back in, or run newgrp docker so your group membership is re-evaluated)
2. Clone this repository to your Raspberry Pi.
3. Open a terminal in the repository folder and run the following to create the database file and start the server:

   touch tracking.db
   docker compose up -d --build

4. The service will be running on port 8081 (you can change this in docker-compose.yml if it conflicts with another service).
5. Check if it's working by visiting http://<your-pi-ip>:8081/dashboard.
6. To make the service accessible from the outside (which is required for tracking to work), we recommend using Cloudflare Tunnels.
   • Install cloudflared on your Raspberry Pi and configure a Tunnel.
   • Permanent Tunnel with Custom Domain: Log into the Cloudflare Zero Trust Dashboard, go to Networks -> Tunnels, create a new tunnel, and follow the installation command provided to point it to http://localhost:8081.
   • Securing Your Tunnel: In the Cloudflare Zero Trust Dashboard (Access -> Applications), secure your tunnel's domain by requiring authentication (e.g., email OTP). Crucially, you must create "Bypass" rules for the /open* and /click* paths. This ensures your dashboard remains private while the tracking pixels and links remain publicly accessible.
   • Make a note of your public URL to use in the Google Apps Script setup.

2. Google Apps Script Setup

1. In your Gmail account, create a new label named TrackMe.
2. Go to script.google.com and create a new project.
3. Copy the contents of the google_apps_script.js file into the editor.
4. Update the TRACKING_SERVER_URL variable at the top of the file to your public URL from the server setup phase.
5. Save the project setup.
6. Set up a Time-driven Trigger:
   • Click the Triggers icon (the clock 🕒 on the left).
   • Click Add Trigger.
   • Choose processTrackedDrafts as the function to run.
   • Set the event source to Time-driven.
   • Set the type to Minutes timer (e.g., every 1 or 5 minutes).
   • Save the trigger. (Google might ask you to authorize the script; follow the prompts to grant permission).

Usage

1. In Gmail (desktop or your mobile app), compose a new email or a reply.
2. Save it as a Draft.
3. Apply the TrackMe label:
   • For new emails: Click the 3 dots at the bottom of the compose window -> Label -> Check TrackMe.
   • For replies: You cannot label the draft directly. Instead, apply the TrackMe label to the entire email conversation (thread) using the "Labels" icon at the top of the screen.
4. Let the Google Apps Script run (based on your timer). The script will append a tracking pixel, wrap any links for tracking, send the email automatically, and delete the draft.
5. You can view your tracking stats by visiting http://<your-public-url>/dashboard.

Database

The tracking events are logged into a local tracking.db SQLite file created inside the container and mounted via Docker Compose.

Backing up your database: If you want to back up your database to Google Drive, OneDrive, or another cloud service on your Raspberry Pi, you can change the volume mount location in docker-compose.yml. Simply change ./tracking.db to the absolute path of your sync folder (e.g., /home/pi/GoogleDrive/tracking.db).