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Diffstat (limited to 'cloudinit/config/cc_snappy.py')
| -rw-r--r-- | cloudinit/config/cc_snappy.py | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/cloudinit/config/cc_snappy.py b/cloudinit/config/cc_snappy.py new file mode 100644 index 00000000..fa9d54a0 --- /dev/null +++ b/cloudinit/config/cc_snappy.py @@ -0,0 +1,304 @@ +# vi: ts=4 expandtab +# +""" +snappy modules allows configuration of snappy. +Example config: + #cloud-config + snappy: + system_snappy: auto + ssh_enabled: auto + packages: [etcd, pkg2.smoser] + config: + pkgname: + key2: value2 + pkg2: + key1: value1 + packages_dir: '/writable/user-data/cloud-init/snaps' + + - ssh_enabled: + This controls the system's ssh service. The default value is 'auto'. + True: enable ssh service + False: disable ssh service + auto: enable ssh service if either ssh keys have been provided + or user has requested password authentication (ssh_pwauth). + + - snap installation and config + The above would install 'etcd', and then install 'pkg2.smoser' with a + '<config-file>' argument where 'config-file' has 'config-blob' inside it. + If 'pkgname' is installed already, then 'snappy config pkgname <file>' + will be called where 'file' has 'pkgname-config-blob' as its content. + + Entries in 'config' can be namespaced or non-namespaced for a package. + In either case, the config provided to snappy command is non-namespaced. + The package name is provided as it appears. + + If 'packages_dir' has files in it that end in '.snap', then they are + installed. Given 3 files: + <packages_dir>/foo.snap + <packages_dir>/foo.config + <packages_dir>/bar.snap + cloud-init will invoke: + snappy install <packages_dir>/foo.snap <packages_dir>/foo.config + snappy install <packages_dir>/bar.snap + + Note, that if provided a 'config' entry for 'ubuntu-core', then + cloud-init will invoke: snappy config ubuntu-core <config> + Allowing you to configure ubuntu-core in this way. +""" + +from cloudinit import log as logging +from cloudinit import util +from cloudinit.settings import PER_INSTANCE + +import glob +import tempfile +import os + +LOG = logging.getLogger(__name__) + +frequency = PER_INSTANCE +SNAPPY_CMD = "snappy" +NAMESPACE_DELIM = '.' + +BUILTIN_CFG = { + 'packages': [], + 'packages_dir': '/writable/user-data/cloud-init/snaps', + 'ssh_enabled': "auto", + 'system_snappy': "auto", + 'config': {}, +} + + +def parse_filename(fname): + fname = os.path.basename(fname) + fname_noext = fname.rpartition(".")[0] + name = fname_noext.partition("_")[0] + shortname = name.partition(".")[0] + return(name, shortname, fname_noext) + + +def get_fs_package_ops(fspath): + if not fspath: + return [] + ops = [] + for snapfile in sorted(glob.glob(os.path.sep.join([fspath, '*.snap']))): + (name, shortname, fname_noext) = parse_filename(snapfile) + cfg = None + for cand in (fname_noext, name, shortname): + fpcand = os.path.sep.join([fspath, cand]) + ".config" + if os.path.isfile(fpcand): + cfg = fpcand + break + ops.append(makeop('install', name, config=None, + path=snapfile, cfgfile=cfg)) + return ops + + +def makeop(op, name, config=None, path=None, cfgfile=None): + return({'op': op, 'name': name, 'config': config, 'path': path, + 'cfgfile': cfgfile}) + + +def get_package_config(configs, name): + # load the package's config from the configs dict. + # prefer full-name entry (config-example.canonical) + # over short name entry (config-example) + if name in configs: + return configs[name] + return configs.get(name.partition(NAMESPACE_DELIM)[0]) + + +def get_package_ops(packages, configs, installed=None, fspath=None): + # get the install an config operations that should be done + if installed is None: + installed = read_installed_packages() + short_installed = [p.partition(NAMESPACE_DELIM)[0] for p in installed] + + if not packages: + packages = [] + if not configs: + configs = {} + + ops = [] + ops += get_fs_package_ops(fspath) + + for name in packages: + ops.append(makeop('install', name, get_package_config(configs, name))) + + to_install = [f['name'] for f in ops] + short_to_install = [f['name'].partition(NAMESPACE_DELIM)[0] for f in ops] + + for name in configs: + if name in to_install: + continue + shortname = name.partition(NAMESPACE_DELIM)[0] + if shortname in short_to_install: + continue + if name in installed or shortname in short_installed: + ops.append(makeop('config', name, + config=get_package_config(configs, name))) + + # prefer config entries to filepath entries + for op in ops: + if op['op'] != 'install' or not op['cfgfile']: + continue + name = op['name'] + fromcfg = get_package_config(configs, op['name']) + if fromcfg: + LOG.debug("preferring configs[%(name)s] over '%(cfgfile)s'", op) + op['cfgfile'] = None + op['config'] = fromcfg + + return ops + + +def render_snap_op(op, name, path=None, cfgfile=None, config=None): + if op not in ('install', 'config'): + raise ValueError("cannot render op '%s'" % op) + + shortname = name.partition(NAMESPACE_DELIM)[0] + try: + cfg_tmpf = None + if config is not None: + # input to 'snappy config packagename' must have nested data. odd. + # config: + # packagename: + # config + # Note, however, we do not touch config files on disk. + nested_cfg = {'config': {shortname: config}} + (fd, cfg_tmpf) = tempfile.mkstemp() + os.write(fd, util.yaml_dumps(nested_cfg).encode()) + os.close(fd) + cfgfile = cfg_tmpf + + cmd = [SNAPPY_CMD, op] + if op == 'install': + if path: + cmd.append("--allow-unauthenticated") + cmd.append(path) + else: + cmd.append(name) + if cfgfile: + cmd.append(cfgfile) + elif op == 'config': + cmd += [name, cfgfile] + + util.subp(cmd) + + finally: + if cfg_tmpf: + os.unlink(cfg_tmpf) + + +def read_installed_packages(): + ret = [] + for (name, date, version, dev) in read_pkg_data(): + if dev: + ret.append(NAMESPACE_DELIM.join([name, dev])) + else: + ret.append(name) + return ret + + +def read_pkg_data(): + out, err = util.subp([SNAPPY_CMD, "list"]) + pkg_data = [] + for line in out.splitlines()[1:]: + toks = line.split(sep=None, maxsplit=3) + if len(toks) == 3: + (name, date, version) = toks + dev = None + else: + (name, date, version, dev) = toks + pkg_data.append((name, date, version, dev,)) + return pkg_data + + +def disable_enable_ssh(enabled): + LOG.debug("setting enablement of ssh to: %s", enabled) + # do something here that would enable or disable + not_to_be_run = "/etc/ssh/sshd_not_to_be_run" + if enabled: + util.del_file(not_to_be_run) + # this is an indempotent operation + util.subp(["systemctl", "start", "ssh"]) + else: + # this is an indempotent operation + util.subp(["systemctl", "stop", "ssh"]) + util.write_file(not_to_be_run, "cloud-init\n") + + +def system_is_snappy(): + # channel.ini is configparser loadable. + # snappy will move to using /etc/system-image/config.d/*.ini + # this is certainly not a perfect test, but good enough for now. + content = util.load_file("/etc/system-image/channel.ini", quiet=True) + if 'ubuntu-core' in content.lower(): + return True + if os.path.isdir("/etc/system-image/config.d/"): + return True + return False + + +def set_snappy_command(): + global SNAPPY_CMD + if util.which("snappy-go"): + SNAPPY_CMD = "snappy-go" + else: + SNAPPY_CMD = "snappy" + LOG.debug("snappy command is '%s'", SNAPPY_CMD) + + +def handle(name, cfg, cloud, log, args): + cfgin = cfg.get('snappy') + if not cfgin: + cfgin = {} + mycfg = util.mergemanydict([cfgin, BUILTIN_CFG]) + + sys_snappy = str(mycfg.get("system_snappy", "auto")) + if util.is_false(sys_snappy): + LOG.debug("%s: System is not snappy. disabling", name) + return + + if sys_snappy.lower() == "auto" and not(system_is_snappy()): + LOG.debug("%s: 'auto' mode, and system not snappy", name) + return + + set_snappy_command() + + pkg_ops = get_package_ops(packages=mycfg['packages'], + configs=mycfg['config'], + fspath=mycfg['packages_dir']) + + fails = [] + for pkg_op in pkg_ops: + try: + render_snap_op(**pkg_op) + except Exception as e: + fails.append((pkg_op, e,)) + LOG.warn("'%s' failed for '%s': %s", + pkg_op['op'], pkg_op['name'], e) + + # Default to disabling SSH + ssh_enabled = mycfg.get('ssh_enabled', "auto") + + # If the user has not explicitly enabled or disabled SSH, then enable it + # when password SSH authentication is requested or there are SSH keys + if ssh_enabled == "auto": + user_ssh_keys = cloud.get_public_ssh_keys() or None + password_auth_enabled = cfg.get('ssh_pwauth', False) + if user_ssh_keys: + LOG.debug("Enabling SSH, ssh keys found in datasource") + ssh_enabled = True + elif cfg.get('ssh_authorized_keys'): + LOG.debug("Enabling SSH, ssh keys found in config") + elif password_auth_enabled: + LOG.debug("Enabling SSH, password authentication requested") + ssh_enabled = True + elif ssh_enabled not in (True, False): + LOG.warn("Unknown value '%s' in ssh_enabled", ssh_enabled) + + disable_enable_ssh(ssh_enabled) + + if fails: + raise Exception("failed to install/configure snaps") |