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The From: addresses used by Launchpad’s bug notifications have changed, to improve the chances of our messages being delivered over modern internet email.

Launchpad sends a lot of email, most of which is the result of Launchpad users performing some kind of action. For example, when somebody adds a comment to a bug, Launchpad sends that comment by email to everyone who’s subscribed to the bug.

Most of Launchpad was designed in an earlier era of internet email. In that era, it was perfectly reasonable to take the attitude that we were sending email on behalf of the user – in effect, being a fancy mail user agent or perhaps a little like a mailing list – and so if we generated an email that’s a direct result of something that a user did and consisting mostly of text they wrote, it made sense to put their email address in the From: header. Reply-To: was set so that replies would normally go to the appropriate place (the bug, in the case of bug notifications), but if somebody wanted to go to a bit of effort to start a private side conversation then it was easy to do so; and if email clients had automatic address books then those wouldn’t get confused because the address being used was a legitimate address belonging to the user in question.

Of course, some people always wanted to hide their addresses for obvious privacy reasons, so since 2006 Launchpad has had a “Hide my email address from other Launchpad users” switch (which you can set on your Change your personal details page), and since 2010 Launchpad has honoured this for bug notifications, so if you have that switch set then your bug comments will be sent out as something like “From: Your Name <bug-id@bugs.launchpad.net>“. This compromise worked tolerably well for a while.

But spammers and other bad actors ruin everything, and the internet email landscape has changed. It’s reasonably common now for operators of email domains to publish DMARC policies that require emails whose From: headers are within that domain to be authenticated in some way, and this is incompatible with the older approach. As a result, it’s been getting increasingly common for Launchpad bug notifications not to be delivered because they failed these authentication checks. Regardless of how justifiable our notification-sending practices were, we have to exist within the reality of internet email as it’s actually deployed.

So, thanks to a contribution from Thomas Ward, Launchpad now sends all its bug notifications as if the user in question had the “Hide my email address from other Launchpad users” switch set: that is, they’ll all appear as something like “From: Your Name <bug-id@bugs.launchpad.net>“. Over time we expect to extend this sort of approach to the other types of email that we send, possibly with different details depending on the situation.

Please let us know if this causes any strange behaviour in your email client. We may not be able to fix all of them, depending on how they interact with DMARC’s requirements, but we’d like to be aware of what’s going on.

Users of some email clients, particularly Gmail, have long had a problem filtering mail from Launchpad effectively.  We put lots of useful information into our message headers so that heavy users of Launchpad can automatically filter email into different folders.  Unfortunately, Gmail and some other clients do not support filtering mail on arbitrary headers, only on message bodies and on certain pre-defined headers such as Subject.  Figuring out what to do about this has been tricky.  Space in the Subject line is at a premium – many clients will only show a certain number of characters at the start, and so inserting filtering tags at the start would crowd out other useful information, so we don’t want to do that; and in general we want to avoid burdening one group of users with workarounds for the benefit of another group because that doesn’t scale very well, so we had to approach this with some care.

As of our most recent code update, you’ll find a new setting on your “Change your personal details” page:

If you check “Include filtering information in email footers”, Launchpad will duplicate some information from message headers into the signature part (below the dash-dash-space line) of message bodies: any “X-Launchpad-Something: value” header will turn into a “Launchpad-Something: value” line in the footer.  Since it’s below the signature marker, it should be relatively unobtrusive, but is still searchable.  You can search or filter for these in Gmail by putting the key/value pair in double quotes, like this:

At the moment this only works for emails related to Bazaar branches, Git repositories, merge proposals, and build failures.  We intend to extend this to a few other categories soon, particularly bug mail and package upload notifications.  If you particularly need this feature to work for some other category of email sent by Launchpad, please file a bug to let us know.

If you use gmail, you should now be able to send commands to Launchpad without gpg-signing.

gmail puts a DKIM cryptographic signature on outgoing mail, which is a cryptographic signature that proves that the mail was sent by gmail and that it was sent by the purported user. We verify the signature on Launchpad and treat that mail as trusted which means, for example, that you can triage bugs over mail or vote on merge proposals. Previously you needed to GPG-sign the mail which is a bit of a hassle for gmail.

(DKIM is signed by the sending domain, not by the user, so it doesn’t inherently prove that the purported sender is the actual one. People could intentionally or unintentionally set up a server that allows intra-domain impersonation, and it’s reported to be easy to misconfigure DKIM signers so that this happens. (Consider a simple SMTP server that accepts, signs and forwards everything from 192.168/16 with no authentication.) However, in cases like gmail we can reasonably assume Google don’t allow one user to impersonate another. We can add other trusted domains on request.)

If you have gmail configured to use some other address as your From address it will still work, as long as you verify both your gmail address and your other address.

You can use email commands to interact with both bugs and code merge proposals. For instance when Launchpad sends you mail about a new bug, you can just reply

  status confirmed
  importance medium

Thanks for letting us know!

We do this using the pydkim library.

Note that you do need at least one leading space before the commands.

If you hit any bugs, let us know.

Continuing on from our earlier work of sending less but better mail and making it faster to import i18n translation templates: Launchpad will no longer send mail when it successfully imports a template. You can see in the web ui when the template was last imported, and you will still get mail if there’s a problem.

I could hardly put it better than Riddell:

Danilo asked for my reasoning. My reasoning is that pointless e-mails are a pain.

(I hope we’ll eventually have a more structured notification model, that will let you choose to see some notifications by mail and others in the web ui. One step at a time.)