Sunlight Foundation

I recently learned (with horror) that a co-worker wrote her blog posts in Gmail, copied the rich text to WordPress, then copy and pasted the generated HTML into our Markdown-enabled blog backend. To be fair, our nerdy authoring tool is a bit much for non-technical users and doesn't really fit into most "normal" workflows. Additionally, she emails her posts to an internal list so Gmail was a natural authoring tool.

There had to be some common ground we could find; blog posts still written in Markdown while allowing her to use Gmail to write her posts. Our solution was to enable post-by-email on the blog. By adding a special email address to the recipients, the message is parsed into Markdown, a draft post is created, and she receives an email reply a few seconds later with a link to edit the new post. From there she can review and publish it in a few clicks resulting in a much improved workflow.

We wanted the draft posts created immediately and I didn't care to be polling a mail server every few seconds. Fortunately, we found a new service that made this project incredibly easy to implement.

CloudMailin.com

CloudMailin.com is a fantastic service that does the opposite of most other mail services. Rather than providing an API based method of sending email like Postmark, another fantastic service, CloudMailin.com receives email at a provided address and POSTs the data to a URL of your choosing. In addition to the simple parsing of SMTP headers and MIME parts, the service can handle email attachments. Pay them a few bucks extra and they'll upload the attachments to one of your S3 buckets!

A competing service we evaluated started at a pricey $30 a month; a bit ridiculous if we are receiving 5 emails a week to start. CloudMailin.com's recently announced pricing is right on the mark with a 200 message free plan and a 3000 message micro plan for $9 per month.

So how did we make it work? Let's look at some code...

django-cloudmailin

django-cloudmailin is a Django app we created to make working with CloudMailin.com as simple as possible. First we need a method that will receive the posted email message parameters and create a blog post.

In create_post we extract the parameters from the message to get the author, title, and content of the post. A post object is created and an email is sent back to the original sender of the email with a link to the Django admin for the new post. The author needs to check to make sure the post looks correct and hit publish. This is a greatly simplified example because we do some additional parsing of the content to transform the plain text into valid Markdown, but it should give you an idea of how it works.

Next we register that method with the mail handler.

MailHandler is a class-based view provided by django-cloundmailin that handles the registration and processing of mail messages. In this example we register our CloudMailin.com email address and secret key with the method that is to be invoked upon receipt of a new message. Multiple email addresses can be registered with the handler to allow for many different actions-by-mail in the same application. Finally the MailHandler instance is associated with an URL pattern in urls.py.

All incoming messages are signed with your secret key to prevent any old person from spamming your mail endpoint. The MailHandler instance takes care of verifying the signature so you can concentrate on writing your application.

You can find the source for django-cloudmailin on GitHub.

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