Email Resender

A Cloudflare Worker script that acts as an email proxy. It allows you to send emails from your custom domain by simply sending a message from your personal email client to a designated forwarding address using Resend's API.

Environment variables:

You must provide the following environment variables (either in a .dev.vars file for local development or configured in your Cloudflare dashboard):

• AUTHORIZED_SENDER: The personal email address that the proxy will accept messages from (e.g., you@gmail.com). This prevents unauthorized users from sending emails through your domain.
• RESEND_API_KEY: Your API key from Resend, which is used to actually send the outgoing emails.
• EMAIL_DOMAIN: Your custom domain name (e.g., yourdomain.com).
• MAGIC_PREFIX: A special string (like @ or !) used at the beginning of lines in your email body to specify routing commands without including them in the final email.

Example

To send an email via your personal email client, draft a message to your Cloudflare Worker's routing address and use your MAGIC_PREFIX to specify the sender alias and recipient.

If your MAGIC_PREFIX is set to !, your draft might look like this:

To: worker@yourdomain.com (Your Cloudflare routing address)
Subject: Hello from my custom domain!
Body:

!from: contact@yourdomain.com
!to: customer@example.com
!cc: cc1@example.com, cc2@example.com
!bcc: bcc1@example.com, bcc2@example.com

Hi there!
This is the actual body of the email. Notice how the commands above will be stripped out so the recipient won't see them.

Deploy

Install dependencies:

npm install

Deploy to cloudflare workers (login if prompted):

npx wrangler deploy

⚠️ Note: Wrangler may experience compatibility issues with Bun or other alternative package managers. I recommend using npm and npx.

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Made with ❤️ & 🍣 by afsc19