Newer
Older
# Copyright (C) 2016 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information
import abc
import io
import os
import tarfile
import tempfile
from pathlib import Path
from swh.core import hashutil
SKIPPED_MESSAGE = (b'This content have not been retrieved in '
b'Software Heritage archive due to its size')
HIDDEN_MESSAGE = (b'This content is hidden')
def get_tar_bytes(path, arcname=None):
path = Path(path)
if not arcname:
arcname = path.name
tar_buffer = io.BytesIO()
tar = tarfile.open(fileobj=tar_buffer, mode='w')
tar.add(str(path), arcname=arcname)
return tar_buffer.getbuffer()
class BaseVaultCooker(metaclass=abc.ABCMeta):
"""Abstract base class for the vault's bundle creators
This class describes a common API for the cookers.
To define a new cooker, inherit from this class and override:
- CACHE_TYPE_KEY: key to use for the bundle to reference in cache
- def cook(obj_id): cook the object into a bundle
- def notify_bundle_ready(notif_data, bundle_id): notify the
bundle is ready.
def __init__(self, storage, cache):
self.storage = storage
self.cache = cache
@abc.abstractmethod
def cook(self, obj_id):
"""Cook the requested object into a bundle
The type of the object represented by the id depends on the
concrete class. Very likely, each type of bundle will have its
own cooker class.
Args:
obj_id: id of the object to be cooked into a bundle.
"""
def update_cache(self, id, bundle_content):
"""Update the cache with id and bundle_content.
"""
self.cache.add(self.CACHE_TYPE_KEY, id, bundle_content)
@abc.abstractmethod
def notify_bundle_ready(self, notif_data, bundle_id):
"""Notify the bundle bundle_id is ready.
"""
pass
class DirectoryVaultCooker(BaseVaultCooker):
"""Cooker to create a directory bundle """
def __init__(self, storage, cache):
"""Initialize a cooker that create directory bundles
Args:
storage: source storage where content are retrieved.
cache: destination storage where the cooked bundle are stored.
"""
self.storage = storage
self.cache = cache
def cook(self, obj_id):
"""Cook the requested directory into a Bundle
Args:
obj_id (bytes): the id of the directory to be cooked.
Returns:
bytes that correspond to the bundle
"""
# Create the bytes that corresponds to the compressed
# directory.
directory_cooker = DirectoryCooker(self.storage)
bundle_content = directory_cooker.get_directory_bytes(obj_id)
self.update_cache(obj_id, bundle_content)
# Make a notification that the bundle have been cooked
# NOT YET IMPLEMENTED see TODO in function.
notif_data='Bundle %s ready' % hashutil.hash_to_hex(obj_id),
bundle_id=obj_id)
def notify_bundle_ready(self, notif_data, bundle_id):
# TODO plug this method with the notification method once
# done.
pass
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
class RevisionVaultCooker(BaseVaultCooker):
"""Cooker to create a directory bundle """
CACHE_TYPE_KEY = 'revision'
def __init__(self, storage, cache):
"""Initialize a cooker that create revision bundles
Args:
storage: source storage where content are retrieved.
cache: destination storage where the cooked bundle are stored.
"""
self.storage = storage
self.cache = cache
def cook(self, obj_id):
"""Cook the requested revision into a Bundle
Args:
obj_id (bytes): the id of the revision to be cooked.
Returns:
bytes that correspond to the bundle
"""
directory_cooker = DirectoryCooker(self.storage)
with tempfile.TemporaryDirectory(suffix='.cook') as root_tmp:
root = Path(root_tmp)
for revision in self.storage.revision_log([obj_id]):
revdir = root / hashutil.hash_to_hex(revision['id'])
revdir.mkdir()
directory_cooker.build_directory(revision['directory'],
str(revdir).encode())
bundle_content = get_tar_bytes(root_tmp,
hashutil.hash_to_hex(obj_id))
# Cache the bundle
self.update_cache(obj_id, bundle_content)
# Make a notification that the bundle have been cooked
# NOT YET IMPLEMENTED see TODO in function.
self.notify_bundle_ready(
notif_data='Bundle %s ready' % hashutil.hash_to_hex(obj_id),
bundle_id=obj_id)
def notify_bundle_ready(self, notif_data, bundle_id):
# TODO plug this method with the notification method once
# done.
pass
class DirectoryCooker():
"""Creates a cooked directory from its sha1_git in the db.
Warning: This is NOT a directly accessible cooker, but a low-level
one that executes the manipulations.
"""
def __init__(self, storage):
self.storage = storage
def get_directory_bytes(self, dir_id):
# Create temporary folder to retrieve the files into.
root = bytes(tempfile.mkdtemp(prefix='directory.',
suffix='.cook'), 'utf8')
self.build_directory(dir_id, root)
# Use the created directory to make a bundle with the data as
# a compressed directory.
bundle_content = self._create_bundle_content(
root,
hashutil.hash_to_hex(dir_id))
return bundle_content
def build_directory(self, dir_id, root):
# Retrieve data from the database.
data = self.storage.directory_ls(dir_id, recursive=True)
# Split into files and directory data.
# TODO(seirl): also handle revision data.
data1, data2 = itertools.tee(data, 2)
dir_data = (entry['name'] for entry in data1 if entry['type'] == 'dir')
file_data = (entry for entry in data2 if entry['type'] == 'file')
# Recreate the directory's subtree and then the files into it.
self._create_tree(root, dir_data)
self._create_files(root, file_data)
def _create_tree(self, root, directory_paths):
"""Create a directory tree from the given paths
The tree is created from `root` and each given path in
`directory_paths` will be created.
"""
# Directories are sorted by depth so they are created in the
# right order
bsep = bytes(os.path.sep, 'utf8')
dir_names = sorted(
directory_paths,
key=lambda x: len(x.split(bsep)))
for dir_name in dir_names:
os.makedirs(os.path.join(root, dir_name))
def _create_files(self, root, file_datas):
"""Create the files according to their status.
"""
# Then create the files
for file_data in file_datas:
path = os.path.join(root, file_data['name'])
status = file_data['status']
perms = file_data['perms']
if status == 'absent':
self._create_file_absent(path)
elif status == 'hidden':
self._create_file_hidden(path)
else:
content = self._get_file_content(file_data['sha1'])
self._create_file(path, content, perms)
def _create_file(self, path, content, perms=0o100644):
"""Create the given file and fill it with content.
"""
if perms not in (0o100644, 0o100755, 0o120000):
logging.warning('File {} has invalid permission {}, '
'defaulting to 644.'.format(path, perms))
if perms == 0o120000: # Symbolic link
os.symlink(content, path)
else:
with open(path, 'wb') as f:
f.write(content)
os.chmod(path, perms & 0o777)
def _get_file_content(self, obj_id):
"""Get the content of the given file.
"""
content = list(self.storage.content_get([obj_id]))[0]['data']
return content
def _create_file_absent(self, path):
"""Create a file that indicates a skipped content
Create the given file but fill it with a specific content to
indicate that the content have not been retrieved by the
software heritage archive due to its size.
"""
self._create_file(self, SKIPPED_MESSAGE)
def _create_file_hidden(self, path):
"""Create a file that indicates an hidden content
Create the given file but fill it with a specific content to
indicate that the content could not be retrieved due to
privacy policy.
"""
self._create_file(self, HIDDEN_MESSAGE)
def _create_bundle_content(self, path, hex_dir_id):
"""Create a bundle from the given directory
Args:
path: location of the directory to package.
hex_dir_id: hex representation of the directory id
Returns:
bytes that represent the compressed directory as a bundle.
return get_tar_bytes(path.decode(), hex_dir_id)