1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
|
#!/usr/bin/python
#
# Fetch and run user-data from EC2
# Copyright (C) 2008-2009 Canonical Ltd.
#
# Author: Soren Hansen <soren@canonical.com>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 3, as
# published by the Free Software Foundation.
#
# 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/>.
#
import email
import os
import subprocess
import tempfile
import ec2init
content_type_handlers = { 'text/x-shellscript' : handle_shell_script,
'text/x-ebs-mount-description' : handle_ebs_mount_description }
def main():
ec2 = ec2init.EC2Init()
user_data = ec2.get_user_data()
msg = email.message_from_string(user_data)
handle_part(msg)
def handle_part(part):
if part.is_multipart():
for p in part.get_payload():
handle_part(p)
else:
if part.get_content_type() in content_type_handlers:
content_type_handlers[part.get_content_type](part.get_payload())
return
handle_unknown_payload(part.get_payload())
def handle_unknown_payload(payload):
# Try to detect magic
if payload.startswith('#!'):
content_type_handlers['text/x-shellscript'](payload)
def handle_ebs_mount_description(payload):
(volume_description, path) = payload.split(':')
(identifier_type, identifier) = volume_description.split('=')
if identifier_type == 'device':
device = identifier
# Perhaps some day the volume id -> device path mapping
# will be exposed through meta-data.
# elif identifier_type == 'volume':
# device = extract_device_name_from_meta_data
else:
return
def handle_shell_script(payload):
(fd, path) = tempfile.mkstemp()
fp = os.fdopen(fd, 'a')
fp.write(payload)
fp.close()
os.chmod(path, 0700)
# Run the user data script and pipe its output to logger
user_data_process = subprocess.Popen([path], stdout=subprocess.PIPE)
logger_process = subprocess.Popen(['logger', '-t', 'user-data'], stdin=user_data_process.stdout)
logger_process.communicate()
os.unlink(path)
if __name__ == '__main__':
main()
|
