0d8c4270c0
To avoid any confusion, commands passed to exec_sudo() should be a list of "str"s. Log a message if we see unicode issues. This also adds a debug trace of all output. stderr is captured. This is modified to raise CalledProcessError on failure, like check_call(). Calls that are ok to fail will need to explicitly catch and ignore this. The two calls that we expect to fail are wrapped We wish to try rolling back if one of these command raises an exception. Modify the create handler to initiate rollback on all exceptions. Change-Id: Iee4fa41ffaf243e4728bf3a5eeec5c8fa8d2dadc
334 lines
12 KiB
Python
334 lines
12 KiB
Python
# Copyright 2016-2017 Andreas Florath (andreas@florath.net)
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
# not use this file except in compliance with the License. You may obtain
|
|
# a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
# License for the specific language governing permissions and limitations
|
|
# under the License.
|
|
|
|
import codecs
|
|
from diskimage_builder.block_device.blockdevicesetupexception \
|
|
import BlockDeviceSetupException
|
|
from diskimage_builder.graph.digraph import Digraph
|
|
import json
|
|
import logging
|
|
import os
|
|
import shutil
|
|
from stevedore import extension
|
|
import sys
|
|
import yaml
|
|
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
|
|
class BlockDevice(object):
|
|
"""Handles block devices.
|
|
|
|
This class handles the complete setup and deletion of all aspects
|
|
of the block device level.
|
|
|
|
A typical call sequence:
|
|
|
|
cmd_init: initialized the block device level config. After this
|
|
call it is possible to e.g. query information from the (partially
|
|
automatic generated) internal state like root-label.
|
|
|
|
cmd_getval: retrieve information about the (internal) block device
|
|
state like the block image device (for bootloader) or the
|
|
root-label (for writing fstab).
|
|
|
|
cmd_create: creates all the different aspects of the block
|
|
device. When this call is successful, the complete block level
|
|
device is set up, filesystems are created and are mounted at
|
|
the correct position.
|
|
After this call it is possible to copy / install all the needed
|
|
files into the appropriate directories.
|
|
|
|
cmd_umount: unmount and detaches all directories and used many
|
|
resources. After this call the used (e.g.) images are still
|
|
available for further handling, e.g. converting from raw in
|
|
some other format.
|
|
|
|
cmd_cleanup: removes everything that was created with the
|
|
'cmd_create' call, i.e. all images files themselves and
|
|
internal temporary configuration.
|
|
|
|
cmd_delete: unmounts and removes everything that was created
|
|
during the 'cmd_create' all. This call should be used in error
|
|
conditions when there is the need to remove all allocated
|
|
resources immediately and as good as possible.
|
|
From the functional point of view this is mostly the same as a
|
|
call to 'cmd_umount' and 'cmd_cleanup' - but is typically more
|
|
error tolerance.
|
|
|
|
In a script this should be called in the following way:
|
|
|
|
dib-block-device --phase=init ...
|
|
# From that point the database can be queried, like
|
|
ROOT_LABEL=$(dib-block-device --phase=getval --symbol=root-label ...)
|
|
|
|
Please note that currently the dib-block-device executable can
|
|
only be used outside the chroot.
|
|
|
|
dib-block-device --phase=create ...
|
|
trap "dib-block-device --phase=delete ..." EXIT
|
|
# copy / install files
|
|
dib-block-device --phase=umount ...
|
|
# convert image(s)
|
|
dib-block-device --phase=cleanup ...
|
|
trap - EXIT
|
|
"""
|
|
|
|
def _merge_into_config(self):
|
|
"""Merge old (default) config into new
|
|
|
|
There is the need to be compatible using some old environment
|
|
variables. This is done in the way, that if there is no
|
|
explicit value given, these values are inserted into the current
|
|
configuration.
|
|
"""
|
|
for entry in self.config:
|
|
for k, v in entry.items():
|
|
if k == 'mkfs':
|
|
if 'name' not in v:
|
|
continue
|
|
if v['name'] != 'mkfs_root':
|
|
continue
|
|
if 'type' not in v \
|
|
and 'root-fs-type' in self.params:
|
|
v['type'] = self.params['root-fs-type']
|
|
if 'opts' not in v \
|
|
and 'root-fs-opts' in self.params:
|
|
v['opts'] = self.params['root-fs-opts']
|
|
if 'label' not in v \
|
|
and 'root-label' in self.params:
|
|
if self.params['root-label'] is not None:
|
|
v['label'] = self.params['root-label']
|
|
else:
|
|
v['label'] = "cloudimg-rootfs"
|
|
|
|
@staticmethod
|
|
def _config_tree_to_digraph(tconfig, plugin_manager):
|
|
"""Converts a possible tree-like config into a complete digraph"""
|
|
dconfig = []
|
|
for config_entry in tconfig:
|
|
if len(config_entry) != 1:
|
|
logger.error("Invalid config entry: more than one key "
|
|
"on top level [%s]" % config_entry)
|
|
raise BlockDeviceSetupException(
|
|
"Top level config must contain exactly one key per entry")
|
|
logger.debug("Config entry [%s]" % config_entry)
|
|
config_key = list(config_entry)[0]
|
|
config_value = config_entry[config_key]
|
|
name = config_value['name'] \
|
|
if 'name' in config_value else None
|
|
if config_key not in plugin_manager:
|
|
dconfig.append(config_entry)
|
|
else:
|
|
plugin_manager[config_key].plugin \
|
|
.tree_config.config_tree_to_digraph(
|
|
config_key, config_value, dconfig, name,
|
|
plugin_manager)
|
|
return dconfig
|
|
|
|
@staticmethod
|
|
def _load_json(file_name):
|
|
if os.path.exists(file_name):
|
|
with codecs.open(file_name, encoding="utf-8", mode="r") as fd:
|
|
return json.load(fd)
|
|
return None
|
|
|
|
def __init__(self, args):
|
|
logger.debug("Creating BlockDevice object")
|
|
logger.debug("Param file [%s]" % args.params)
|
|
self.args = args
|
|
|
|
with open(self.args.params) as param_fd:
|
|
self.params = yaml.safe_load(param_fd)
|
|
logger.debug("Params [%s]" % self.params)
|
|
|
|
self.state_dir = os.path.join(
|
|
self.params['build-dir'], "states/block-device")
|
|
self.state_json_file_name \
|
|
= os.path.join(self.state_dir, "state.json")
|
|
self.plugin_manager = extension.ExtensionManager(
|
|
namespace='diskimage_builder.block_device.plugin',
|
|
invoke_on_load=False)
|
|
self.config_json_file_name \
|
|
= os.path.join(self.state_dir, "config.json")
|
|
|
|
self.config = self._load_json(self.config_json_file_name)
|
|
self.state = self._load_json(self.state_json_file_name)
|
|
logger.debug("Using state [%s]", self.state)
|
|
|
|
# This needs to exists for the state and config files
|
|
try:
|
|
os.makedirs(self.state_dir)
|
|
except OSError:
|
|
pass
|
|
|
|
def write_state(self, state):
|
|
logger.debug("Write state [%s]" % self.state_json_file_name)
|
|
with open(self.state_json_file_name, "w") as fd:
|
|
json.dump(state, fd)
|
|
|
|
def create_graph(self, config, default_config):
|
|
logger.debug("Create graph [%s]" % config)
|
|
# This is the directed graph of nodes: each parse method must
|
|
# add the appropriate nodes and edges.
|
|
dg = Digraph()
|
|
|
|
for config_entry in config:
|
|
if len(config_entry) != 1:
|
|
logger.error("Invalid config entry: more than one key "
|
|
"on top level [%s]" % config_entry)
|
|
raise BlockDeviceSetupException(
|
|
"Top level config must contain exactly one key per entry")
|
|
logger.debug("Config entry [%s]" % config_entry)
|
|
cfg_obj_name = list(config_entry.keys())[0]
|
|
cfg_obj_val = config_entry[cfg_obj_name]
|
|
|
|
# As the first step the configured objects are created
|
|
# (if it exists)
|
|
if cfg_obj_name not in self.plugin_manager:
|
|
logger.error("Configured top level element [%s] "
|
|
"does not exists." % cfg_obj_name)
|
|
return 1
|
|
cfg_obj = self.plugin_manager[cfg_obj_name].plugin(
|
|
cfg_obj_val, default_config)
|
|
# At this point it is only possible to add the nodes:
|
|
# adding the edges needs all nodes first.
|
|
cfg_obj.insert_nodes(dg)
|
|
|
|
# Now that all the nodes exists: add also the edges
|
|
for node in dg.get_iter_nodes_values():
|
|
node.insert_edges(dg)
|
|
|
|
call_order = dg.topological_sort()
|
|
logger.debug("Call order [%s]" % (list(call_order)))
|
|
return dg, call_order
|
|
|
|
def create(self, result, rollback):
|
|
dg, call_order = self.create_graph(self.config, self.params)
|
|
for node in call_order:
|
|
node.create(result, rollback)
|
|
|
|
def cmd_init(self):
|
|
"""Initialize block device setup
|
|
|
|
This initializes the block device setup layer. One major task
|
|
is to parse and check the configuration, write it down for
|
|
later examiniation and execution.
|
|
"""
|
|
with open(self.params['config'], "rt") as config_fd:
|
|
self.config = yaml.safe_load(config_fd)
|
|
logger.debug("Config before merge [%s]" % self.config)
|
|
self.config = self._config_tree_to_digraph(self.config,
|
|
self.plugin_manager)
|
|
logger.debug("Config before merge [%s]" % self.config)
|
|
self._merge_into_config()
|
|
logger.debug("Final config [%s]" % self.config)
|
|
# Write the final config
|
|
with open(self.config_json_file_name, "wt") as fd:
|
|
json.dump(self.config, fd)
|
|
logger.info("Wrote final block device config to [%s]"
|
|
% self.config_json_file_name)
|
|
|
|
def cmd_getval(self):
|
|
"""Retrieve value from block device level
|
|
|
|
This is needed for backward compatibility (non python) access
|
|
to (internal) configuration.
|
|
"""
|
|
symbol = self.args.symbol
|
|
logger.info("Getting value for [%s]" % symbol)
|
|
if symbol == 'image-block-partition':
|
|
# If there is no partition needed, pass back directly the
|
|
# image.
|
|
if 'root' in self.state['blockdev']:
|
|
print("%s" % self.state['blockdev']['root']['device'])
|
|
else:
|
|
print("%s" % self.state['blockdev']['image0']['device'])
|
|
return 0
|
|
if symbol == 'image-path':
|
|
print("%s" % self.state['blockdev']['image0']['image'])
|
|
return 0
|
|
logger.error("Invalid symbol [%s] for getval" % symbol)
|
|
return 1
|
|
|
|
def cmd_create(self):
|
|
"""Creates the block device"""
|
|
|
|
logger.info("create() called")
|
|
logger.debug("Using config [%s]" % self.config)
|
|
|
|
self.state = {}
|
|
rollback = []
|
|
|
|
try:
|
|
self.create(self.state, rollback)
|
|
except Exception:
|
|
logger.exception("Create failed; rollback initiated")
|
|
for rollback_cb in reversed(rollback):
|
|
rollback_cb()
|
|
sys.exit(1)
|
|
|
|
self.write_state(self.state)
|
|
|
|
logger.info("create() finished")
|
|
return 0
|
|
|
|
def cmd_umount(self):
|
|
"""Unmounts the blockdevice and cleanup resources"""
|
|
if self.state is None:
|
|
logger.info("State already cleaned - no way to do anything here")
|
|
return 0
|
|
|
|
# Deleting must be done in reverse order
|
|
dg, call_order = self.create_graph(self.config, self.params)
|
|
reverse_order = reversed(call_order)
|
|
|
|
if dg is None:
|
|
return 0
|
|
for node in reverse_order:
|
|
node.umount(self.state)
|
|
|
|
return 0
|
|
|
|
def cmd_cleanup(self):
|
|
"""Cleanup all remaining relicts - in good case"""
|
|
|
|
# Deleting must be done in reverse order
|
|
dg, call_order = self.create_graph(self.config, self.params)
|
|
reverse_order = reversed(call_order)
|
|
|
|
for node in reverse_order:
|
|
node.cleanup(self.state)
|
|
|
|
logger.info("Removing temporary dir [%s]" % self.state_dir)
|
|
shutil.rmtree(self.state_dir)
|
|
|
|
return 0
|
|
|
|
def cmd_delete(self):
|
|
"""Cleanup all remaining relicts - in case of an error"""
|
|
|
|
# Deleting must be done in reverse order
|
|
dg, call_order = self.create_graph(self.config, self.params)
|
|
reverse_order = reversed(call_order)
|
|
|
|
for node in reverse_order:
|
|
node.delete(self.state)
|
|
|
|
logger.info("Removing temporary dir [%s]" % self.state_dir)
|
|
shutil.rmtree(self.state_dir)
|
|
|
|
return 0
|