Add a class to wrap the OSTree API

Change-Id: I6c193597f136d1a0f4af14f3fd670c01f9ae2875

4 files changed, 189 insertions, 0 deletions

diff --git a/morphlib/__init__.py b/morphlib/__init__.py
index 0c9284d8..e2641402 100644
--- a/morphlib/__init__.py
+++ b/morphlib/__init__.py
@@ -72,6 +72,7 @@ import morphologyfinder
 import morphology
 import morphloader
 import morphset
+import ostree
 import remoteartifactcache
 import remoterepocache
 import repoaliasresolver
diff --git a/morphlib/app.py b/morphlib/app.py
index ac9d70e7..51a998b7 100644
--- a/morphlib/app.py
+++ b/morphlib/app.py
@@ -128,6 +128,15 @@ class Morph(cliapp.Application):
                              'supported at this time.',
                              default='overlayfs',
                              group=group_advanced)
+        self.settings.string(['ostree-repo-mode'],
+                             'Mode for OSTree artifact cache repository. If '
+                             'things will need to pull from your cache, this '
+                             'needs to be "archive_z2". Otherwise use '
+                             '"bare". Note that archive_z2 will cause things '
+                             'involving the artifact cache (building and/or '
+                             'deploying) to be slow.',
+                             default='bare',
+                             group=group_advanced)
 
         group_build = 'Build Options'
         self.settings.integer(['max-jobs'],
diff --git a/morphlib/ostree.py b/morphlib/ostree.py
new file mode 100644
index 00000000..ed2c59da
--- /dev/null
+++ b/morphlib/ostree.py
@@ -0,0 +1,178 @@
+# Copyright (C) 2013-2015  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, see <http://www.gnu.org/licenses/>.
+#
+# =*= License: GPL-2 =*=
+
+
+from gi.repository import OSTree
+from gi.repository import Gio
+from gi.repository import GLib
+
+import os
+import logging
+
+
+class OSTreeRepo(object):
+
+    """Class to wrap the OSTree API."""
+
+    G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS = Gio.FileQueryInfoFlags(1)
+    OSTREE_GIO_FAST_QUERYINFO = (
+        'standard::name,'
+        'standard::type,'
+        'standard::size,'
+        'standard::is-symlink,'
+        'standard::symlink-target,'
+        'unix::device,'
+        'unix::inode,'
+        'unix::mode,'
+        'unix::uid,'
+        'unix::gid,'
+        'unix::rdev')
+    
+    def __init__(self, path, disable_fsync=True, mode='bare'):
+        self.path = path
+        self.repo = self._open_repo(path, disable_fsync, mode)
+
+    def _open_repo(self, path, disable_fsync=True, mode='bare'):
+        """Create and open and OSTree.Repo, and return it."""
+        repo_dir = Gio.file_new_for_path(path)
+        repo = OSTree.Repo.new(repo_dir)
+        logging.debug('using %s' % mode)
+        if mode == 'bare':
+            mode = OSTree.RepoMode.BARE
+        elif mode == 'archive_z2':
+            mode = OSTree.RepoMode.ARCHIVE_Z2
+        else:
+            raise Exception('Mode %s is not supported' % mode)
+
+        try:
+            repo.open(None)
+            logging.debug('opened')
+        except GLib.GError:
+            if not os.path.exists(path):
+                os.makedirs(path)
+            logging.debug('failed to open, creating')
+            repo.create(mode, None)
+        repo.set_disable_fsync(disable_fsync)
+        return repo
+    
+    def refsdir(self):
+        """Return the abspath to the refs/heads directory in the repo."""
+        return os.path.join(os.path.abspath(self.path), 'refs/heads')
+
+    def touch_ref(self, ref):
+        """Update the mtime of a ref file in repo/refs/heads."""
+        os.utime(os.path.join(self.refsdir(), ref), None)
+
+    def resolve_rev(self, branch, allow_noent=True):
+        """Return the SHA256 corresponding to 'branch'."""
+        return self.repo.resolve_rev(branch, allow_noent)[1]
+    
+    def read_commit(self, branch):
+        """Return an OSTree.RepoFile representing a committed tree."""
+        return self.repo.read_commit(branch, None)[1]
+    
+    def query_info(self, file_object):
+        """Quickly return a Gio.FileInfo for file_object."""
+        return file_object.query_info(self.OSTREE_GIO_FAST_QUERYINFO,
+                                      self.G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
+                                      None)
+    
+    def checkout(self, branch, destdir):
+        """Checkout branch into destdir."""
+        checkout_path = destdir
+        if not os.path.exists(checkout_path):
+            os.makedirs(checkout_path)
+        checkout = Gio.file_new_for_path(checkout_path)
+    
+        commit = self.read_commit(branch)
+        commit_info = self.query_info(commit)
+        self.repo.checkout_tree(OSTree.RepoCheckoutMode.NONE,
+                                OSTree.RepoCheckoutOverwriteMode.UNION_FILES,
+                                checkout, commit,commit_info, None)
+
+    def commit(self, subject, srcdir, branch, body=''):
+        """Commit the contents of 'srcdir' to 'branch'.
+
+        The subject parameter is the title of the commit message, and the
+        body parameter is the body of the commit message.
+
+        """
+        self.repo.prepare_transaction(None)
+        parent = self.resolve_rev(branch)
+        mtree = OSTree.MutableTree()
+        src = Gio.file_new_for_path(srcdir)
+        self.repo.write_directory_to_mtree(src, mtree, None, None)
+        root = self.repo.write_mtree(mtree, None)[1]
+        checksum = self.repo.write_commit(parent, subject, body,
+                                          None, root, None)[1]
+        self.repo.transaction_set_ref(None, branch, checksum)
+        stats = self.repo.commit_transaction(None)
+
+    def cat_file(self, ref, path):
+        """Return the file descriptor of path at ref."""
+        commit = self.read_commit(ref)
+        relative = commit.resolve_relative_path(path)
+        ret, content, etag = relative.load_contents()
+        return content
+
+    def list_refs(self, ref=None, resolved=False):
+        """Return a list of all refs in the repo."""
+        if ref:
+            refs = self.repo.list_refs(ref)[1]
+        else:
+            refs = self.repo.list_refs()[1]
+        if not resolved:
+            return refs.keys()
+        return refs
+
+    def delete_ref(self, ref):
+        """Remove refspec from the repo."""
+        if not self.list_refs(ref):
+            raise Exception("Failed to delete ref, it doesn't exist")
+        self.repo.set_ref_immediate(None, ref, None, None)
+
+    def prune(self):
+        """Remove unreachable objects from the repo."""
+        depth = -1 # no recursion limit
+        return self.repo.prune(OSTree.RepoPruneFlags.REFS_ONLY, depth, None)
+
+    def add_remote(self, name, url):
+        """Add a remote with a given name and url."""
+        options_type = GLib.VariantType.new('a{sv}')
+        options_builder = GLib.VariantBuilder.new(options_type)
+        options = options_builder.end()
+        self.repo.remote_add(name, url, options, None)
+
+    def remove_remote(self, name):
+        """Remove a remote with a given name."""
+        self.repo.remote_delete(name, None)
+
+    def get_remote_url(self, name):
+        """Return the URL for a remote."""
+        return self.repo.remote_get_url(name)[1]
+
+    def list_remotes(self):
+        """Return a list of all remotes for this repo."""
+        return self.repo.remote_list()
+
+    def has_remote(self, name):
+        """Return True if name is a remote for the repo."""
+        return name in self.list_remotes()
+
+    def pull(self, refs, remote):
+        """Pull ref from remote into the local repo."""
+        flags = OSTree.RepoPullFlags.NONE
+        self.repo.pull(remote, refs, flags, None, None)
diff --git a/without-test-modules b/without-test-modules
index caf10c8b..c3e7f5a2 100644
--- a/without-test-modules
+++ b/without-test-modules
@@ -54,3 +54,4 @@ distbuild/timer_event_source.py
 distbuild/worker_build_scheduler.py
 # Not unit tested, since it needs a full system branch
 morphlib/buildbranch.py
+morphlib/ostree.py