Move VyOS charm from descriptor repo to here
Signed-off-by: Philip Joseph <philip.joseph@riftio.com>
diff --git a/builds/VyOS-proxy/lib/charms/layer/execd.py b/builds/VyOS-proxy/lib/charms/layer/execd.py
new file mode 100644
index 0000000..30574190
--- /dev/null
+++ b/builds/VyOS-proxy/lib/charms/layer/execd.py
@@ -0,0 +1,138 @@
+# Copyright 2014-2016 Canonical Limited.
+#
+# This file is part of layer-basic, the reactive base layer for Juju.
+#
+# charm-helpers is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# charm-helpers 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 charm-helpers. If not, see <http://www.gnu.org/licenses/>.
+
+# This module may only import from the Python standard library.
+import os
+import sys
+import subprocess
+import time
+
+'''
+execd/preinstall
+
+It is often necessary to configure and reconfigure machines
+after provisioning, but before attempting to run the charm.
+Common examples are specialized network configuration, enabling
+of custom hardware, non-standard disk partitioning and filesystems,
+adding secrets and keys required for using a secured network.
+
+The reactive framework's base layer invokes this mechanism as
+early as possible, before any network access is made or dependencies
+unpacked or non-standard modules imported (including the charms.reactive
+framework itself).
+
+Operators needing to use this functionality may branch a charm and
+create an exec.d directory in it. The exec.d directory in turn contains
+one or more subdirectories, each of which contains an executable called
+charm-pre-install and any other required resources. The charm-pre-install
+executables are run, and if successful, state saved so they will not be
+run again.
+
+ $CHARM_DIR/exec.d/mynamespace/charm-pre-install
+
+An alternative to branching a charm is to compose a new charm that contains
+the exec.d directory, using the original charm as a layer,
+
+A charm author could also abuse this mechanism to modify the charm
+environment in unusual ways, but for most purposes it is saner to use
+charmhelpers.core.hookenv.atstart().
+'''
+
+
+def default_execd_dir():
+ return os.path.join(os.environ['CHARM_DIR'], 'exec.d')
+
+
+def execd_module_paths(execd_dir=None):
+ """Generate a list of full paths to modules within execd_dir."""
+ if not execd_dir:
+ execd_dir = default_execd_dir()
+
+ if not os.path.exists(execd_dir):
+ return
+
+ for subpath in os.listdir(execd_dir):
+ module = os.path.join(execd_dir, subpath)
+ if os.path.isdir(module):
+ yield module
+
+
+def execd_submodule_paths(command, execd_dir=None):
+ """Generate a list of full paths to the specified command within exec_dir.
+ """
+ for module_path in execd_module_paths(execd_dir):
+ path = os.path.join(module_path, command)
+ if os.access(path, os.X_OK) and os.path.isfile(path):
+ yield path
+
+
+def execd_sentinel_path(submodule_path):
+ module_path = os.path.dirname(submodule_path)
+ execd_path = os.path.dirname(module_path)
+ module_name = os.path.basename(module_path)
+ submodule_name = os.path.basename(submodule_path)
+ return os.path.join(execd_path,
+ '.{}_{}.done'.format(module_name, submodule_name))
+
+
+def execd_run(command, execd_dir=None, stop_on_error=True, stderr=None):
+ """Run command for each module within execd_dir which defines it."""
+ if stderr is None:
+ stderr = sys.stdout
+ for submodule_path in execd_submodule_paths(command, execd_dir):
+ # Only run each execd once. We cannot simply run them in the
+ # install hook, as potentially storage hooks are run before that.
+ # We cannot rely on them being idempotent.
+ sentinel = execd_sentinel_path(submodule_path)
+ if os.path.exists(sentinel):
+ continue
+
+ try:
+ subprocess.check_call([submodule_path], stderr=stderr,
+ universal_newlines=True)
+ with open(sentinel, 'w') as f:
+ f.write('{} ran successfully {}\n'.format(submodule_path,
+ time.ctime()))
+ f.write('Removing this file will cause it to be run again\n')
+ except subprocess.CalledProcessError as e:
+ # Logs get the details. We can't use juju-log, as the
+ # output may be substantial and exceed command line
+ # length limits.
+ print("ERROR ({}) running {}".format(e.returncode, e.cmd),
+ file=stderr)
+ print("STDOUT<<EOM", file=stderr)
+ print(e.output, file=stderr)
+ print("EOM", file=stderr)
+
+ # Unit workload status gets a shorter fail message.
+ short_path = os.path.relpath(submodule_path)
+ block_msg = "Error ({}) running {}".format(e.returncode,
+ short_path)
+ try:
+ subprocess.check_call(['status-set', 'blocked', block_msg],
+ universal_newlines=True)
+ if stop_on_error:
+ sys.exit(0) # Leave unit in blocked state.
+ except Exception:
+ pass # We care about the exec.d/* failure, not status-set.
+
+ if stop_on_error:
+ sys.exit(e.returncode or 1) # Error state for pre-1.24 Juju
+
+
+def execd_preinstall(execd_dir=None):
+ """Run charm-pre-install for each module within execd_dir."""
+ execd_run('charm-pre-install', execd_dir=execd_dir)