pokedex/db/__init__.py

   1 # encoding: utf-8
   2 import re
   3
   4 from sqlalchemy import MetaData, Table, engine_from_config, orm
   5
   6 from ..defaults import get_default_db_uri
   7 from .tables import metadata
   8 from .multilang import MultilangSession, MultilangScopedSession
   9
  10
  11 def connect(uri=None, session_args={}, engine_args={}, engine_prefix=''):
  12     """Connects to the requested URI.  Returns a session object.
  13
  14     With the URI omitted, attempts to connect to a default SQLite database
  15     contained within the package directory.
  16
  17     Calling this function also binds the metadata object to the created engine.
  18     """
  19
  20     # If we didn't get a uri, fall back to the default
  21     if uri is None:
  22         uri = engine_args.get(engine_prefix + 'url', None)
  23     if uri is None:
  24         uri = get_default_db_uri()
  25
  26     ### Do some fixery for MySQL
  27     if uri.startswith('mysql:'):
  28         # MySQL uses latin1 for connections by default even if the server is
  29         # otherwise oozing with utf8; charset fixes this
  30         if 'charset' not in uri:
  31             uri += '?charset=utf8'
  32
  33         # Tables should be InnoDB, in the event that we're creating them, and
  34         # use UTF-8 goddammit!
  35         for table in metadata.tables.values():
  36             table.kwargs['mysql_engine'] = 'InnoDB'
  37             table.kwargs['mysql_charset'] = 'utf8'
  38
  39     ### Connect
  40     engine_args[engine_prefix + 'url'] = uri
  41     engine = engine_from_config(engine_args, prefix=engine_prefix)
  42     conn = engine.connect()
  43     metadata.bind = engine
  44
  45     all_session_args = dict(autoflush=True, autocommit=False, bind=engine)
  46     all_session_args.update(session_args)
  47     sm = orm.sessionmaker(class_=MultilangSession, **all_session_args)
  48     session = MultilangScopedSession(sm)
  49
  50     return session
  51
  52 def identifier_from_name(name):
  53     """Make a string safe to use as an identifier.
  54
  55     Valid characters are lowercase alphanumerics and "-". This function may
  56     raise ValueError if it can't come up with a suitable identifier.
  57
  58     This function is useful for scripts which add things with names.
  59     """
  60     if isinstance(name, str):
  61         identifier = name.decode('utf-8')
  62     else:
  63         identifier = name
  64     identifier = identifier.lower()
  65     identifier = identifier.replace(u'+', u' plus ')
  66     identifier = re.sub(u'[ _–]+', u'-', identifier)
  67     identifier = re.sub(u"['./;’(),:]", u'', identifier)
  68     identifier = identifier.replace(u'é', u'e')
  69     identifier = identifier.replace(u'♀', u'-f')
  70     identifier = identifier.replace(u'♂', u'-m')
  71     if identifier in (u'???', u'????'):
  72         identifier = u'unknown'
  73     elif identifier == u'!':
  74         identifier = u'exclamation'
  75     elif identifier == u'?':
  76         identifier = u'question'
  77
  78     if not identifier.replace(u"-", u"").isalnum():
  79         raise ValueError(identifier)
  80     return identifier