From 3f9361dd2d9a952e71d30b8e71e8ad5dd220e1dd Mon Sep 17 00:00:00 2001 From: Richard Maw Date: Fri, 20 Sep 2013 14:15:14 +0000 Subject: b&m: Add system branch initializing context manager This creates an object that the with statement can use to handle the context and clean up the workspace if the body raises an exception. This is roughly equivalent to having a function that takes a callback of what to do while the branch is being initialized, but with less boilerplate at the call site. contextlib is used to create a context manager from a generator function. This is less verbose than defining a class with __enter__ and __exit__ methods. --- morphlib/plugins/branch_and_merge_new_plugin.py | 35 +++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/morphlib/plugins/branch_and_merge_new_plugin.py b/morphlib/plugins/branch_and_merge_new_plugin.py index 39552ef0..88ace701 100644 --- a/morphlib/plugins/branch_and_merge_new_plugin.py +++ b/morphlib/plugins/branch_and_merge_new_plugin.py @@ -15,6 +15,7 @@ import cliapp +import contextlib import glob import logging import os @@ -97,6 +98,40 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): ws = morphlib.workspace.open('.') self.app.output.write('%s\n' % ws.root) + # TODO: Move this somewhere nicer + @contextlib.contextmanager + def _initializing_system_branch(self, ws, root_url, system_branch, + cached_repo, base_ref): + '''A context manager for system branches under construction. + + The purpose of this context manager is to factor out the branch + cleanup code for if an exception occurs while a branch is being + constructed. + + This could be handled by a higher order function which takes + a function to initialize the branch as a parameter, but with + statements look nicer and are more obviously about resource + cleanup. + + ''' + root_dir = ws.get_default_system_branch_directory_name(system_branch) + try: + sb = morphlib.sysbranchdir.create( + root_dir, root_url, system_branch) + gd = sb.clone_cached_repo(cached_repo, base_ref) + + yield (sb, gd) + + gd.update_submodules(self.app) + gd.update_remotes() + + except BaseException as e: + # Oops. Clean up. + logging.error('Caught exception: %s' % str(e)) + logging.info('Removing half-finished branch %s' % system_branch) + self._remove_branch_dir_safe(ws.root, root_dir) + raise + def checkout(self, args): '''Check out an existing system branch. -- cgit v1.2.1 From 8bb01ef1b85794b8c865dc1fdb50c02acbbe3216 Mon Sep 17 00:00:00 2001 From: Richard Maw Date: Fri, 20 Sep 2013 14:19:44 +0000 Subject: b&m: checkout and branch use context manager --- morphlib/plugins/branch_and_merge_new_plugin.py | 43 ++++--------------------- 1 file changed, 7 insertions(+), 36 deletions(-) diff --git a/morphlib/plugins/branch_and_merge_new_plugin.py b/morphlib/plugins/branch_and_merge_new_plugin.py index 88ace701..7cd84898 100644 --- a/morphlib/plugins/branch_and_merge_new_plugin.py +++ b/morphlib/plugins/branch_and_merge_new_plugin.py @@ -159,6 +159,7 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): root_url = args[0] system_branch = args[1] + base_ref = system_branch self._require_git_user_config() @@ -174,27 +175,12 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): # Check the git branch exists. cached_repo.resolve_ref(system_branch) - root_dir = ws.get_default_system_branch_directory_name(system_branch) - - try: - # Create the system branch directory. This doesn't yet clone - # the root repository there. - sb = morphlib.sysbranchdir.create( - root_dir, root_url, system_branch) - - gd = sb.clone_cached_repo(cached_repo, system_branch) + with self._initializing_system_branch( + ws, root_url, system_branch, cached_repo, base_ref) as (sb, gd): if not self._checkout_has_systems(gd): - raise BranchRootHasNoSystemsError(root_url, system_branch) + raise BranchRootHasNoSystemsError(base_ref) - gd.update_submodules(self.app) - gd.update_remotes() - except BaseException as e: - # Oops. Clean up. - logging.error('Caught exception: %s' % str(e)) - logging.info('Removing half-finished branch %s' % system_branch) - self._remove_branch_dir_safe(ws.root, root_dir) - raise def branch(self, args): '''Create a new system branch. @@ -247,29 +233,14 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): # Make sure the base_ref exists. cached_repo.resolve_ref(base_ref) - root_dir = ws.get_default_system_branch_directory_name(system_branch) + with self._initializing_system_branch( + ws, root_url, system_branch, cached_repo, base_ref) as (sb, gd): - try: - # Create the system branch directory. This doesn't yet clone - # the root repository there. - sb = morphlib.sysbranchdir.create( - root_dir, root_url, system_branch) - - gd = sb.clone_cached_repo(cached_repo, base_ref) gd.branch(system_branch, base_ref) gd.checkout(system_branch) if not self._checkout_has_systems(gd): - raise BranchRootHasNoSystemsError(root_url, base_ref) - - gd.update_submodules(self.app) - gd.update_remotes() - except BaseException as e: - # Oops. Clean up. - logging.error('Caught exception: %s' % str(e)) - logging.info('Removing half-finished branch %s' % system_branch) - self._remove_branch_dir_safe(ws.root, root_dir) - raise + raise BranchRootHasNoSystemsError(base_ref) def _save_dirty_morphologies(self, loader, sb, morphs): logging.debug('Saving dirty morphologies: start') -- cgit v1.2.1 From 8a003f588136a9f8eda7df876ed6c059dd6658f4 Mon Sep 17 00:00:00 2001 From: Richard Maw Date: Fri, 20 Sep 2013 14:22:31 +0000 Subject: morphlib: Add SystemMetadataDir class This provides access to the /baserock directory as if it were a dict, abstracting away the details of how to get data out of it. The abstraction is useful since it is easier to use than accessing /baserock yourself, and allows the storage format to be changed more easily. Keys with / in may be supported in the future. since there have been discussions about allowing morphologies to be placed in subdirectories. Adding this support would require creating and removing directory components when values are set and deleted respectively. Iterating would require using os.walk instead of glob.iglob, since python doesn't support ** in globs. --- morphlib/__init__.py | 1 + morphlib/systemmetadatadir.py | 87 +++++++++++++++++++++++++++++++++++++ morphlib/systemmetadatadir_tests.py | 75 ++++++++++++++++++++++++++++++++ 3 files changed, 163 insertions(+) create mode 100644 morphlib/systemmetadatadir.py create mode 100644 morphlib/systemmetadatadir_tests.py diff --git a/morphlib/__init__.py b/morphlib/__init__.py index b1e3c7c3..7eb3f975 100644 --- a/morphlib/__init__.py +++ b/morphlib/__init__.py @@ -78,6 +78,7 @@ import sourcepool import stagingarea import stopwatch import sysbranchdir +import systemmetadatadir import tempdir import util import workspace diff --git a/morphlib/systemmetadatadir.py b/morphlib/systemmetadatadir.py new file mode 100644 index 00000000..eac5b446 --- /dev/null +++ b/morphlib/systemmetadatadir.py @@ -0,0 +1,87 @@ +# Copyright (C) 2013 Codethink Limited +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; version 2 of the License. +# +# This program 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 General Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program; if not, write to the Free Software Foundation, Inc., +# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +# +# =*= License: GPL-2 =*= + + +import collections +import glob +import json +import os + + +class SystemMetadataDir(collections.MutableMapping): + + '''An abstraction over the /baserock metadata directory. + + This allows methods of iterating over it, and accessing it like + a dict. + + The /baserock metadata directory contains information about all of + the chunks in a built system. It exists to provide traceability from + the input sources to the output. + + If you create the object with smd = SystemMetadataDir('/baserock') + data = smd['key'] will read /baserock/key.meta and return its JSON + encoded contents as native python objects. + + smd['key'] = data will write data to /baserock/key.meta as JSON + + The key may not have '\0' characters in it since the underlying + system calls don't support embedded NUL bytes. + + The key may not have '/' characters in it since we do not support + morphologies with slashes in their names. + + ''' + + def __init__(self, metadata_path): + collections.MutableMapping.__init__(self) + self._metadata_path = metadata_path + + def _join_path(self, *args): + return os.path.join(self._metadata_path, *args) + + def _raw_path_iter(self): + return glob.iglob(self._join_path('*.meta')) + + @staticmethod + def _check_key(key): + if any(c in key for c in "\0/"): + raise KeyError(key) + + def __getitem__(self, key): + self._check_key(key) + try: + with open(self._join_path('%s.meta' % key), 'r') as f: + return json.load(f) + except IOError: + raise KeyError(key) + + def __setitem__(self, key, value): + self._check_key(key) + with open(self._join_path('%s.meta' % key), 'w') as f: + json.dump(value, f, indent=4, sort_keys=True) + + def __delitem__(self, key): + self._check_key(key) + os.unlink(self._join_path('%s.meta' % key)) + + def __iter__(self): + return (os.path.basename(fn)[:-len('.meta')] + for fn in self._raw_path_iter()) + + def __len__(self): + return len(list(self._raw_path_iter())) diff --git a/morphlib/systemmetadatadir_tests.py b/morphlib/systemmetadatadir_tests.py new file mode 100644 index 00000000..0126f862 --- /dev/null +++ b/morphlib/systemmetadatadir_tests.py @@ -0,0 +1,75 @@ +# Copyright (C) 2013 Codethink Limited +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; version 2 of the License. +# +# This program 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 General Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program; if not, write to the Free Software Foundation, Inc., +# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +# +# =*= License: GPL-2 =*= + + +import operator +import os +import shutil +import tempfile +import unittest + +import morphlib + + +class SystemMetadataDirTests(unittest.TestCase): + + def setUp(self): + self.tempdir = tempfile.mkdtemp() + self.metadatadir = os.path.join(self.tempdir, 'baserock') + os.mkdir(self.metadatadir) + self.smd = morphlib.systemmetadatadir.SystemMetadataDir( + self.metadatadir) + + def tearDown(self): + shutil.rmtree(self.tempdir) + + def test_add_new(self): + self.smd['key'] = {'foo': 'bar'} + self.assertEqual(self.smd['key']['foo'], 'bar') + + def test_replace(self): + self.smd['key'] = {'foo': 'bar'} + self.smd['key'] = {'foo': 'baz'} + self.assertEqual(self.smd['key']['foo'], 'baz') + + def test_remove(self): + self.smd['key'] = {'foo': 'bar'} + del self.smd['key'] + self.assertTrue('key' not in self.smd) + + def test_iterate(self): + self.smd['build-essential'] = "Some data" + self.smd['core'] = "More data" + self.smd['foundation'] = "Yet more data" + self.assertEqual(sorted(self.smd.keys()), + ['build-essential', 'core', 'foundation']) + self.assertEqual(dict(self.smd.iteritems()), + { + 'build-essential': "Some data", + 'core': "More data", + 'foundation': "Yet more data", + }) + + def test_raises_KeyError(self): + self.assertRaises(KeyError, operator.getitem, self.smd, 'key') + + def test_validates_keys(self): + for key in ('foo/bar', 'baz\0quux'): + self.assertRaises(KeyError, operator.getitem, self.smd, key) + self.assertRaises(KeyError, operator.setitem, + self.smd, key, 'value') + self.assertRaises(KeyError, operator.delitem, self.smd, key) -- cgit v1.2.1 From a2468159c731dbcf26dbb6483bcf50b5a81bccd8 Mon Sep 17 00:00:00 2001 From: Richard Maw Date: Thu, 19 Sep 2013 11:16:30 +0000 Subject: B&M: refactor branch-from-image This changes the interface of branch-from-image to only take 1 parameter, the name of the new system branch, as the root repository is loaded from the metadata. This was also what the previous version of branch-from-image did, but that silently ignored the parameter. Given there are not many users of branch-from-image, I felt it was a reasonable change. --- morphlib/plugins/branch_and_merge_new_plugin.py | 104 ++++++++++++++++++++++++ morphlib/plugins/branch_and_merge_plugin.py | 12 +-- tests.as-root/branch-from-image-works.script | 3 +- 3 files changed, 108 insertions(+), 11 deletions(-) diff --git a/morphlib/plugins/branch_and_merge_new_plugin.py b/morphlib/plugins/branch_and_merge_new_plugin.py index 7cd84898..809699eb 100644 --- a/morphlib/plugins/branch_and_merge_new_plugin.py +++ b/morphlib/plugins/branch_and_merge_new_plugin.py @@ -56,6 +56,15 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): arg_synopsis='-- COMMAND [ARGS...]') self.app.add_subcommand('status', self.status, arg_synopsis='') + self.app.add_subcommand('branch-from-image', self.branch_from_image, + arg_synopsis='BRANCH') + group_branch = 'Branching Options' + self.app.settings.string(['metadata-dir'], + 'Set metadata location for branch-from-image' + ' (default: /baserock)', + metavar='DIR', + default='/baserock', + group=group_branch) def disable(self): pass @@ -790,3 +799,98 @@ class SimpleBranchAndMergePlugin(cliapp.Plugin): if not has_uncommitted_changes: self.app.output.write("\nNo repos have outstanding changes.\n") + + def branch_from_image(self, args): + '''Produce a branch of an existing system image. + + Given the metadata specified by --metadata-dir, create a new + branch then petrify it to the state of the commits at the time + the system was built. + + If --metadata-dir is not specified, it defaults to your currently + running system. + + ''' + if len(args) != 1: + raise cliapp.AppException( + "branch-from-image needs exactly 1 argument " + "of the new system branch's name") + system_branch = args[0] + metadata_path = self.app.settings['metadata-dir'] + alias_resolver = morphlib.repoaliasresolver.RepoAliasResolver( + self.app.settings['repo-alias']) + + self._require_git_user_config() + + ws = morphlib.workspace.open('.') + + system, metadata = self._load_system_metadata(metadata_path) + resolved_refs = dict(self._resolve_refs_from_metadata(alias_resolver, + metadata)) + logging.debug('Resolved refs: %r' % resolved_refs) + base_ref = system['sha1'] + # The previous version would fall back to deducing this from the repo + # url and the repo alias resolver, but this does not always work, and + # new systems always have repo-alias in the metadata + root_url = system['repo-alias'] + + lrc, rrc = morphlib.util.new_repo_caches(self.app) + cached_repo = lrc.get_updated_repo(root_url) + + + with self._initializing_system_branch( + ws, root_url, system_branch, cached_repo, base_ref) as (sb, gd): + + # TODO: It's nasty to clone to a sha1 then create a branch + # of that sha1 then check it out, a nicer API may be the + # initial clone not checking out a branch at all, then + # the user creates and checks out their own branches + gd.branch(system_branch, base_ref) + gd.checkout(system_branch) + + loader = morphlib.morphloader.MorphologyLoader() + morphs = self._load_all_sysbranch_morphologies(sb, loader) + + morphs.repoint_refs(sb.root_repository_url, + sb.system_branch_name) + + morphs.petrify_chunks(resolved_refs) + + self._save_dirty_morphologies(loader, sb, morphs.morphologies) + + @staticmethod + def _load_system_metadata(path): + '''Load all metadata in `path` corresponding to a single System. + ''' + + smd = morphlib.systemmetadatadir.SystemMetadataDir(path) + metadata = smd.values() + systems = [md for md in metadata + if 'kind' in md and md['kind'] == 'system'] + + if not systems: + raise cliapp.AppException( + 'Metadata directory does not contain any systems.') + if len(systems) > 1: + raise cliapp.AppException( + 'Metadata directory contains multiple systems.') + system_metadatum = systems[0] + + metadata_cache_id_lookup = dict((md['cache-key'], md) + for md in metadata) + + return system_metadatum, metadata_cache_id_lookup + + @staticmethod + def _resolve_refs_from_metadata(alias_resolver, metadata): + '''Pre-resolve a set of refs from existing metadata. + + Given the metadata, generate a mapping of all the (repo, ref) + pairs defined in the metadata and the commit id they resolved to. + + ''' + for md in metadata.itervalues(): + repourls = set((md['repo-alias'], md['repo'])) + repourls.update(alias_resolver.aliases_from_url(md['repo'])) + for repourl in repourls: + yield ((repourl, md['original_ref']), md['sha1']) diff --git a/morphlib/plugins/branch_and_merge_plugin.py b/morphlib/plugins/branch_and_merge_plugin.py index 37d5e40c..2f8560d0 100644 --- a/morphlib/plugins/branch_and_merge_plugin.py +++ b/morphlib/plugins/branch_and_merge_plugin.py @@ -68,15 +68,9 @@ class BranchAndMergePlugin(cliapp.Plugin): self.app.add_subcommand('build', self.build, arg_synopsis='SYSTEM') self.app.add_subcommand('old-status', self.status) - self.app.add_subcommand('branch-from-image', self.branch_from_image, - arg_synopsis='REPO BRANCH') - group_branch = 'Branching Options' - self.app.settings.string(['metadata-dir'], - 'Set metadata location for branch-from-image' - ' (default: /baserock)', - metavar='DIR', - default='/baserock', - group=group_branch) + self.app.add_subcommand('old-branch-from-image', + self.branch_from_image, + arg_synopsis='REPO BRANCH') # Advanced commands self.app.add_subcommand('old-foreach', self.foreach, diff --git a/tests.as-root/branch-from-image-works.script b/tests.as-root/branch-from-image-works.script index 9f82f629..942301e8 100755 --- a/tests.as-root/branch-from-image-works.script +++ b/tests.as-root/branch-from-image-works.script @@ -48,8 +48,7 @@ git commit --quiet -m 'Make hello say goodbye' workspace="$DATADIR/workspace" "$SRCDIR/scripts/test-morph" init "$workspace" cd "$workspace" -"$SRCDIR/scripts/test-morph" branch-from-image \ - test:morphs mybranch \ +"$SRCDIR/scripts/test-morph" branch-from-image mybranch \ --metadata-dir="$extracted/baserock" cd mybranch/test:morphs grep -qFe "$hello_chunk_commit" hello-stratum.morph -- cgit v1.2.1