Re: [libvirt] [sandbox 08/11] virt-sandbox-image: add a virt-builder source

Allow virt-sandbox-image to pull templates from virt-builder and run sandboxes on top of them. --- libvirt-sandbox.spec.in | 1 + libvirt-sandbox/image/cli.py | 1 + libvirt-sandbox/image/sources/Makefile.am | 1 + libvirt-sandbox/image/sources/VirtBuilderSource.py | 136 +++++++++++++++++++++ libvirt-sandbox/image/template.py | 2 + 5 files changed, 141 insertions(+) create mode 100644 libvirt-sandbox/image/sources/VirtBuilderSource.py

+class VirtBuilderSource(Source): + + def _get_template_name(self, template): + # We shouldn't have '/' in the names, but let's make sure + # nobody can try to alter the folders structure later. + return template.path[1:].replace('/', '_') + + def download_template(self, template, templatedir): + # We don't do anything here: virt-builder will do it for us in + # the create action + pass

+ + def _check_disk_format(self,format): + supportedFormats = ['qcow2', 'raw'] + if not format in supportedFormats: + raise ValueError(["Unsupported image format %s" % format]) + + def create_template(self, template, templatedir, + connect=None, format=None): + # FIXME Force qcow2 format: do we really want people to mess with that? + if not os.path.exists(templatedir): + os.makedirs(templatedir) + + # Get the image using virt-builder + templatename = self._get_template_name(template) + imagepath_original = "%s/%s-original.qcow2" % (templatedir, templatename) + imagepath = "%s/%s.%s" % (templatedir, templatename, format) + cmd = ["virt-builder", templatename, + "-o", imagepath_original, "--format", "qcow2"] + subprocess.call(cmd)

+ + # We need to convert this image into a single partition one. + tarfile = "%s/%s.tar" % (templatedir, templatename) + cmd = ["virt-tar-out", "-a", imagepath_original, "/", tarfile] + subprocess.call(cmd) + + os.unlink(imagepath_original) + + cmd = ["qemu-img", "create", "-q", "-f", format, imagepath, "10G"] + subprocess.call(cmd) + + self.format_disk(imagepath, format, connect) + self._extract_tarball(imagepath, format, tarfile, connect) + os.unlink(tarfile) + + + def delete_template(self, template, templatedir): + # Check for running sandboxes using this template before killing it + images = self._get_template_uses(template, templatedir) + if len(images) != 0: + imagesStr = ", ".join(images) + raise ValueError(["Images still using the template: %s" % imagesStr]) + + os.unlink("%s/%s.qcow2" % (templatedir, self._get_template_name(template))) + os.unlink("%s/%s.uses" % (templatedir, self._get_template_name(template))) + + def _get_template_uses(self, template, templatedir): + uses = open("%s/%s.uses" % (templatedir, self._get_template_name(template)), "r") + lines = uses.read() + uses.close() + return [l for l in lines.split("\n") if l != ""] + + def post_run(self, template, templatedir, imagename): + images = self._get_template_uses(template, templatedir) + images.remove(imagename) + + uses = open("%s/%s.uses" % (templatedir, self._get_template_name(template)), "w") + uses.write("\n".join(images)) + uses.close() + + def get_command(self, template, templatedir, userargs): + return userargs + + def get_disk(self,template, templatedir, imagedir, sandboxname): + diskfile = "%s/%s.qcow2" % (templatedir, self._get_template_name(template)) + tempfile = imagedir + "/" + sandboxname + ".qcow2" + if not os.path.exists(imagedir): + os.makedirs(imagedir) + cmd = ["qemu-img", "create", "-q", + "-f", "qcow2", + "-o", "backing_fmt=qcow2,backing_file=%s" % diskfile, + tempfile] + subprocess.call(cmd) + + # Add the image to the uses files + uses = open("%s/%s.uses" % (templatedir, + self._get_template_name(template)), "a") + uses.write("%s\n" % sandboxname) + uses.close()

+ return tempfile + + def get_env(self,template, templatedir): + return [] + + def _extract_tarball(self, diskfile, format, tarfile, connect): + cmd = ['virt-sandbox'] + if connect is not None: + cmd.append("-c") + cmd.append(connect) + cmd.append("-p") + params = ['-m', + 'host-image:/mnt=%s,format=%s' % (diskfile, format), + '--', + '/bin/tar', + 'xf', + '%s' % tarfile, + '-C', + '/mnt'] + cmd = cmd + params + subprocess.call(cmd)