CloudMailin Demo Application

A demonstration application for CloudMailin webhook processing and email responses, built with Go.

Overview

This application was built as a test harness for the CloudMailin email-to-webhook integration, mainly to test new hosting environments.

It provides:

• Real-time email webhook processing
• Live updates via WebSocket
• Automatic email response generation
• Simple web interface with Tailwind CSS
• Docker for development

The application is built to use at least version 1.23+ of Go.

Getting Started

1. Clone the repository or run the docker container within the hosting environment.
2. Make sure you've got a CloudMailin account to test with.
3. Ensure the environment variables are set:

Environment Variables

The application requires the following environment variables:

Variable	Description
PORT	The port to run the web server on
CLOUDMAILIN_FORWARD_ADDRESS	Your CloudMailin email address
CLOUDMAILIN_SMTP_URL	SMTP URL for sending replies
FROM_EMAIL	Email address to send replies from

How It Works

1. The application starts a web server that displays your CloudMailin forward address
2. When an email is received at your CloudMailin address, it triggers a webhook to /emails
3. The application processes the webhook payload and broadcasts it via WebSocket
4. The web interface updates in real-time to show the new email
5. An automatic reply is sent using the CloudMailin SMTP service

Development

The application runs in a devcontainer for vs-code / cursor etc. just open the folder and > Reopen in Container.

The application is built to use at least version 1.23+ of Go.

Docker

If you just want to build and run the docker container locally:

# Build the image
docker build -t cloudmailin-example .

# Run the container with env variables from .env file
cp .env.example .env
docker run -d -p 8080:8080 --env-file .env cloudmailin-example

OR

docker compose up --build