2014/1/22 Anders Ingemann <[email protected]> > On 22 January 2014 08:23, olivier sallou <[email protected]> wrote: > >> >> >> >> 2014/1/22 Jimmy Kaplowitz <[email protected]> >> >>> Neat. Yeah, a GCE image is simply a raw bootable disk named disk.raw, >>> compressed in a gzipped GNU-format tarball with a filename ending in >>> .tar.gz. We also encourage creating disk.raw as a sparse file and using GNU >>> tar's S flag to minimize image size and add time. The tarball is necessary >>> but hopefully the code is general enough to handle that. Certain bits of >>> our image snapshotting tool gcimagebundle expect everything aside from the >>> bootloader to be in a single MSDOS partition number 1. >>> >> I think this is the case for virtualbox provider. >> >>> We make various tweaks, such as installing the various integration >>> software I've mentioned before, pointing to our Debian mirror, and (with >>> Tomasz's pull request into the google GitHub fork) the host machine's NTP >>> server, etc. Nothing that changes the essence. >>> >> Some of those (setting up a mirror, installing packages) can be done: >> 1) with plugins (but as it is a requirement for you this is not the best >> choice) >> 2) in your plugin task, use the library part that manage package install >> etc.. if you look at cloud-init plugin task for example, you will see how >> to add a source (here debian backports) and packages to the image (here >> "sudo"). >> >> The rest of the plugin task can focus on copying some files in the image, >> setting ntp etc... >> >>> The strategy you suggest sounds worth trying indeed. >>> >>> - Jimmy >>> On Jan 21, 2014 10:32 PM, "olivier sallou" <[email protected]> >>> wrote: >>> >>>> >>>> >>>> >>>> 2014/1/21 Tomasz Rybak <[email protected]> >>>> >>>>> As Jimmy wrote in his email from 2014-01-14, I started >>>>> looking at GCE-related parts of build-debian-cloud. >>>>> >>>>> I assume that the course for now is changing the scripts >>>>> to work in Python, similar to what's being done with EC2 >>>>> and VirtualBox parts. Should we branch from andsens/python >>>>> and work on it, or do something else? Also, who'll create >>>>> the main branch (GCE-python-WIP?), into which we would >>>>> pull proposed changes? I think the best solution would be >>>>> to create such branch in repository >>>>> https://github.com/google/build-debian-cloud >>>>> >>>>> As for the work to do, I think we'll need to: >>>>> 1. change gce file to proper manifest >>>>> 2. move tasks from tasks/gce to providers/gce and >>>>> rewrite them in Python >>>>> 3. integrate cloud-init when appropriate >>>>> >>>> >>>> If the base image requirement is a raw image file and GCE only adds >>>> startup/management scripts for boot etc... you may only develop a plugin >>>> and use VirtualBox provider which is in fact a quite generic one (not only >>>> virtualbox). >>>> >>>> I personnaly use VirtualBox provider for my KVM machines and use the >>>> opennebula plugin for the OpenNebula contextualization (will be modified >>>> soon to use cloud-init too). >>>> >>>> Then, for GCE, it would be, for the user, only a matter of user >>>> VirtualBox provider (raw format) and activating the GCE plugin. >>>> >>>> Olivier >>>> >>>> >>>> >>>> >>>> >>>>> This is rough idea, and I have not touched >>>>> packaging of >>>>> https://github.com/GoogleCloudPlatform/compute-image-packages >>>>> >>>>> Have I missed something? I assume we need to have >>>>> more detailed plan of moving to Python so anyone >>>>> can see what is to be done and volunteer to some >>>>> tasks ;-) For now I just want to start discussion >>>>> to see what I forgot about. >>>>> >>>>> Best regards. >>>>> >>>>> -- >>>>> Tomasz Rybak GPG/PGP key ID: 2AD5 9860 >>>>> Fingerprint A481 824E 7DD3 9C0E C40A 488E C654 FB33 2AD5 9860 >>>>> http://member.acm.org/~tomaszrybak >>>>> >>>>> >>>> >>>> >>>> -- >>>> >>>> gpg key id: 4096R/326D8438 (keyring.debian.org) >>>> >>>> Key fingerprint = 5FB4 6F83 D3B9 5204 6335 D26D 78DC 68DB 326D 8438 >>>> >>>> >> >> >> -- >> >> gpg key id: 4096R/326D8438 (keyring.debian.org) >> >> Key fingerprint = 5FB4 6F83 D3B9 5204 6335 D26D 78DC 68DB 326D 8438 >> >> Heh, it's great to see others are able to figure out my framework > already, without documentation. I should really get on with writing it > though... :-) > > > If the base image requirement is a raw image file and GCE only adds > startup/management scripts for boot etc... you may only develop a plugin > and use VirtualBox provider which is in fact a quite generic one (not only > virtualbox). > > I would strongly suggest to refrain from doing that. If the VirtualBox > provider is indeed very generic, things should be abstracted into task > sets. I have not abstracted much of it until now, since I wasn't aware of > the commonalities between providers (given that there are only to - or > three now with kvm). If You add GCE as a separate provider, I can take a > look at it and create some new tasksets that should make the task resolving > a bit easier. >
So, do you think we should create a KVM provider ? (which would be 99% equivalent to VirtualBox for the moment but would preserve from virtualbox modifications) Olivier > > The advantages of having a provider rather than a plugin are manifold. > > 1. Plugins tasks will be resolved *after* the provider tasks, meaning > they will be able to remove some provider tasks if they do something more > specific. > 2. You can enforce plugin compatibility in the manifest schemas by > looking at the provider string, having a plugin look at what other plugins > are loaded is just messy. > > Disadvantages of creating a provider as a plugin: > > 1. Any changes you make because the virtualbox provider doesn't quite > fit will become hard to understand - one provider adding a task and the > plugin removing that same task... you might end up with a tasklist that is > completely different from virtualbox (once you are done). > 2. Changes to the virtualbox provider will now have to be carefully > made because other providers suddenly rely on it > 3. You will have a hard time adding special things to the manifest > since the vbox provider applies its own manifest schema > > > In your plugin task, use the library part that manage package install > etc.. if you look at cloud-init plugin task for example, you will see how > to add a source (here debian backports) and packages to the image (here > "sudo"). > What he said! The package API can save you a lot of trouble. Btw, you can > add trusted keyrings to apt through the manifest as well. > > Anders > > -- gpg key id: 4096R/326D8438 (keyring.debian.org) Key fingerprint = 5FB4 6F83 D3B9 5204 6335 D26D 78DC 68DB 326D 8438
