Launchpad news, May 2018
Saturday, June 2nd, 2018Here’s a brief changelog for this month.
Here’s a brief changelog for this month.
Once again it’s been a while since we posted a general update, so here’s a changelog-style summary of what we’ve been up to. As usual, this changelog preserves a reasonable amount of technical detail, but I’ve omitted changes that were purely internal refactoring with no externally-visible effects.
Here’s a brief changelog for this month.
Well, it’s been a while! Since we last posted a general update, the Launchpad team has become part of Canonical’s Online Services department, so some of our efforts have gone into other projects. There’s still plenty happening with Launchpad, though, and here’s a changelog-style summary of what we’ve been up to.
Launchpad has had Git-to-Bazaar code imports since 2009, along with imports from a few other systems. These form part of Launchpad’s original mission to keep track of free software, regardless of where it’s hosted. They’re also very useful for automatically building other artifacts, such as source package recipes or snap packages, from code hosted elsewhere. Unfortunately they’re quite complicated: they need to be able to do a full round-trip conversion of every revision from the other version control system, which has made it difficult to add support for Git features such as signed commits or submodules. Once one of these features is present anywhere in the history of a branch, importing it to Bazaar becomes impossible. This has been a headache for many users.
We can do better nowadays. As of last year, we have direct Git hosting support in Launchpad, and we can already build snaps and recipes straight from Git, so we can fulfil our basic goal more robustly now with a lot less code. So, Launchpad now supports Git-to-Git code imports, also known as Git mirroring. You can use this to replace many uses of Git-to-Bazaar imports (note that there’s no translations integration yet, and of course you won’t be able to branch the resulting import using bzr
).
See our Git documentation for more details.
We just rolled out a new feature for Launchpad’s Git repository hosting: Git-based merge proposals can now be linked to Launchpad bugs. This can be done manually from the web UI for the merge proposal, but normally you should just mention the Launchpad bug in the commit message of one of the commits you want to merge. The required commit message text to link to bugs #XXX and #YYY looks like this:
LP: #XXX, #YYY
This is the same form used for Launchpad bug references in debian/changelog files in source packages, and the general approach of mentioning bugs in commit messages is similar to that of various other hosting sites.
Bugs are not automatically closed when merge proposals land, because the policy for when that should happen varies from project to project: for example, projects often only close bugs when they make releases, or when their code is deployed to production sites.
Users familiar with Bazaar on Launchpad should note that the model for Git bug linking is slightly different: bugs are linked to merge proposals rather than to individual branches. This difference is mainly because individual branches within a Git repository are often much more ephemeral than Bazaar branches.
Documentation is here, along with other details of Launchpad’s Git hosting.
Here’s what the Launchpad team did in October.
If you are a member of Launchpad’s beta testers team, you can now try out webhooks for Bazaar branches and Git repositories. These can be used to set up integration with external sites for various purposes, such as running CI jobs or publishing documentation. We expect to open this up to all Launchpad users soon, but in the meantime please do file a bug against Launchpad itself if you encounter any problems.
See our webhooks documentation for more details.
Update: as of 2015-11-20, this feature is enabled for all Launchpad users.
Personal package archives on Launchpad only build for the amd64 and i386 architectures by default, which meets most people’s needs. Anyone with an e-mail address can have a PPA, so they have to be securely virtualised, but that’s been feasible on x86 for a long time. Dealing with the other architectures that Ubuntu supports (currently arm64, armhf, powerpc, and ppc64el) in a robust and scalable way has been harder. Until recently, all of those architectures were handled either by running one builder per machine on bare metal, or in some cases by running builders on a small number of manually-maintained persistent virtual machines per physical machine. Neither of those approaches scales to the level required to support PPAs, and we need to make sure that any malicious code run by a given build is strictly confined to that build. (We support virtualised armhf PPAs, but only by using qemu-user-static
in an amd64 virtual machine, which is very fragile and there are many builds that it simply can’t handle at all.)
We’ve been working with our sysadmins for several months to extend ScalingStack to non-x86 architectures, and at the start of Ubuntu’s 16.04 development cycle we were finally able to switch all ppc64el builds over to this system. Rather than four builders, we now have 30, each of which is reset to a clean virtual machine instance between each build. Since that’s more than enough to support Ubuntu’s needs, we’ve now “unrestricted” the architecture so that it can be used for PPAs as well, and PPA owners can enable it at will. To do this, visit the main web page for your PPA (which will look something like “https://launchpad.net/~<person-name>/+archive/ubuntu/<ppa-name>”) and follow the “Change details” link; you’ll see a list of checkboxes under “Processors”, and you can enable or disable any that aren’t greyed out. This also means that you can disable amd64 or i386 builds for your PPA if you want to.
We’re working to extend this to all the existing Ubuntu architectures at the moment. arm64 is up and running but we’re still making sure it’s sufficiently robust; armhf will run on arm64 guests, and just needs a kernel patch to set its uname
correctly; and powerpc builds will run in different guests on the same POWER8 compute nodes as ppc64el once we have suitable cloud images available. We’ll post further announcements when further architectures are unrestricted.
October already! As the leaves start to turn red here in the northern hemisphere, here’s a brief summary of what we did in September.