ansible/library/network/get_url
Joshua Lund 20489f1346 * Updated SHA-256 functionality in the get_url module
(fixes issue #4277)

* The sha256sum error message now displays the invalid
  destination checksum if it doesn't match the one that
  is specified in the arguments. This is useful for
  debugging purposes.

* Non-alphanumeric characters, including the infamous
  Unicode zero-width space, are removed from the sha256sum
  argument prior to the check.
2013-09-27 14:37:21 -06:00

327 lines
11 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
# (c) 2012, Jan-Piet Mens <jpmens () 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/>.
#
# see examples/playbooks/get_url.yml
import shutil
import datetime
import re
import tempfile
DOCUMENTATION = '''
---
module: get_url
short_description: Downloads files from HTTP, HTTPS, or FTP to node
description:
- Downloads files from HTTP, HTTPS, or FTP to the remote server. The remote
server I(must) have direct access to the remote resource.
- By default, if an environment variable C(<protocol>_proxy) is set on
the target host, requests will be sent through that proxy. This
behaviour can be overridden by setting a variable for this task
(see `setting the environment
<http://www.ansibleworks.com/docs/playbooks2.html#setting-the-environment-and-working-with-proxies>`_),
or by using the use_proxy option.
version_added: "0.6"
options:
url:
description:
- HTTP, HTTPS, or FTP URL in the form (http|https|ftp)://[user[:pass]]@host.domain[:port]/path
required: true
default: null
aliases: []
dest:
description:
- absolute path of where to download the file to.
- If I(dest) is a directory, the basename of the file on the remote server will be used. If a directory, C(force=yes) must also be set.
required: true
default: null
force:
description:
- If C(yes), will download the file every time and replace the
file if the contents change. If C(no), the file will only be downloaded if
the destination does not exist. Generally should be C(yes) only for small
local files. Prior to 0.6, this module behaved as if C(yes) was the default.
version_added: "0.7"
required: false
choices: [ "yes", "no" ]
default: "no"
aliases: [ "thirsty" ]
sha256sum:
description:
- If a SHA-256 checksum is passed to this parameter, the digest of the
destination file will be calculated after it is downloaded to ensure
its integrity and verify that the transfer completed successfully.
version_added: "1.3"
required: false
default: null
use_proxy:
description:
- if C(no), it will not use a proxy, even if one is defined in
an environment variable on the target hosts.
required: false
default: 'yes'
choices: ['yes', 'no']
others:
description:
- all arguments accepted by the M(file) module also work here
required: false
notes:
- This module doesn't yet support configuration for proxies.
# informational: requirements for nodes
requirements: [ urllib2, urlparse ]
author: Jan-Piet Mens
'''
EXAMPLES='''
- name: download foo.conf
get_url: url=http://example.com/path/file.conf dest=/etc/foo.conf mode=0440
- name: download file with sha256 check
get_url: url=http://example.com/path/file.conf dest=/etc/foo.conf sha256sum=b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c
'''
try:
import hashlib
HAS_HASHLIB=True
except ImportError:
HAS_HASHLIB=False
try:
import urllib2
HAS_URLLIB2 = True
except ImportError:
HAS_URLLIB2 = False
try:
import urlparse
import socket
HAS_URLPARSE = True
except ImportError:
HAS_URLPARSE=False
# ==============================================================
# url handling
def url_filename(url):
fn = os.path.basename(urlparse.urlsplit(url)[2])
if fn == '':
return 'index.html'
return fn
def url_do_get(module, url, dest, use_proxy):
"""
Get url and return request and info
Credits: http://stackoverflow.com/questions/7006574/how-to-download-file-from-ftp
"""
USERAGENT = 'ansible-httpget'
info = dict(url=url, dest=dest)
r = None
handlers = []
parsed = urlparse.urlparse(url)
if '@' in parsed[1]:
credentials, netloc = parsed[1].split('@', 1)
if ':' in credentials:
username, password = credentials.split(':', 1)
else:
username = credentials
password = ''
parsed = list(parsed)
parsed[1] = netloc
passman = urllib2.HTTPPasswordMgrWithDefaultRealm()
# this creates a password manager
passman.add_password(None, netloc, username, password)
# because we have put None at the start it will always
# use this username/password combination for urls
# for which `theurl` is a super-url
authhandler = urllib2.HTTPBasicAuthHandler(passman)
# create the AuthHandler
handlers.append(authhandler)
#reconstruct url without credentials
url = urlparse.urlunparse(parsed)
if not use_proxy:
proxyhandler = urllib2.ProxyHandler({})
handlers.append(proxyhandler)
opener = urllib2.build_opener(*handlers)
urllib2.install_opener(opener)
request = urllib2.Request(url)
request.add_header('User-agent', USERAGENT)
if os.path.exists(dest) and not module.params['force']:
t = datetime.datetime.utcfromtimestamp(os.path.getmtime(dest))
tstamp = t.strftime('%a, %d %b %Y %H:%M:%S +0000')
request.add_header('If-Modified-Since', tstamp)
try:
r = urllib2.urlopen(request)
info.update(r.info())
info.update(dict(msg="OK (%s bytes)" % r.headers.get('Content-Length', 'unknown'), status=200))
except urllib2.HTTPError, e:
# Must not fail_json() here so caller can handle HTTP 304 unmodified
info.update(dict(msg=str(e), status=e.code))
return r, info
except urllib2.URLError, e:
code = getattr(e, 'code', -1)
module.fail_json(msg="Request failed: %s" % str(e), status_code=code)
return r, info
def url_get(module, url, dest, use_proxy):
"""
Download url and store at dest.
If dest is a directory, determine filename from url.
Return (tempfile, info about the request)
"""
req, info = url_do_get(module, url, dest, use_proxy)
# TODO: should really handle 304, but how? src file could exist (and be newer) but empty
if info['status'] == 304:
module.exit_json(url=url, dest=dest, changed=False, msg=info.get('msg', ''))
# create a temporary file and copy content to do md5-based replacement
if info['status'] != 200:
module.fail_json(msg="Request failed", status_code=info['status'], response=info['msg'], url=url, dest=dest)
fd, tempname = tempfile.mkstemp()
f = os.fdopen(fd, 'wb')
try:
shutil.copyfileobj(req, f)
except Exception, err:
os.remove(tempname)
module.fail_json(msg="failed to create temporary content file: %s" % str(err))
f.close()
req.close()
return tempname, info
# ==============================================================
# main
def main():
# does this really happen on non-ancient python?
if not HAS_URLLIB2:
module.fail_json(msg="urllib2 is not installed")
if not HAS_URLPARSE:
module.fail_json(msg="urlparse is not installed")
module = AnsibleModule(
# not checking because of daisy chain to file module
argument_spec = dict(
url = dict(required=True),
dest = dict(required=True),
force = dict(default='no', aliases=['thirsty'], type='bool'),
sha256sum = dict(default=''),
use_proxy = dict(default='yes', type='bool')
),
add_file_common_args=True
)
url = module.params['url']
dest = os.path.expanduser(module.params['dest'])
force = module.params['force']
sha256sum = module.params['sha256sum']
use_proxy = module.params['use_proxy']
if os.path.isdir(dest):
dest = os.path.join(dest, url_filename(url))
if not force:
if os.path.exists(dest):
module.exit_json(msg="file already exists", dest=dest, url=url, changed=False)
# download to tmpsrc
tmpsrc, info = url_get(module, url, dest, use_proxy)
md5sum_src = None
md5sum_dest = None
# raise an error if there is no tmpsrc file
if not os.path.exists(tmpsrc):
os.remove(tmpsrc)
module.fail_json(msg="Request failed", status_code=info['status'], response=info['msg'])
if not os.access(tmpsrc, os.R_OK):
os.remove(tmpsrc)
module.fail_json( msg="Source %s not readable" % (tmpsrc))
md5sum_src = module.md5(tmpsrc)
# check if there is no dest file
if os.path.exists(dest):
# raise an error if copy has no permission on dest
if not os.access(dest, os.W_OK):
os.remove(tmpsrc)
module.fail_json( msg="Destination %s not writable" % (dest))
if not os.access(dest, os.R_OK):
os.remove(tmpsrc)
module.fail_json( msg="Destination %s not readable" % (dest))
md5sum_dest = module.md5(dest)
else:
if not os.access(os.path.dirname(dest), os.W_OK):
os.remove(tmpsrc)
module.fail_json( msg="Destination %s not writable" % (os.path.dirname(dest)))
if md5sum_src != md5sum_dest:
try:
shutil.copyfile(tmpsrc, dest)
except Exception, err:
os.remove(tmpsrc)
module.fail_json(msg="failed to copy %s to %s: %s" % (tmpsrc, dest, str(err)))
changed = True
else:
changed = False
# Check the digest of the destination file and ensure that it matches the
# sha256sum parameter if it is present
if sha256sum != '':
# Remove any non-alphanumeric characters, including the infamous
# Unicode zero-width space
stripped_sha256sum = re.sub(r'\W+', '', sha256sum)
if not HAS_HASHLIB:
os.remove(dest)
module.fail_json(msg="The sha256sum parameter requires hashlib, which is available in Python 2.5 and higher")
else:
destination_checksum = module.sha256(dest)
if stripped_sha256sum != destination_checksum:
os.remove(dest)
module.fail_json(msg="The SHA-256 checksum for %s did not match %s; it was %s." % (dest, sha256sum, destination_checksum))
os.remove(tmpsrc)
# allow file attribute changes
module.params['path'] = dest
file_args = module.load_file_common_arguments(module.params)
file_args['path'] = dest
changed = module.set_file_attributes_if_different(file_args, changed)
# Mission complete
module.exit_json(url=url, dest=dest, src=tmpsrc, md5sum=md5sum_src,
sha256sum=sha256sum, changed=changed, msg=info.get('msg', ''))
# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()