Sync with alternatives charmhelpers, installed ceph.conf as alternative for charm co-existence

hooks/charmhelpers/contrib/openstack/alternatives.py

@@ -0,0 +1,17 @@
+''' Helper for managing alternatives for file conflict resolution '''
+
+import subprocess
+import shutil
+import os
+
+
+def install_alternative(name, target, source, priority=50):
+    ''' Install alternative configuration '''
+    if (os.path.exists(target) and not os.path.islink(target)):
+        # Move existing file/directory away before installing
+        shutil.move(target, '{}.bak'.format(target))
+    cmd = [
+        'update-alternatives', '--force', '--install',
+        target, name, source, str(priority)
+    ]
+    subprocess.check_call(cmd)

hooks/charmhelpers/fetch/bzrurl.py

@@ -0,0 +1,49 @@
+import os
+from charmhelpers.fetch import (
+    BaseFetchHandler,
+    UnhandledSource
+)
+from charmhelpers.core.host import mkdir
+
+try:
+    from bzrlib.branch import Branch
+except ImportError:
+    from charmhelpers.fetch import apt_install
+    apt_install("python-bzrlib")
+    from bzrlib.branch import Branch
+
+class BzrUrlFetchHandler(BaseFetchHandler):
+    """Handler for bazaar branches via generic and lp URLs"""
+    def can_handle(self, source):
+        url_parts = self.parse_url(source)
+        if url_parts.scheme not in ('bzr+ssh', 'lp'):
+            return False
+        else:
+            return True
+
+    def branch(self, source, dest):
+        url_parts = self.parse_url(source)
+        # If we use lp:branchname scheme we need to load plugins
+        if not self.can_handle(source):
+            raise UnhandledSource("Cannot handle {}".format(source))
+        if url_parts.scheme == "lp":
+            from bzrlib.plugin import load_plugins
+            load_plugins()
+        try:
+            remote_branch = Branch.open(source)
+            remote_branch.bzrdir.sprout(dest).open_branch()
+        except Exception as e:
+            raise e
+
+    def install(self, source):
+        url_parts = self.parse_url(source)
+        branch_name = url_parts.path.strip("/").split("/")[-1]
+        dest_dir = os.path.join(os.environ.get('CHARM_DIR'), "fetched", branch_name)
+        if not os.path.exists(dest_dir):
+            mkdir(dest_dir, perms=0755)
+        try:
+            self.branch(source, dest_dir)
+        except OSError as e:
+            raise UnhandledSource(e.strerror)
+        return dest_dir
+