Charmed-Kubernetes/containerd/lib/charms/layer/basic.py

502 lines
18 KiB
Python

import os
import sys
import re
import shutil
from distutils.version import LooseVersion
from pkg_resources import Requirement
from glob import glob
from subprocess import check_call, check_output, CalledProcessError
from time import sleep
from charms import layer
from charms.layer.execd import execd_preinstall
def _get_subprocess_env():
env = os.environ.copy()
env['LANG'] = env.get('LANG', 'C.UTF-8')
return env
def get_series():
"""
Return series for a few known OS:es.
Tested as of 2019 november:
* centos6, centos7, rhel6.
* bionic
"""
series = ""
# Looking for content in /etc/os-release
# works for ubuntu + some centos
if os.path.isfile('/etc/os-release'):
d = {}
with open('/etc/os-release', 'r') as rel:
for l in rel:
if not re.match(r'^\s*$', l):
k, v = l.split('=')
d[k.strip()] = v.strip().replace('"', '')
series = "{ID}{VERSION_ID}".format(**d)
# Looking for content in /etc/redhat-release
# works for redhat enterprise systems
elif os.path.isfile('/etc/redhat-release'):
with open('/etc/redhat-release', 'r') as redhatlsb:
# CentOS Linux release 7.7.1908 (Core)
line = redhatlsb.readline()
release = int(line.split("release")[1].split()[0][0])
series = "centos" + str(release)
# Looking for content in /etc/lsb-release
# works for ubuntu
elif os.path.isfile('/etc/lsb-release'):
d = {}
with open('/etc/lsb-release', 'r') as lsb:
for l in lsb:
k, v = l.split('=')
d[k.strip()] = v.strip()
series = d['DISTRIB_CODENAME']
# This is what happens if we cant figure out the OS.
else:
series = "unknown"
return series
def bootstrap_charm_deps():
"""
Set up the base charm dependencies so that the reactive system can run.
"""
# execd must happen first, before any attempt to install packages or
# access the network, because sites use this hook to do bespoke
# configuration and install secrets so the rest of this bootstrap
# and the charm itself can actually succeed. This call does nothing
# unless the operator has created and populated $JUJU_CHARM_DIR/exec.d.
execd_preinstall()
# ensure that $JUJU_CHARM_DIR/bin is on the path, for helper scripts
series = get_series()
# OMG?! is build-essentials needed?
ubuntu_packages = ['python3-pip',
'python3-setuptools',
'python3-yaml',
'python3-dev',
'python3-wheel',
'build-essential']
# I'm not going to "yum group info "Development Tools"
# omitting above madness
centos_packages = ['python3-pip',
'python3-setuptools',
'python3-devel',
'python3-wheel']
packages_needed = []
if 'centos' in series:
packages_needed = centos_packages
else:
packages_needed = ubuntu_packages
charm_dir = os.environ['JUJU_CHARM_DIR']
os.environ['PATH'] += ':%s' % os.path.join(charm_dir, 'bin')
venv = os.path.abspath('../.venv')
vbin = os.path.join(venv, 'bin')
vpip = os.path.join(vbin, 'pip')
vpy = os.path.join(vbin, 'python')
hook_name = os.path.basename(sys.argv[0])
is_bootstrapped = os.path.exists('wheelhouse/.bootstrapped')
is_charm_upgrade = hook_name == 'upgrade-charm'
is_series_upgrade = hook_name == 'post-series-upgrade'
is_post_upgrade = os.path.exists('wheelhouse/.upgraded')
is_upgrade = (not is_post_upgrade and
(is_charm_upgrade or is_series_upgrade))
if is_bootstrapped and not is_upgrade:
# older subordinates might have downgraded charm-env, so we should
# restore it if necessary
install_or_update_charm_env()
activate_venv()
# the .upgrade file prevents us from getting stuck in a loop
# when re-execing to activate the venv; at this point, we've
# activated the venv, so it's safe to clear it
if is_post_upgrade:
os.unlink('wheelhouse/.upgraded')
return
if os.path.exists(venv):
try:
# focal installs or upgrades prior to PR 160 could leave the venv
# in a broken state which would prevent subsequent charm upgrades
_load_installed_versions(vpip)
except CalledProcessError:
is_broken_venv = True
else:
is_broken_venv = False
if is_upgrade or is_broken_venv:
# All upgrades should do a full clear of the venv, rather than
# just updating it, to bring in updates to Python itself
shutil.rmtree(venv)
if is_upgrade:
if os.path.exists('wheelhouse/.bootstrapped'):
os.unlink('wheelhouse/.bootstrapped')
# bootstrap wheelhouse
if os.path.exists('wheelhouse'):
pre_eoan = series in ('ubuntu12.04', 'precise',
'ubuntu14.04', 'trusty',
'ubuntu16.04', 'xenial',
'ubuntu18.04', 'bionic')
pydistutils_lines = [
"[easy_install]\n",
"find_links = file://{}/wheelhouse/\n".format(charm_dir),
"no_index=True\n",
"index_url=\n", # deliberately nothing here; disables it.
]
if pre_eoan:
pydistutils_lines.append("allow_hosts = ''\n")
with open('/root/.pydistutils.cfg', 'w') as fp:
# make sure that easy_install also only uses the wheelhouse
# (see https://github.com/pypa/pip/issues/410)
fp.writelines(pydistutils_lines)
if 'centos' in series:
yum_install(packages_needed)
else:
apt_install(packages_needed)
from charms.layer import options
cfg = options.get('basic')
# include packages defined in layer.yaml
if 'centos' in series:
yum_install(cfg.get('packages', []))
else:
apt_install(cfg.get('packages', []))
# if we're using a venv, set it up
if cfg.get('use_venv'):
if not os.path.exists(venv):
series = get_series()
if series in ('ubuntu12.04', 'precise',
'ubuntu14.04', 'trusty'):
apt_install(['python-virtualenv'])
elif 'centos' in series:
yum_install(['python-virtualenv'])
else:
apt_install(['virtualenv'])
cmd = ['virtualenv', '-ppython3', '--never-download', venv]
if cfg.get('include_system_packages'):
cmd.append('--system-site-packages')
check_call(cmd, env=_get_subprocess_env())
os.environ['PATH'] = ':'.join([vbin, os.environ['PATH']])
pip = vpip
else:
pip = 'pip3'
# save a copy of system pip to prevent `pip3 install -U pip`
# from changing it
if os.path.exists('/usr/bin/pip'):
shutil.copy2('/usr/bin/pip', '/usr/bin/pip.save')
pre_install_pkgs = ['pip', 'setuptools', 'setuptools-scm']
# we bundle these packages to work around bugs in older versions (such
# as https://github.com/pypa/pip/issues/56), but if the system already
# provided a newer version, downgrading it can cause other problems
_update_if_newer(pip, pre_install_pkgs)
# install the rest of the wheelhouse deps (extract the pkg names into
# a set so that we can ignore the pre-install packages and let pip
# choose the best version in case there are multiple from layer
# conflicts)
_versions = _load_wheelhouse_versions()
_pkgs = _versions.keys() - set(pre_install_pkgs)
# add back the versions such that each package in pkgs is
# <package_name>==<version>.
# This ensures that pip 20.3.4+ will install the packages from the
# wheelhouse without (erroneously) flagging an error.
pkgs = _add_back_versions(_pkgs, _versions)
reinstall_flag = '--force-reinstall'
if not cfg.get('use_venv', True) and pre_eoan:
reinstall_flag = '--ignore-installed'
check_call([pip, 'install', '-U', reinstall_flag, '--no-index',
'--no-cache-dir', '-f', 'wheelhouse'] + list(pkgs),
env=_get_subprocess_env())
# re-enable installation from pypi
os.remove('/root/.pydistutils.cfg')
# install pyyaml for centos7, since, unlike the ubuntu image, the
# default image for centos doesn't include pyyaml; see the discussion:
# https://discourse.jujucharms.com/t/charms-for-centos-lets-begin
if 'centos' in series:
check_call([pip, 'install', '-U', 'pyyaml'],
env=_get_subprocess_env())
# install python packages from layer options
if cfg.get('python_packages'):
check_call([pip, 'install', '-U'] + cfg.get('python_packages'),
env=_get_subprocess_env())
if not cfg.get('use_venv'):
# restore system pip to prevent `pip3 install -U pip`
# from changing it
if os.path.exists('/usr/bin/pip.save'):
shutil.copy2('/usr/bin/pip.save', '/usr/bin/pip')
os.remove('/usr/bin/pip.save')
# setup wrappers to ensure envs are used for scripts
install_or_update_charm_env()
for wrapper in ('charms.reactive', 'charms.reactive.sh',
'chlp', 'layer_option'):
src = os.path.join('/usr/local/sbin', 'charm-env')
dst = os.path.join('/usr/local/sbin', wrapper)
if not os.path.exists(dst):
os.symlink(src, dst)
if cfg.get('use_venv'):
shutil.copy2('bin/layer_option', vbin)
else:
shutil.copy2('bin/layer_option', '/usr/local/bin/')
# re-link the charm copy to the wrapper in case charms
# call bin/layer_option directly (as was the old pattern)
os.remove('bin/layer_option')
os.symlink('/usr/local/sbin/layer_option', 'bin/layer_option')
# flag us as having already bootstrapped so we don't do it again
open('wheelhouse/.bootstrapped', 'w').close()
if is_upgrade:
# flag us as having already upgraded so we don't do it again
open('wheelhouse/.upgraded', 'w').close()
# Ensure that the newly bootstrapped libs are available.
# Note: this only seems to be an issue with namespace packages.
# Non-namespace-package libs (e.g., charmhelpers) are available
# without having to reload the interpreter. :/
reload_interpreter(vpy if cfg.get('use_venv') else sys.argv[0])
def _load_installed_versions(pip):
pip_freeze = check_output([pip, 'freeze']).decode('utf8')
versions = {}
for pkg_ver in pip_freeze.splitlines():
try:
req = Requirement.parse(pkg_ver)
except ValueError:
continue
versions.update({
req.project_name: LooseVersion(ver)
for op, ver in req.specs if op == '=='
})
return versions
def _load_wheelhouse_versions():
versions = {}
for wheel in glob('wheelhouse/*'):
pkg, ver = os.path.basename(wheel).rsplit('-', 1)
# nb: LooseVersion ignores the file extension
versions[pkg.replace('_', '-')] = LooseVersion(ver)
return versions
def _add_back_versions(pkgs, versions):
"""Add back the version strings to each of the packages.
The versions are LooseVersion() from _load_wheelhouse_versions(). This
function strips the ".zip" or ".tar.gz" from the end of the version string
and adds it back to the package in the form of <package_name>==<version>
If a package name is not a key in the versions dictionary, then it is
returned in the list unchanged.
:param pkgs: A list of package names
:type pkgs: List[str]
:param versions: A map of package to LooseVersion
:type versions: Dict[str, LooseVersion]
:returns: A list of (maybe) versioned packages
:rtype: List[str]
"""
def _strip_ext(s):
"""Strip an extension (if it exists) from the string
:param s: the string to strip an extension off if it exists
:type s: str
:returns: string without an extension of .zip or .tar.gz
:rtype: str
"""
for ending in [".zip", ".tar.gz"]:
if s.endswith(ending):
return s[:-len(ending)]
return s
def _maybe_add_version(pkg):
"""Maybe add back the version number to a package if it exists.
Adds the version number, if the package exists in the lexically
captured `versions` dictionary, in the form <pkg>==<version>. Strips
the extension if it exists.
:param pkg: the package name to (maybe) add the version number to.
:type pkg: str
"""
try:
return "{}=={}".format(pkg, _strip_ext(str(versions[pkg])))
except KeyError:
pass
return pkg
return [_maybe_add_version(pkg) for pkg in pkgs]
def _update_if_newer(pip, pkgs):
installed = _load_installed_versions(pip)
wheelhouse = _load_wheelhouse_versions()
for pkg in pkgs:
if pkg not in installed or wheelhouse[pkg] > installed[pkg]:
check_call([pip, 'install', '-U', '--no-index', '-f', 'wheelhouse',
pkg], env=_get_subprocess_env())
def install_or_update_charm_env():
# On Trusty python3-pkg-resources is not installed
try:
from pkg_resources import parse_version
except ImportError:
apt_install(['python3-pkg-resources'])
from pkg_resources import parse_version
try:
installed_version = parse_version(
check_output(['/usr/local/sbin/charm-env',
'--version']).decode('utf8'))
except (CalledProcessError, FileNotFoundError):
installed_version = parse_version('0.0.0')
try:
bundled_version = parse_version(
check_output(['bin/charm-env',
'--version']).decode('utf8'))
except (CalledProcessError, FileNotFoundError):
bundled_version = parse_version('0.0.0')
if installed_version < bundled_version:
shutil.copy2('bin/charm-env', '/usr/local/sbin/')
def activate_venv():
"""
Activate the venv if enabled in ``layer.yaml``.
This is handled automatically for normal hooks, but actions might
need to invoke this manually, using something like:
# Load modules from $JUJU_CHARM_DIR/lib
import sys
sys.path.append('lib')
from charms.layer.basic import activate_venv
activate_venv()
This will ensure that modules installed in the charm's
virtual environment are available to the action.
"""
from charms.layer import options
venv = os.path.abspath('../.venv')
vbin = os.path.join(venv, 'bin')
vpy = os.path.join(vbin, 'python')
use_venv = options.get('basic', 'use_venv')
if use_venv and '.venv' not in sys.executable:
# activate the venv
os.environ['PATH'] = ':'.join([vbin, os.environ['PATH']])
reload_interpreter(vpy)
layer.patch_options_interface()
layer.import_layer_libs()
def reload_interpreter(python):
"""
Reload the python interpreter to ensure that all deps are available.
Newly installed modules in namespace packages sometimes seemt to
not be picked up by Python 3.
"""
os.execve(python, [python] + list(sys.argv), os.environ)
def apt_install(packages):
"""
Install apt packages.
This ensures a consistent set of options that are often missed but
should really be set.
"""
if isinstance(packages, (str, bytes)):
packages = [packages]
env = _get_subprocess_env()
if 'DEBIAN_FRONTEND' not in env:
env['DEBIAN_FRONTEND'] = 'noninteractive'
cmd = ['apt-get',
'--option=Dpkg::Options::=--force-confold',
'--assume-yes',
'install']
for attempt in range(3):
try:
check_call(cmd + packages, env=env)
except CalledProcessError:
if attempt == 2: # third attempt
raise
try:
# sometimes apt-get update needs to be run
check_call(['apt-get', 'update'], env=env)
except CalledProcessError:
# sometimes it's a dpkg lock issue
pass
sleep(5)
else:
break
def yum_install(packages):
""" Installs packages with yum.
This function largely mimics the apt_install function for consistency.
"""
if packages:
env = os.environ.copy()
cmd = ['yum', '-y', 'install']
for attempt in range(3):
try:
check_call(cmd + packages, env=env)
except CalledProcessError:
if attempt == 2:
raise
try:
check_call(['yum', 'update'], env=env)
except CalledProcessError:
pass
sleep(5)
else:
break
else:
pass
def init_config_states():
import yaml
from charmhelpers.core import hookenv
from charms.reactive import set_state
from charms.reactive import toggle_state
config = hookenv.config()
config_defaults = {}
config_defs = {}
config_yaml = os.path.join(hookenv.charm_dir(), 'config.yaml')
if os.path.exists(config_yaml):
with open(config_yaml) as fp:
config_defs = yaml.safe_load(fp).get('options', {})
config_defaults = {key: value.get('default')
for key, value in config_defs.items()}
for opt in config_defs.keys():
if config.changed(opt):
set_state('config.changed')
set_state('config.changed.{}'.format(opt))
toggle_state('config.set.{}'.format(opt), config.get(opt))
toggle_state('config.default.{}'.format(opt),
config.get(opt) == config_defaults[opt])
def clear_config_states():
from charmhelpers.core import hookenv, unitdata
from charms.reactive import remove_state
config = hookenv.config()
remove_state('config.changed')
for opt in config.keys():
remove_state('config.changed.{}'.format(opt))
remove_state('config.set.{}'.format(opt))
remove_state('config.default.{}'.format(opt))
unitdata.kv().flush()