updater.py: Modifies the db_type setting method

In order to preserve the config file set up of the layman config
file the set_db_type() function has been modified to not use
configparser as it doesn't preserve comments. Changes have also
been made in case the database file ends with the old extension,
so the backup name will end in ".bak" as opposed to the database's
file type.

1 files changed, 25 insertions, 11 deletions

diff --git a/layman/updater.py b/layman/updater.py
index f727632..9d7b176 100644
--- a/layman/updater.py
+++ b/layman/updater.py
@@ -7,6 +7,7 @@ import argparse
 import os
 import shutil
 import sys
+import re
 
 from layman.api           import LaymanAPI
 from layman.compatibility import fileopen
@@ -122,8 +123,10 @@ class Main(object):
 
         db = DB(self.config)
         installed = self.config['installed']
-        backup_name = installed + '.' + self.config['db_type']
         old_ext = os.path.splitext(installed)[1]
+        backup_name = installed + '.' + self.config['db_type']
+        if old_ext == self.config['db_type']:
+            backup_name = installed + '.bak'
         new_name = installed.replace(old_ext, '.db')
 
         if not os.path.isfile(installed):
@@ -271,17 +274,15 @@ class Main(object):
         repos_conf = ConfigHandler(self.config, overlays)
         repos_conf.write()
 
-    def set_db_type(self, migrate_type, installed):
-        if sys.hexversion >= 0x30200f0:
-            import configparser as ConfigParser
-        else:
-            import ConfigParser
 
-        config = ConfigParser.ConfigParser()
+    def set_db_type(self, migrate_type, installed):
         config_path = self.config['config']\
                       % {'configdir': self.config['configdir']}
+        db_type_found = False
+        installed_found = False
         new_conf = os.path.dirname(config_path) + '/' + '._cfg0000_' +\
                    os.path.basename(config_path)
+        new_lines = []
 
         try:
             shutil.copy(config_path, new_conf)
@@ -300,15 +301,28 @@ class Main(object):
             raise Exception(msg)
 
         try:
-            config.read(new_conf)
+            with fileopen(new_conf, 'r') as laymanconf:
+                lines = laymanconf.readlines()
         except Exception as err:
             msg = '  set_db_type() error; failed to read config at "%(path)s".'\
                   '\n  Error was: "%(err)s"' % {'path': new_conf, 'err': err}
             self.output.error(msg)
             raise err
 
-        config.set('MAIN', 'db_type', migrate_type)
-        config.set('MAIN', 'installed', '%(storage)s/'+installed)
+        for line in lines:
+            if re.search('^#*\s*db_type\s*:', line):
+                db_type_found = True
+                line = 'db_type : ' + migrate_type + '\n'
+            if re.search('^#*\s*installed\s*:', line):
+                installed_found = True
+                line = 'installed : %(storage)s/' + installed + '\n'
+            new_lines.append(line)
+
+        if not db_type_found:
+            new_lines.append('db_type : ' + migrate_type + '\n')
+        if not installed_found:
+            new_lines.append('installed : %(storage)s/' + installed + '\n')
 
         with fileopen(new_conf, 'w') as laymanconf:
-            config.write(laymanconf)
+            for line in new_lines:
+                laymanconf.write(line)