pokedex/db/__init__.py

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