About smtp2web

What is smtp2web?

smtp2web is a service to make it easier for web apps to receive email. It provides a set of MX (Mail eXchange) servers which accept emails for your address or entire domain, and sends them via HTTP POST to your servers.

Why would I want to use it?

Some web apps, such as Google App Engine apps, are unable to receive emails directly, as they can only serve up HTTP requests. Even if your app runs in an environment that supports running a custom SMTP server, using smtp2web may be much simpler than setting up your own mail exchange infrastructure.

How does it work?

Whenever an email arrives for an address or domain assigned to you, the entire message (including headers) is sent in a POST request to the URL you specified, with Content-Type: multipart/rfc-822. In addition, the query parameters "from" and "to" are set to the envelope sender and recipient, respectively.

Here's how to use it in an App Engine application, when using App Engine's webapp framework:

from google.appengine.ext import webapp
import email

class EmailHandler(webapp.RequestHandler):
  def post(self):
    sender = self.request.GET.get("from", "")
    recipient = self.request.GET.get("to", "")
    message = email.message_from_string(self.request.body)
    # Do stuff with the email message

How much does it cost?

Nothing. In time, a paid option for heavy use may be introduced, but there will always be a reasonable "free quota".

How many emails can I receive per day?

There's no firm limit, but keep it reasonable. In case of excessive use (excessive being to the point that it impairs others' use of the facilities), we reserve the right to disable or limit your account. We will always attempt to contact you before doing that, however.

Do you support other interfaces, such as SOAP or XML-RPC?

No, but it's planned. If you need or really, really want such an interface, let me know by emailing arachnid AT notdot.net and tell me about it!

What if I just want a single email address?

That's fine - just sign in, go to the main page, and select "add @smtp2web.com mapping". You can then pick an smtp2web.com email address and a URL to send messages to.

What if I want all the email for my domain to use the service?

That's fine too! Just choose "add domain mapping" on the main page and specify the domain and URL. Once you've finished the process, you'll be provided with a list of MX records you should configure on your domain to enable the service.

What if I want only some of my domain's email to use the service?

We don't support this directly - all the mail sent to our MX servers is either POSTed to a URL or rejected. However, if you register a single @smtp2web.com address and configure your own mail system to forward email for the required addresses to it, you can achieve the same effect.

Is the source available?

Yes. smtp2web is licensed under the Apache License, and is available here, on Google Code.

My question isn't covered here, or I have a suggestion or problem

Sure! Email me at arachnid AT notdot.net with your complaints, questions or suggestions.