diff options
Diffstat (limited to 'src/buildstream/plugins/sources/bzr.py')
| -rw-r--r-- | src/buildstream/plugins/sources/bzr.py | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/src/buildstream/plugins/sources/bzr.py b/src/buildstream/plugins/sources/bzr.py new file mode 100644 index 000000000..e59986da6 --- /dev/null +++ b/src/buildstream/plugins/sources/bzr.py @@ -0,0 +1,210 @@ +# Copyright (C) 2017 Codethink Limited +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2 of the License, or (at your option) any later version. +# +# This library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with this library. If not, see <http://www.gnu.org/licenses/>. +# +# Authors: +# Jonathan Maw <jonathan.maw@codethink.co.uk> + +""" +bzr - stage files from a bazaar repository +========================================== + +**Host dependencies:** + + * bzr + +**Usage:** + +.. code:: yaml + + # Specify the bzr source kind + kind: bzr + + # Specify the bzr url. Bazaar URLs come in many forms, see + # `bzr help urlspec` for more information. Using an alias defined + # in your project configuration is encouraged. + url: https://launchpad.net/bzr + + # Specify the tracking branch. This is mandatory, as bzr cannot identify + # an individual revision outside its branch. bzr URLs that omit the branch + # name implicitly specify the trunk branch, but bst requires this to be + # explicit. + track: trunk + + # Specify the ref. This is a revision number. This is usually a decimal, + # but revisions on a branch are of the form + # <revision-branched-from>.<branch-number>.<revision-since-branching> + # e.g. 6622.1.6. + # The ref must be specified to build, and 'bst source track' will update the + # revision number to the one on the tip of the branch specified in 'track'. + ref: 6622 + +See :ref:`built-in functionality doumentation <core_source_builtins>` for +details on common configuration options for sources. +""" + +import os +import shutil +import fcntl +from contextlib import contextmanager + +from buildstream import Source, SourceError, Consistency +from buildstream import utils + + +class BzrSource(Source): + # pylint: disable=attribute-defined-outside-init + + def configure(self, node): + self.node_validate(node, ['url', 'track', 'ref', *Source.COMMON_CONFIG_KEYS]) + + self.original_url = self.node_get_member(node, str, 'url') + self.tracking = self.node_get_member(node, str, 'track') + self.ref = self.node_get_member(node, str, 'ref', None) + self.url = self.translate_url(self.original_url) + + def preflight(self): + # Check if bzr is installed, get the binary at the same time. + self.host_bzr = utils.get_host_tool('bzr') + + def get_unique_key(self): + return [self.original_url, self.tracking, self.ref] + + def get_consistency(self): + if self.ref is None or self.tracking is None: + return Consistency.INCONSISTENT + + # Lock for the _check_ref() + with self._locked(): + if self._check_ref(): + return Consistency.CACHED + else: + return Consistency.RESOLVED + + def load_ref(self, node): + self.ref = self.node_get_member(node, str, 'ref', None) + + def get_ref(self): + return self.ref + + def set_ref(self, ref, node): + node['ref'] = self.ref = ref + + def track(self): + with self.timed_activity("Tracking {}".format(self.url), + silent_nested=True), self._locked(): + self._ensure_mirror(skip_ref_check=True) + ret, out = self.check_output([self.host_bzr, "version-info", + "--custom", "--template={revno}", + self._get_branch_dir()], + fail="Failed to read the revision number at '{}'" + .format(self._get_branch_dir())) + if ret != 0: + raise SourceError("{}: Failed to get ref for tracking {}".format(self, self.tracking)) + + return out + + def fetch(self): + with self.timed_activity("Fetching {}".format(self.url), + silent_nested=True), self._locked(): + self._ensure_mirror() + + def stage(self, directory): + self.call([self.host_bzr, "checkout", "--lightweight", + "--revision=revno:{}".format(self.ref), + self._get_branch_dir(), directory], + fail="Failed to checkout revision {} from branch {} to {}" + .format(self.ref, self._get_branch_dir(), directory)) + # Remove .bzr dir + shutil.rmtree(os.path.join(directory, ".bzr")) + + def init_workspace(self, directory): + url = os.path.join(self.url, self.tracking) + with self.timed_activity('Setting up workspace "{}"'.format(directory), silent_nested=True): + # Checkout from the cache + self.call([self.host_bzr, "branch", + "--use-existing-dir", + "--revision=revno:{}".format(self.ref), + self._get_branch_dir(), directory], + fail="Failed to branch revision {} from branch {} to {}" + .format(self.ref, self._get_branch_dir(), directory)) + # Switch the parent branch to the source's origin + self.call([self.host_bzr, "switch", + "--directory={}".format(directory), url], + fail="Failed to switch workspace's parent branch to {}".format(url)) + + # _locked() + # + # This context manager ensures exclusive access to the + # bzr repository. + # + @contextmanager + def _locked(self): + lockdir = os.path.join(self.get_mirror_directory(), 'locks') + lockfile = os.path.join( + lockdir, + utils.url_directory_name(self.original_url) + '.lock' + ) + os.makedirs(lockdir, exist_ok=True) + with open(lockfile, 'w') as lock: + fcntl.flock(lock, fcntl.LOCK_EX) + try: + yield + finally: + fcntl.flock(lock, fcntl.LOCK_UN) + + def _check_ref(self): + # If the mirror doesnt exist yet, then we dont have the ref + if not os.path.exists(self._get_branch_dir()): + return False + + return self.call([self.host_bzr, "revno", + "--revision=revno:{}".format(self.ref), + self._get_branch_dir()]) == 0 + + def _get_branch_dir(self): + return os.path.join(self._get_mirror_dir(), self.tracking) + + def _get_mirror_dir(self): + return os.path.join(self.get_mirror_directory(), + utils.url_directory_name(self.original_url)) + + def _ensure_mirror(self, skip_ref_check=False): + mirror_dir = self._get_mirror_dir() + bzr_metadata_dir = os.path.join(mirror_dir, ".bzr") + if not os.path.exists(bzr_metadata_dir): + self.call([self.host_bzr, "init-repo", "--no-trees", mirror_dir], + fail="Failed to initialize bzr repository") + + branch_dir = os.path.join(mirror_dir, self.tracking) + branch_url = self.url + "/" + self.tracking + if not os.path.exists(branch_dir): + # `bzr branch` the branch if it doesn't exist + # to get the upstream code + self.call([self.host_bzr, "branch", branch_url, branch_dir], + fail="Failed to branch from {} to {}".format(branch_url, branch_dir)) + + else: + # `bzr pull` the branch if it does exist + # to get any changes to the upstream code + self.call([self.host_bzr, "pull", "--directory={}".format(branch_dir), branch_url], + fail="Failed to pull new changes for {}".format(branch_dir)) + + if not skip_ref_check and not self._check_ref(): + raise SourceError("Failed to ensure ref '{}' was mirrored".format(self.ref), + reason="ref-not-mirrored") + + +def setup(): + return BzrSource |