Add homebrew_analytics module for robust disabling

Originally, a raw call to the `git.config` state was used to disable
Homebrew Analytics. However, this is fragile and recently broke with the
Homebrew 1.0.0 release, which migrated the Homebrew repository location.
Now that we have support for custom modules, add a `homebrew` execution
module to allow running arbitrary Homebrew commands, and a
`homebrew_analytics` module on top which allows robustly disabling
Homebrew Analytics by using the builtin `brew analytics` command.

The execution module is named `homebrew` because the built-in module
[`mac_brew.py`] is not available (hidden behind the `pkg`
__virtualname__), so its methods cannot be called.

_modules/homebrew.py

@@ -0,0 +1,89 @@
+# This module is mainly comprised of new code, but also contains modified
+# versions of functions from the salt/modules/mac_brew.py module from Salt
+# develop (at git revision 3e5218daea73f3f24b82a3078764ccb82c2a1ec9).
+# Functions taken/modified from Salt are marked, all others are original.
+#
+# The original copyright and licensing notice for the methods from the
+# mac_brew.py module is reproduced below in the double-# comment block:
+#
+##   Salt - Remote execution system
+##
+##   Copyright 2014-2015 SaltStack Team
+##
+##   Licensed under the Apache License, Version 2.0 (the "License");
+##   you may not use this file except in compliance with the License.
+##   You may obtain a copy of the License at
+##
+##       http://www.apache.org/licenses/LICENSE-2.0
+##
+##   Unless required by applicable law or agreed to in writing, software
+##   distributed under the License is distributed on an "AS IS" BASIS,
+##   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+##   See the License for the specific language governing permissions and
+##   limitations under the License.
+
+'''
+Module for the management of homebrew
+'''
+from __future__ import absolute_import
+
+# Import python libs
+import logging
+import os
+
+# Import salt libs
+from salt.exceptions import CommandExecutionError
+import salt.utils
+
+# Set up logging
+log = logging.getLogger(__name__)
+
+
+def __virtual__():
+    '''
+    Only work if Homebrew is installed
+    '''
+    if salt.utils.which('brew'):
+        return True
+    return (
+        False,
+        'The homebrew execution module could not be loaded: brew not found'
+    )
+
+
+def _homebrew_bin():
+    '''
+    Returns the full path to the homebrew binary in the PATH.
+    Taken from mac_brew.py with modifications.
+    '''
+    homebrew_dir = __salt__['cmd.run'](
+        'brew --prefix',
+        output_loglevel='trace'
+    )
+    return os.path.join(homebrew_dir, 'bin', 'brew')
+
+
+def cmd_all(args):
+    '''
+    Calls brew with the specified arguments and as the correct user.
+    Taken from mac_brew.py with modifications.
+
+    args:
+        Should be a list of arguments to pass to the `brew` binary.
+    '''
+    user = __salt__['file.get_user'](_homebrew_bin())
+    runas = user if user != __opts__['user'] else None
+    ret = __salt__['cmd.run_all'](
+        ['brew'] + args,
+        runas=runas,
+        output_loglevel='trace',
+        python_shell=False,
+        redirect_stderr=False,
+    )
+    if ret['retcode'] != 0:
+        raise CommandExecutionError(
+            'stdout: {stdout}\n'
+            'stderr: {stderr}\n'
+            'retcode: {retcode}\n'.format(**ret)
+        )
+    return ret

_states/homebrew_analytics.py

@@ -0,0 +1,126 @@
+# This module is mainly comprised of new code, but also contains modified
+# versions of functions from the salt/modules/mac_brew.py module from Salt
+# develop (at git revision 3e5218daea73f3f24b82a3078764ccb82c2a1ec9).
+# Functions taken/modified from Salt are marked, all others are original.
+#
+# The original copyright and licensing notice for the methods from the
+# mac_brew.py module is reproduced below in the double-# comment block:
+#
+##   Salt - Remote execution system
+##
+##   Copyright 2014-2015 SaltStack Team
+##
+##   Licensed under the Apache License, Version 2.0 (the "License");
+##   you may not use this file except in compliance with the License.
+##   You may obtain a copy of the License at
+##
+##       http://www.apache.org/licenses/LICENSE-2.0
+##
+##   Unless required by applicable law or agreed to in writing, software
+##   distributed under the License is distributed on an "AS IS" BASIS,
+##   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+##   See the License for the specific language governing permissions and
+##   limitations under the License.
+
+'''
+Module for the management of homebrew
+'''
+from __future__ import absolute_import
+
+# Import python libs
+import logging
+
+# Import salt libs
+from salt.exceptions import CommandExecutionError
+import salt.utils
+
+# Set up logging
+log = logging.getLogger(__name__)
+
+
+def __virtual__():
+    '''
+    Only work if Homebrew is installed
+    '''
+    if salt.utils.which('brew'):
+        return True
+    return (
+        False,
+        'The homebrew_analytics state mod could not be loaded: brew not found'
+    )
+
+
+def _check_analytics_status():
+    out = __salt__['homebrew.cmd_all'](['analytics', 'state'])['stdout']
+    if len(out) < 1:
+        raise CommandExecutionError('Failed to parse brew analytics state')
+    status_line = out.splitlines()[0]
+    if 'enabled' in status_line:
+        return True
+    elif 'disabled' in status_line:
+            return False
+    raise CommandExecutionError('Failed to parse brew analytics state')
+
+
+def managed(name, **kwargs):
+    '''
+    Manage Homebrew analytics state (either enabled or disabled).
+
+    name
+        Either 'enabled' or 'disabled'
+    '''
+    ret = {
+        'name': name,
+        'changes': {},
+        'result': None,
+        'comment': '',
+    }
+
+    # Var must be called 'name' due to design of Salt
+    wanted = None
+    if name == 'enabled':
+        wanted = True
+    elif name == 'disabled':
+        wanted = False
+    else:
+        ret['result'] = False
+        ret['comment'] = '`name` parameter must be `enabled` or `disabled`'
+        return ret
+    wanted_v = name[:-1]  # Verb form
+
+    try:
+        current = _check_analytics_status()
+        if current == wanted:
+            ret['result'] = True
+            ret['comment'] = 'Homebrew analytics are already {}'.format(name)
+            return ret
+
+        if __opts__['test']:
+            ret['comment'] = 'Homebrew analytics need to be {}'.format(name)
+            return ret
+
+        state_arg = 'on' if wanted else 'off'
+        # Exception bubbles, so we can ignore the return value
+        __salt__['homebrew.cmd_all'](['analytics', state_arg])
+
+        new = _check_analytics_status()
+        if new == wanted:
+            ret['changes']['homebrew_analytics'] = {
+                'old': 'enabled' if current else 'disabled',
+                'new': name,
+            }
+            ret['result'] = True
+            ret['comment'] = 'Homebrew analytics was {}'.format(name)
+            return ret
+        else:
+            ret['result'] = False
+            ret['comment'] = 'Failed to {} Homebrew analytics'.format(wanted_v)
+            return ret
+
+    except CommandExecutionError as err:
+        ret['result'] = False
+        ret['comment'] = 'Failed to {} Homebrew analytics: {}'.format(
+            wanted_v,
+            err
+        )
+        return ret

osx/init.sls

@@ -12,14 +12,6 @@
     - mode: 644
     - source: salt://{{ tpldir }}/files/profile
 
-# Disable Homebrew Analytics
-# TODO: wrap this up into a proper state that uses the `brew analytics` command
-# instead of directly changing the git configuration
-# (requires either upstreaming this state + updating Salt,
-# or Salting the Salt master)
-# TODO: also ensure the `homebrew.analyticsuuid` setting is unset
 disable-homebrew-analytics:
-  git.config:
-    - name: 'homebrew.analyticsdisabled'
-    - value: 'true'
-    - repo: /usr/local/Homebrew
+  homebrew_analytics.managed:
+    - name: disabled