vyos_config: print compare command result in diff mode

[hitsumabushi]

SUMMARY

• print diff with vyos_config
  • as diff, use output of compare command
• example

  TASK [vyos : config example]  
  *******************************************************************************************************************************************************************
  [edit firewall name to_gslb_filter]
  +rule 7 {
  +    action drop
  +    destination {
  +        address 192.168.10.1
  +        port 23
  +    }
  +    protocol tcp
  +}
  

ISSUE TYPE

• Feature Pull Request

COMPONENT NAME

vyos_config module

ANSIBLE VERSION

I checked current devel branch. : https://github.com/ansible/ansible/tree/d7c3d5501bdc7482a330fb7b29ad8dd7ed3683b6

$ ansible --version
ansible 2.7.0.dev0
  config file = /home/hitsu/work/src/github.sakura.codes/iot-pf/router-conf-ansible/ansible.cfg
  configured module search path = ['/home/hitsu/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']                                                                                                  
  ansible python module location = /home/hitsu/.pyenv/versions/3.6.2/envs/3.6_global/lib/python3.6/site-packages/ansible                                                                                          
  executable location = /home/hitsu/.pyenv/versions/global/bin/ansible
  python version = 3.6.2 (default, Nov 23 2017, 16:58:38) [GCC 7.2.0]

[ansibot]

cc @Qalthos @Qalthos @samdoran
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[ganeshrn]

Is there a specific reason for moving generated diff under prepared key?

[hitsumabushi]

@ganeshrn Thank you for comment.

Just for printing diff.
I think printing diff need (before, after) or prepared keys.

ansible/lib/ansible/plugins/callback/__init__.py

Lines 151 to 219 in 9c5d40f

	def _get_diff(self, difflist):
	if not isinstance(difflist, list):
	difflist = [difflist]
	ret = []
	for diff in difflist:
	try:
	with warnings.catch_warnings():
	warnings.simplefilter('ignore')
	if 'dst_binary' in diff:
	ret.append("diff skipped: destination file appears to be binary\n")
	if 'src_binary' in diff:
	ret.append("diff skipped: source file appears to be binary\n")
	if 'dst_larger' in diff:
	ret.append("diff skipped: destination file size is greater than %d\n" % diff['dst_larger'])
	if 'src_larger' in diff:
	ret.append("diff skipped: source file size is greater than %d\n" % diff['src_larger'])
	if 'before' in diff and 'after' in diff:
	# format complex structures into 'files'
	for x in ['before', 'after']:
	if isinstance(diff[x], MutableMapping):
	diff[x] = json.dumps(diff[x], sort_keys=True, indent=4, separators=(',', ': ')) + '\n'
	if 'before_header' in diff:
	before_header = "before: %s" % diff['before_header']
	else:
	before_header = 'before'
	if 'after_header' in diff:
	after_header = "after: %s" % diff['after_header']
	else:
	after_header = 'after'
	before_lines = to_text(diff['before']).splitlines(True)
	after_lines = to_text(diff['after']).splitlines(True)
	if before_lines and not before_lines[-1].endswith('\n'):
	before_lines[-1] += '\n\\ No newline at end of file\n'
	if after_lines and not after_lines[-1].endswith('\n'):
	after_lines[-1] += '\n\\ No newline at end of file\n'
	differ = difflib.unified_diff(before_lines,
	after_lines,
	fromfile=before_header,
	tofile=after_header,
	fromfiledate='',
	tofiledate='',
	n=C.DIFF_CONTEXT)
	difflines = list(differ)
	if len(difflines) >= 3 and sys.version_info[:2] == (2, 6):
	# difflib in Python 2.6 adds trailing spaces after
	# filenames in the -- before/++ after headers.
	difflines[0] = difflines[0].replace(' \n', '\n')
	difflines[1] = difflines[1].replace(' \n', '\n')
	# it also treats empty files differently
	difflines[2] = difflines[2].replace('-1,0', '-0,0').replace('+1,0', '+0,0')
	has_diff = False
	for line in difflines:
	has_diff = True
	if line.startswith('+'):
	line = stringc(line, C.COLOR_DIFF_ADD)
	elif line.startswith('-'):
	line = stringc(line, C.COLOR_DIFF_REMOVE)
	elif line.startswith('@@'):
	line = stringc(line, C.COLOR_DIFF_LINES)
	ret.append(line)
	if has_diff:
	ret.append('\n')
	if 'prepared' in diff:
	ret.append(to_text(diff['prepared']))
	except UnicodeDecodeError:
	ret.append(">> the files are different, but the diff library cannot compare unicode strings\n\n")
	return u''.join(ret)

Is it wrong?

[ganeshrn]

I get it now, so adding diff as part of prepared key results is rendering diff in a readable format in output logs.
The only concern I have here is this change might break backward compatibility for playbook that depend on diff key

[hitsumabushi]

Ah, that may be the problem.
Do you have any idea to keep backward compatibility?

[felixfontein]

Note that this line was only added recently (https://github.com/ansible/ansible/pull/41846/files) for Ansible 1.7 development branch, i.e. it has not been added to a release.
So your change should be safe.

[felixfontein]

In fact, @ganeshrn, you added it a couple of weeks ago ;)

[ganeshrn]

@felixfontein Good catch. Thanks for pointing out :)
@hitsumabushi diff is added as part of result for most network platforms, somehow is was missed in vyos_config for earlier release. I added diff in vyos_config during the recent cliconf refactor work. Looking at this PR I assumed that it was present since earlier releases.

[ganeshrn]

@hitsumabushi Thank you!