Make the charset configurable for mysql

We now have an option to configure the mysql charset used when opening
the database. The default is now utf8 for both, python2 and python3.
No charset argument is passed if this is configured to 'default'.
Previously we were passing 'utf8' for python3 and no charset option for
python2 which made regression tests fail depending on the mysql
configuration.

Author: schlatterbeck

CHANGES.txt

@@ -19,11 +19,6 @@ Fixed:
   Meerwald)
 - exception in logout action when there is no session (Christof
   Meerwald)
-- Supply charset argument for connection creation for mysql, even for
-  python2: The parameter was conditional on python version > 2 but seems to
-  work fine with python2.7. According to the MySQLdb API docs, the
-  charset argument is supported with MySQL 4.1 which was released in
-  2004. (Ralf Schlatterbeck)
 
 Features:
 
@@ -36,6 +31,13 @@ Features:
   Schlatterbeck)
 - Add a 'is_restore_ok' method similar to 'is_retire_ok' for use in
   templates.
+- Allow to configure the mysql charset when opening a connection to the
+  database. The parameter was conditional on python version > 2 but
+  seems to work fine with python2.7. According to the MySQLdb API docs,
+  the charset argument is supported with MySQL 4.1 which was released in
+  2004. There are some legacy reasons why one would want to not pass a
+  charset argument or pass an argument different from the default of
+  'utf8'. (Ralf Schlatterbeck)
 
 2020-04-05 2.0.0 beta 0
 

roundup/backends/back_mysql.py

@@ -54,10 +54,9 @@ def connection_dict(config, dbnamestr=None):
         del d['password']
     if 'port' in d:
         d['port'] = int(d['port'])
-    # This was conditional on python version > 2 but seems to work fine
-    # with python2.7. According to the MySQLdb API docs, the charset
-    # argument is supported with MySQL 4.1 which was released in 2004.
-    d['charset'] = 'utf8'
+    charset = config.RDBMS_MYSQL_CHARSET
+    if charset != 'default':
+        d['charset'] = charset
     return d
 
 def db_nuke(config):

roundup/configuration.py

@@ -1047,6 +1047,12 @@ def str2value(self, value):
         (NullableOption, 'read_default_group', 'roundup',
             "Name of the group to use in the MySQL defaults file (.my.cnf).\n"
             "Only used in MySQL connections."),
+        (Option, 'mysql_charset', 'utf8',
+            "Charset to use for mysql connection,\n"
+            "use 'default' for the mysql default, no charset option\n"
+            "is used when creating the connection in that case.\n"
+            "Otherwise any permissible mysql charset is allowed here.\n"
+            "Only used in MySQL connections."),
         (IntegerNumberGeqZeroOption, 'sqlite_timeout', '30',
             "Number of seconds to wait when the SQLite database is locked\n"
             "Default: use a 30 second timeout (extraordinarily generous)\n"