def printlayerinfo(args, layers, outfile=stdout):
if args.quiet:
for l in layers:
print(l[':short_id'], file=outfile)
return
total_size = 0
fields_fmt = '\t'.join(['{:<23}'] + ['{:<15}'] * 5)
print(fields_fmt.format('REPO TAG', 'IMAGE ID', 'PARENT ID', 'CREATED',
'LAYER SIZE', 'VIRTUAL SIZE'),
file=outfile)
total_size = sum((l['Size'] for l in layers))
for layer in layers:
try:
image_tag = layer[':repo_tags'][0]
except IndexError:
image_tag = '-'
image_id = layer[':short_id']
parent_id = layer[':parent_id'][:12].lower()
if not parent_id:
parent_id = '-'
created = naturaltime(layer[':created_dt'])
layer_size = naturalsize(layer['Size'])
virt_size = naturalsize(total_size)
print(fields_fmt.format(image_tag, image_id, parent_id, created,
layer_size, virt_size),
file=outfile)
total_size -= layer['Size']
def printlayerinfo(args, layers, outfile=stdout):
if args.quiet:
for l in layers:
print(l[':short_id'], file=outfile)
return
total_size = 0
fields_fmt = '\t'.join([ '{:<23}' ] + [ '{:<15}' ] * 5)
print(fields_fmt.format('REPO TAG', 'IMAGE ID', 'PARENT ID', 'CREATED', 'LAYER SIZE', 'VIRTUAL SIZE'), file=outfile)
total_size = sum(( l['Size'] for l in layers ))
for layer in layers:
try:
image_tag = layer[':repo_tags'][0]
except IndexError:
image_tag = '-'
image_id = layer[':short_id']
parent_id = layer[':parent_id'][:12].lower()
if not parent_id:
parent_id = '-'
created = naturaltime(layer[':created_dt'])
layer_size = naturalsize(layer['Size'])
virt_size = naturalsize(total_size)
print(fields_fmt.format(image_tag, image_id, parent_id, created, layer_size, virt_size), file=outfile)
total_size -= layer['Size']
def extractlayers(dc, layers, tar_file, top_most_layer=0):
"""
:param dc: a |docker.Client|_
:param layers: a sequence of inspection objects (likely retrieved with
:func:`inspectlayers`) corresponding to the layers to extract and
flatten in order of precedence
:param tar_file: a :class:`~tarfile.TarFile` open for writing to which
to write the flattened layer archive
:param top_most_layer: an image ID or an index into :obj:`layers`
indicating the most recent layer to retrieve (the default of ``0``
references the first item in :obj:`layers`; see below)
:raises docker.errors.APIError: on failure interacting with Docker
(e.g., failed connection, Docker not running, etc.)
:raises docker.errors.DockerException: on failure interacting with
Docker (e.g., bad image ID, etc.)
:raises UnsafeTarPath: - probably indicative of a bug in Docker
Retrieves the layers corresponding to the :obj:`layers` parameter and
extracts them into :obj:`tar_file`. Changes from layers corresponding
to smaller indexes in :obj:`layers` will overwrite or block those from
larger ones.
Callers will need to set the :obj:`top_most_layer` parameter if
:obj:`layers` is not in descending order. It is always safe to provide
the same value as the :obj:`image_spec` parameter to
:func:`inspectlayers`, but this may be ineffecient if that layer does
not appear in :obj:`layers`.
"""
if not layers:
_LOGGER.warning('nothing to extract')
return
image_spec = top_most_layer if not isinstance(top_most_layer, int) else layers[top_most_layer][':id']
tmp_dir = path_realpath(mkdtemp())
try:
image = logexception(_LOGGER, ERROR, 'unable to retrieve image layers from "{}": {{e}}'.format(image_spec), dc.get_image, image_spec)
with tarfile_open(mode='r|*', fileobj=image) as image_tar_file:
next_info = image_tar_file.next()
while next_info:
next_path = path_realpath(path_join(tmp_dir, next_info.name))
if not next_path.startswith(tmp_dir):
exc = UnsafeTarPath('unsafe path: "{}"'.format(next_info.name))
logexception(_LOGGER, ERROR, 'unable to retrieve entry from export of "{}": {{e}}'.format(image_spec), exc)
image_tar_file.extract(next_info, tmp_dir)
next_info = image_tar_file.next()
seen = set()
hides_subtrees = set()
# Look through each layer's archive (newest to oldest)
for layer in layers:
layer_id = layer[':id']
layer_tar_path = path_join(tmp_dir, layer_id, 'layer.tar')
with tarfile_open(layer_tar_path) as layer_tar_file:
next_info = layer_tar_file.next()
while next_info:
next_dirname = posixpath_dirname(next_info.name)
next_basename = posixpath_basename(next_info.name)
if next_basename.startswith(_WHITEOUT_PFX):
removed_path = posixpath_join(next_dirname, next_basename[_WHITEOUT_PFX_LEN:])
hides_subtrees.add(( removed_path, 'removal' ))
if removed_path in seen:
_LOGGER.debug('skipping removal "%s"', removed_path)
else:
_LOGGER.debug('hiding "%s" as removed', removed_path)
elif next_info.name in seen:
_LOGGER.debug('skipping "%s" as overwritten', next_info.name)
else:
next_name_len = len(next_info.name)
hidden = None
for h, deverbal in hides_subtrees: # https://en.wikipedia.org/wiki/deverbal
if len(h) > next_name_len:
continue
common_pfx = posixpath_commonprefix(( h, next_info.name ))
common_pfx_len = len(common_pfx)
if next_name_len == common_pfx_len \
or next_info.name[common_pfx_len:].startswith(posixpath_sep):
hidden = deverbal, h
break
if hidden:
_LOGGER.debug('skipping "%s" hidden by %s of %s', next_info.name, *hidden)
else:
mtime = naturaltime(datetime.utcfromtimestamp(next_info.mtime).replace(tzinfo=TZ_UTC))
_LOGGER.info('writing "%s" from "%s" to archive (size: %s; mode: %o; mtime: %s)', next_info.name, layer_id, naturalsize(next_info.size), next_info.mode, mtime)
if next_info.linkname:
# TarFile.extractfile() tries to do
# something weird when its parameter
# represents a link (see the docs)
fileobj = None
else:
fileobj = layer_tar_file.extractfile(next_info)
tar_file.addfile(next_info, fileobj)
seen.add(next_info.name)
if not next_info.isdir():
hides_subtrees.add(( next_info.name, 'presence' ))
next_info = layer_tar_file.next()
finally:
rmtree(tmp_dir, ignore_errors=True)
def extractlayers(dc, layers, tar_file, top_most_layer=0):
"""
:param dc: a |docker.Client|_
:param layers: a sequence of inspection objects (likely retrieved with
:func:`inspectlayers`) corresponding to the layers to extract and
flatten in order of precedence
:param tar_file: a :class:`~tarfile.TarFile` open for writing to which
to write the flattened layer archive
:param top_most_layer: an image ID or an index into :obj:`layers`
indicating the most recent layer to retrieve (the default of ``0``
references the first item in :obj:`layers`; see below)
:raises docker.errors.APIError: on failure interacting with Docker
(e.g., failed connection, Docker not running, etc.)
:raises docker.errors.DockerException: on failure interacting with
Docker (e.g., bad image ID, etc.)
:raises UnsafeTarPath: - probably indicative of a bug in Docker
Retrieves the layers corresponding to the :obj:`layers` parameter and
extracts them into :obj:`tar_file`. Changes from layers corresponding
to smaller indexes in :obj:`layers` will overwrite or block those from
larger ones.
Callers will need to set the :obj:`top_most_layer` parameter if
:obj:`layers` is not in descending order. It is always safe to provide
the same value as the :obj:`image_spec` parameter to
:func:`inspectlayers`, but this may be ineffecient if that layer does
not appear in :obj:`layers`.
"""
if not layers:
_LOGGER.warning('nothing to extract')
return
image_spec = top_most_layer if not isinstance(
top_most_layer, int) else layers[top_most_layer][':id']
tmp_dir = path_realpath(mkdtemp())
try:
image = logexception(
_LOGGER, ERROR,
'unable to retrieve image layers from "{}": {{e}}'.format(
image_spec), dc.get_image, image_spec)
with tarfile_open(mode='r|*', fileobj=image) as image_tar_file:
next_info = image_tar_file.next()
while next_info:
next_path = path_realpath(path_join(tmp_dir, next_info.name))
if not next_path.startswith(tmp_dir):
exc = UnsafeTarPath('unsafe path: "{}"'.format(
next_info.name))
logexception(
_LOGGER, ERROR,
'unable to retrieve entry from export of "{}": {{e}}'.
format(image_spec), exc)
image_tar_file.extract(next_info, tmp_dir)
next_info = image_tar_file.next()
seen = set()
hides_subtrees = set()
# Look through each layer's archive (newest to oldest)
for layer in layers:
layer_id = layer[':id']
layer_tar_path = path_join(tmp_dir, layer_id, 'layer.tar')
with tarfile_open(layer_tar_path) as layer_tar_file:
next_info = layer_tar_file.next()
while next_info:
next_dirname = posixpath_dirname(next_info.name)
next_basename = posixpath_basename(next_info.name)
if next_basename.startswith(_WHITEOUT_PFX):
removed_path = posixpath_join(
next_dirname, next_basename[_WHITEOUT_PFX_LEN:])
hides_subtrees.add((removed_path, 'removal'))
if removed_path in seen:
_LOGGER.debug('skipping removal "%s"',
removed_path)
else:
_LOGGER.debug('hiding "%s" as removed',
removed_path)
elif next_info.name in seen:
_LOGGER.debug('skipping "%s" as overwritten',
next_info.name)
else:
next_name_len = len(next_info.name)
hidden = None
for h, deverbal in hides_subtrees: # https://en.wikipedia.org/wiki/deverbal
if len(h) > next_name_len:
continue
common_pfx = posixpath_commonprefix(
(h, next_info.name))
common_pfx_len = len(common_pfx)
if next_name_len == common_pfx_len \
or next_info.name[common_pfx_len:].startswith(posixpath_sep):
hidden = deverbal, h
break
if hidden:
_LOGGER.debug('skipping "%s" hidden by %s of %s',
next_info.name, *hidden)
else:
mtime = naturaltime(
datetime.utcfromtimestamp(
next_info.mtime).replace(tzinfo=TZ_UTC))
_LOGGER.info(
'writing "%s" from "%s" to archive (size: %s; mode: %o; mtime: %s)',
next_info.name, layer_id,
naturalsize(next_info.size), next_info.mode,
mtime)
if next_info.linkname:
# TarFile.extractfile() tries to do
# something weird when its parameter
# represents a link (see the docs)
fileobj = None
else:
fileobj = layer_tar_file.extractfile(next_info)
tar_file.addfile(next_info, fileobj)
seen.add(next_info.name)
if not next_info.isdir():
hides_subtrees.add(
(next_info.name, 'presence'))
next_info = layer_tar_file.next()
finally:
rmtree(tmp_dir, ignore_errors=True)
