Fix octal output in a few more places (#17250)

Fix filetree lookup plugin for python3 (octal output and selinux API
takes native strings)

docsite/rst/developing_modules_python3.rst

@@ -131,6 +131,29 @@ modules should create their octals like this::
     # Can't use 0755 on Python-3 and can't use 0o755 on Python-2.4
     EXECUTABLE_PERMS = int('0755', 8)
 
+Outputting octal numbers may also need to be changed.  In python2 we often did
+this to return file permissions::
+
+    mode = int('0775', 8)
+    result['mode'] = oct(mode)
+
+This would give the user ``result['mode'] == '0755'`` in their playbook.  In
+python3, :func:`oct` returns the format with the lowercase ``o`` in it like:
+``result['mode'] == '0o755'``.  If a user had a conditional in their playbook
+or was using the mode in a template the new format might break things.  We
+need to return the old form of mode for backwards compatibility.  You can do
+it like this::
+
+    mode = int('0775', 8)
+    result['mode'] = '0%03o' % mode
+
+You should use this wherever backwards compatibility is a concern or you are
+dealing with file permissions.  (With file permissions a user may be feeding
+the mode into another program or to another module which doesn't understand
+the python syntax for octal numbers.  ``[zero][digit][digit][digit]`` is
+understood by most everything and therefore the right way to express octals in
+these cisrcumstances.
+
 Bundled six
 -----------
 

lib/ansible/module_utils/basic.py

@@ -1013,10 +1013,10 @@ class AnsibleModule(object):
             if diff is not None:
                 if 'before' not in diff:
                     diff['before'] = {}
-                diff['before']['mode'] = oct(prev_mode)
+                diff['before']['mode'] = '0%03o' % prev_mode
                 if 'after' not in diff:
                     diff['after'] = {}
-                diff['after']['mode'] = oct(mode)
+                diff['after']['mode'] = '0%03o' % mode
 
             if self.check_mode:
                 return True

lib/ansible/plugins/lookup/filetree.py

@@ -23,6 +23,8 @@ import grp
 import stat
 
 from ansible.plugins.lookup import LookupBase
+from ansible.utils.unicode import to_str
+
 from __main__ import display
 warning = display.warning
 
@@ -33,25 +35,15 @@ try:
 except ImportError:
     pass
 
-def _to_filesystem_str(path):
-    '''Returns filesystem path as a str, if it wasn't already.
-
-    Used in selinux interactions because it cannot accept unicode
-    instances, and specifying complex args in a playbook leaves
-    you with unicode instances.  This method currently assumes
-    that your filesystem encoding is UTF-8.
-
-    '''
-    if isinstance(path, unicode):
-        path = path.encode("utf-8")
-    return path
 
 # If selinux fails to find a default, return an array of None
 def selinux_context(path):
     context = [None, None, None, None]
     if HAVE_SELINUX and selinux.is_selinux_enabled():
         try:
-            ret = selinux.lgetfilecon_raw(_to_filesystem_str(path))
+            # note: the selinux module uses byte strings on python2 and text
+            # strings on python3
+            ret = selinux.lgetfilecon_raw(to_str(path))
         except OSError:
             return context
         if ret[0] != -1:
@@ -60,6 +52,7 @@ def selinux_context(path):
             context = ret[1].split(':', 3)
     return context
 
+
 def file_props(root, path):
     ''' Returns dictionary with file properties, or return None on failure '''
     abspath = os.path.join(root, path)
@@ -94,7 +87,7 @@ def file_props(root, path):
         ret['group'] = grp.getgrgid(st.st_gid).gr_name
     except KeyError:
         ret['group'] = st.st_gid
-    ret['mode'] = str(oct(stat.S_IMODE(st.st_mode)))
+    ret['mode'] = '0%03o' % (stat.S_IMODE(st.st_mode))
     ret['size'] = st.st_size
     ret['mtime'] = st.st_mtime
     ret['ctime'] = st.st_ctime