Spotter-VM/lxc-build
2018-09-05 19:29:56 +02:00

127 lines
3.6 KiB
Python
Executable File

#!/usr/bin/python3
import os
import shutil
import subprocess
import sys
LXC_ROOT = '/var/lib/lxc'
CONFIG_TEMPLATE = '''# Image name
lxc.uts.name = {image}
# Network
lxc.net.0.type = veth
lxc.net.0.link = lxcbr0
lxc.net.0.flags = up
lxc.net.0.ipv4.address = 172.17.0.254/16
lxc.net.0.ipv4.gateway = auto
# Volumes
lxc.rootfs.path = {rootfs}
# Mounts
lxc.mount.entry = /etc/hosts etc/hosts none bind 0 0
lxc.mount.entry = /etc/resolv.conf etc/resolv.conf none bind 0 0
{mounts}
# Init
lxc.init.cmd = {cmd}
lxc.init.uid = {uid}
lxc.init.gid = {gid}
# Halt
lxc.signal.halt = SIGTERM
# Other
lxc.arch = x86_64
lxc.cap.drop = sys_admin
lxc.include = /usr/share/lxc/config/alpine.common.conf
'''
image = None
layers = []
mounts = []
uid = 0
gid = 0
cmd = '/bin/true'
script = []
in_script = False
if os.path.isfile(sys.argv[1]):
lxcfile = os.path.realpath(sys.argv[1])
build_context = os.path.dirname(lxcfile)
else:
build_context = os.path.realpath(sys.argv[1])
lxcfile = os.path.join(build_context, 'lxcfile')
def rebuild_config():
rootfs_layers = [os.path.join(LXC_ROOT, l) for l in layers]
for layer in rootfs_layers:
os.makedirs(layer, 0o755, True)
if len(rootfs_layers) == 1:
rootfs_path = rootfs_layers[0]
else:
rootfs_path = 'overlay:{}'.format(':'.join(rootfs_layers))
mount_entries = '\n'.join(['lxc.mount.entry = {} none bind 0 0'.format(m) for m in mounts])
with open(os.path.join(LXC_ROOT, image, 'config'), 'w') as fd:
fd.write(CONFIG_TEMPLATE.format(image=image, rootfs=rootfs_path, mounts=mount_entries, uid=uid, gid=gid, cmd=cmd))
def fix_world():
world_items = []
last_world = []
for layer in layers[:-1]:
with open(os.path.join(LXC_ROOT, layer, 'etc/apk/world'), 'r') as fd:
last_world = fd.read().splitlines()
world_items.extend(last_world)
world_items = sorted(set(world_items))
if world_items != sorted(last_world):
os.makedirs(os.path.join(LXC_ROOT, layers[-1], 'etc/apk'))
with open(os.path.join(LXC_ROOT, layers[-1], 'etc/apk/world'), 'w') as fd:
fd.writelines(world_items)
def run_script():
script_filename = os.path.join(LXC_ROOT, layers[-1], 'run.sh')
with open(script_filename, 'w') as fd:
fd.write(' && '.join([s for s in script]))
os.chmod(script_filename, 0o700)
subprocess.run(['lxc-execute', '-n', image, '--', '/bin/sh', '-lvc', '/run.sh'], check=True)
os.unlink(script_filename)
def copy_files(src, dst):
src = os.path.join(build_context, src)
dst = os.path.join(LXC_ROOT, layers[-1], dst)
shutil.copytree(src, dst)
with open(lxcfile, 'r') as fd:
recipe = fd.read().splitlines()
for line in recipe:
if line == 'RUN':
in_script = False
run_script()
elif in_script and line and not line.startswith('#'):
script.append(line)
elif line == 'SCRIPT':
script = []
in_script = True
elif line.startswith('IMAGE'):
image = line.split()[1]
os.makedirs(os.path.join(LXC_ROOT, image), 0o755, True)
elif line.startswith('LAYER'):
layers.append(line.split()[1])
rebuild_config()
elif line == 'FIXWORLD':
fix_world()
elif line.startswith('COPY'):
copy_files(*line.split()[1:2])
elif line.startswith('MOUNT'):
mounts.append(line.split()[1])
rebuild_config()
elif line.startswith('USER'):
uid = line.split()[1]
gid = line.split()[2]
rebuild_config()
elif line.startswith('CMD'):
cmd = line.split()[1]
rebuild_config()
layers.append('{}/delta0'.format(image))