cli: Add clean and status subcommands

The 'cloud-init clean' command allows a user or script to clear cloud-init
artifacts from the system so that cloud-init sees the system as
unconfigured upon reboot. Optional parameters can be provided to remove
cloud-init logs and reboot after clean.

The 'cloud-init status' command allows the user or script to check whether
cloud-init has finished all configuration stages and whether errors
occurred. An optional --wait argument will poll on a 0.25 second interval
until cloud-init configuration is complete. The benefit here is scripts
can block on cloud-init completion before performing post-config tasks.

1 files changed, 102 insertions, 0 deletions

diff --git a/cloudinit/cmd/clean.py b/cloudinit/cmd/clean.py
new file mode 100644
index 00000000..81797b1c
--- /dev/null
+++ b/cloudinit/cmd/clean.py
@@ -0,0 +1,102 @@
+# Copyright (C) 2017 Canonical Ltd.
+#
+# This file is part of cloud-init. See LICENSE file for license information.
+
+"""Define 'clean' utility and handler as part of cloud-init commandline."""
+
+import argparse
+import os
+import sys
+
+from cloudinit.stages import Init
+from cloudinit.util import (
+    ProcessExecutionError, chdir, del_dir, del_file, get_config_logfiles, subp)
+
+
+def error(msg):
+    sys.stderr.write("ERROR: " + msg + "\n")
+
+
+def get_parser(parser=None):
+    """Build or extend an arg parser for clean utility.
+
+    @param parser: Optional existing ArgumentParser instance representing the
+        clean subcommand which will be extended to support the args of
+        this utility.
+
+    @returns: ArgumentParser with proper argument configuration.
+    """
+    if not parser:
+        parser = argparse.ArgumentParser(
+            prog='clean',
+            description=('Remove logs and artifacts so cloud-init re-runs on '
+                         'a clean system'))
+    parser.add_argument(
+        '-l', '--logs', action='store_true', default=False, dest='remove_logs',
+        help='Remove cloud-init logs.')
+    parser.add_argument(
+        '-r', '--reboot', action='store_true', default=False,
+        help='Reboot system after logs are cleaned so cloud-init re-runs.')
+    parser.add_argument(
+        '-s', '--seed', action='store_true', default=False, dest='remove_seed',
+        help='Remove cloud-init seed directory /var/lib/cloud/seed.')
+    return parser
+
+
+def remove_artifacts(remove_logs, remove_seed=False):
+    """Helper which removes artifacts dir and optionally log files.
+
+    @param: remove_logs: Boolean. Set True to delete the cloud_dir path. False
+        preserves them.
+    @param: remove_seed: Boolean. Set True to also delete seed subdir in
+        paths.cloud_dir.
+    @returns: 0 on success, 1 otherwise.
+    """
+    init = Init(ds_deps=[])
+    init.read_cfg()
+    if remove_logs:
+        for log_file in get_config_logfiles(init.cfg):
+            del_file(log_file)
+
+    if not os.path.isdir(init.paths.cloud_dir):
+        return 0  # Artifacts dir already cleaned
+    with chdir(init.paths.cloud_dir):
+        for path in os.listdir('.'):
+            if path == 'seed' and not remove_seed:
+                continue
+            try:
+                if os.path.isdir(path):
+                    del_dir(path)
+                else:
+                    del_file(path)
+            except OSError as e:
+                error('Could not remove {0}: {1}'.format(path, str(e)))
+                return 1
+    return 0
+
+
+def handle_clean_args(name, args):
+    """Handle calls to 'cloud-init clean' as a subcommand."""
+    exit_code = remove_artifacts(args.remove_logs, args.remove_seed)
+    if exit_code == 0 and args.reboot:
+        cmd = ['shutdown', '-r', 'now']
+        try:
+            subp(cmd, capture=False)
+        except ProcessExecutionError as e:
+            error(
+                'Could not reboot this system using "{0}": {1}'.format(
+                    cmd, str(e)))
+            exit_code = 1
+    return exit_code
+
+
+def main():
+    """Tool to collect and tar all cloud-init related logs."""
+    parser = get_parser()
+    sys.exit(handle_clean_args('clean', parser.parse_args()))
+
+
+if __name__ == '__main__':
+    main()
+
+# vi: ts=4 expandtab