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
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
#!/usr/bin/python
# -*- coding: utf-8 -*-
"""
Ansible module to manage symbolic link alternatives.
(c) 2014, Gabe Mulley <gabe.mulley@gmail.com>
(c) 2015, David Wittman <dwittman@gmail.com>
This file is part of Ansible
Ansible 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, either version 3 of the License, or
(at your option) any later version.
Ansible 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 Ansible. If not, see <http://www.gnu.org/licenses/>.
"""
ANSIBLE_METADATA = {'status': ['preview'],
'supported_by': 'community',
'version': '1.0'}
DOCUMENTATION = '''
---
module: alternatives
short_description: Manages alternative programs for common commands
description:
- Manages symbolic links using the 'update-alternatives' tool
- Useful when multiple programs are installed but provide similar functionality (e.g. different editors).
version_added: "1.6"
author:
- "David Wittman (@DavidWittman)"
- "Gabe Mulley (@mulby)"
options:
name:
description:
- The generic name of the link.
required: true
path:
description:
- The path to the real executable that the link should point to.
required: true
link:
description:
- The path to the symbolic link that should point to the real executable.
- This option is required on RHEL-based distributions
required: false
priority:
description:
- The priority of the alternative
required: false
default: 50
version_added: "2.2"
requirements: [ update-alternatives ]
'''
EXAMPLES = '''
- name: correct java version selected
alternatives:
name: java
path: /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java
- name: alternatives link created
alternatives:
name: hadoop-conf
link: /etc/hadoop/conf
path: /etc/hadoop/conf.ansible
- name: make java 32 bit an alternative with low priority
alternatives:
name: java
path: /usr/lib/jvm/java-7-openjdk-i386/jre/bin/java
priority: -10
'''
import re
from ansible.module_utils.basic import *
from ansible.module_utils.pycompat24 import get_exception
def main():
module = AnsibleModule(
argument_spec = dict(
name = dict(required=True),
path = dict(required=True, type='path'),
link = dict(required=False, type='path'),
priority = dict(required=False, type='int',
default=50),
),
supports_check_mode=True,
)
params = module.params
name = params['name']
path = params['path']
link = params['link']
priority = params['priority']
UPDATE_ALTERNATIVES = module.get_bin_path('update-alternatives',True)
current_path = None
all_alternatives = []
# Run `update-alternatives --display <name>` to find existing alternatives
(rc, display_output, _) = module.run_command(
['env', 'LC_ALL=C', UPDATE_ALTERNATIVES, '--display', name]
)
if rc == 0:
# Alternatives already exist for this link group
# Parse the output to determine the current path of the symlink and
# available alternatives
current_path_regex = re.compile(r'^\s*link currently points to (.*)$',
re.MULTILINE)
alternative_regex = re.compile(r'^(\/.*)\s-\spriority', re.MULTILINE)
current_path = current_path_regex.search(display_output).group(1)
all_alternatives = alternative_regex.findall(display_output)
if not link:
# Read the current symlink target from `update-alternatives --query`
# in case we need to install the new alternative before setting it.
#
# This is only compatible on Debian-based systems, as the other
# alternatives don't have --query available
rc, query_output, _ = module.run_command(
['env', 'LC_ALL=C', UPDATE_ALTERNATIVES, '--query', name]
)
if rc == 0:
for line in query_output.splitlines():
if line.startswith('Link:'):
link = line.split()[1]
break
if current_path != path:
if module.check_mode:
module.exit_json(changed=True, current_path=current_path)
try:
# install the requested path if necessary
if path not in all_alternatives:
if not link:
module.fail_json(msg="Needed to install the alternative, but unable to do so as we are missing the link")
module.run_command(
[UPDATE_ALTERNATIVES, '--install', link, name, path, str(priority)],
check_rc=True
)
# select the requested path
module.run_command(
[UPDATE_ALTERNATIVES, '--set', name, path],
check_rc=True
)
module.exit_json(changed=True)
except subprocess.CalledProcessError:
e = get_exception()
module.fail_json(msg=str(dir(cpe)))
else:
module.exit_json(changed=False)
if __name__ == '__main__':
main()
|
