Sprinkle raw strings across the code base

tox / pytest is complaining about lots and lots of invalid escape
sequences in our code base. Sprinkle raw strings or backslash escapes
across the code base to fix most occurences of:

  DeprecationWarning: invalid escape sequence

There is still one warning that keeps repeating, though:

  source:264: DeprecationWarning: invalid escape sequence \d

Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Florence Blanc-Renaud <frenaud@redhat.com>

ipaserver/plugins/baseuser.py

@@ -358,8 +358,12 @@ class baseuser(LDAPObject):
         ),
         Str('preferredlanguage?',
             label=_('Preferred Language'),
-            pattern='^(([a-zA-Z]{1,8}(-[a-zA-Z]{1,8})?(;q\=((0(\.[0-9]{0,3})?)|(1(\.0{0,3})?)))?' \
-             + '(\s*,\s*[a-zA-Z]{1,8}(-[a-zA-Z]{1,8})?(;q\=((0(\.[0-9]{0,3})?)|(1(\.0{0,3})?)))?)*)|(\*))$',
+            pattern=(
+                r'^(([a-zA-Z]{1,8}(-[a-zA-Z]{1,8})?'
+                r'(;q\=((0(\.[0-9]{0,3})?)|(1(\.0{0,3})?)))?'
+                r'(\s*,\s*[a-zA-Z]{1,8}(-[a-zA-Z]{1,8})?'
+                r'(;q\=((0(\.[0-9]{0,3})?)|(1(\.0{0,3})?)))?)*)|(\*))$'
+            ),
             pattern_errmsg='must match RFC 2068 - 14.4, e.g., "da, en-gb;q=0.8, en;q=0.7"',
         ),
         Certificate('usercertificate*',

ipaserver/plugins/certprofile.py

@@ -86,7 +86,7 @@ def ca_enabled_check(_api):
         raise errors.NotFound(reason=_('CA is not configured'))
 
 
-profile_id_pattern = re.compile('^[a-zA-Z]\w*$')
+profile_id_pattern = re.compile(r'^[a-zA-Z]\w*$')
 
 
 def validate_profile_id(ugettext, value):
@@ -230,7 +230,7 @@ class certprofile_import(LDAPCreate):
         ),
     )
 
-    PROFILE_ID_PATTERN = re.compile('^profileId=([a-zA-Z]\w*)', re.MULTILINE)
+    PROFILE_ID_PATTERN = re.compile(r'^profileId=([a-zA-Z]\w*)', re.MULTILINE)
 
     def pre_callback(self, ldap, dn, entry, entry_attrs, *keys, **options):
         ca_enabled_check(self.api)

ipaserver/plugins/dogtag.py

@@ -23,7 +23,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-'''
+r'''
 
 ==============================================
 Backend plugin for RA using Dogtag (e.g. CMS)

ipaserver/plugins/migration.py

@@ -469,7 +469,7 @@ def construct_filter(template, oc_list):
     return template % oc_subfilter
 
 def validate_ldapuri(ugettext, ldapuri):
-    m = re.match('^ldaps?://[-\w\.]+(:\d+)?$', ldapuri)
+    m = re.match(r'^ldaps?://[-\w\.]+(:\d+)?$', ldapuri)
     if not m:
         err_msg = _('Invalid LDAP URI.')
         raise errors.ValidationError(name='ldap_uri', error=err_msg)