Source Code for Module web.db

  1  #!/usr/bin/python 
  2   
  3  import sqlalchemy 
  4  from sqlalchemy import create_engine 
  5  from sqlalchemy.orm import sessionmaker, scoped_session 
  6  from sqlalchemy.ext.declarative import declarative_base 
  7   
  8  import config 
  9   
 10  Base = declarative_base() 
 11   
 12   
 13 -def get_tables(model): 
 14      for i in dir(model): 
 15          var = getattr(model, i) 
 16          if type(var) == type(Base) and var.__module__ == model.__name__: 
 17              # subtables, many to many relations 
 18              for i in dir(var): 
 19                  var2 = getattr(var, i) 
 20                  if type(var2) == sqlalchemy.schema.Table: 
 21                      yield var2 
 22              yield var 
 23   
 24   
 25  models = ('main.model', 
 26            'pluginmanager.plugins.model', 
 27            'user.model', 
 28            'clientjob.model',) 
 29   
 30 -def init_model(): 
 31      ''' 
 32      returns the needed Base and metadata for defining new classes. 
 33      New classes should inheritance from Base. 
 34   
 35      >>> Base, metadata = init_model() 
 36      ''' 
 37   
 38      base = declarative_base() 
 39      metadata = base.metadata 
 40   
 41      return base, metadata 
 42   
 43   
 44 -def create_from_model(model, database=config.DB): 
 45      ''' 
 46      Create tables defined in a model. 
 47      ''' 
 48   
 49      metadata = model.metadata 
 50      db = create_engine(database, echo=False) 
 51      for table in get_tables(model): 
 52          if type(table) == sqlalchemy.schema.Table: 
 53              t = table 
 54          else: 
 55              print "creating table %s" % table.__tablename__ 
 56              t = metadata.tables[table.__tablename__] 
 57          t.create(bind=db, checkfirst=True) 
 58   
 59   
 60 -def drop_from_model(model, database=config.DB): 
 61      ''' 
 62      Drop tables defined in a model. 
 63      ''' 
 64   
 65      metadata = model.metadata 
 66      s = connect() 
 67   
 68      for table in get_tables(model): 
 69          if type(table) == sqlalchemy.schema.Table: 
 70              continue 
 71          for i in s.query(table).all(): 
 72              s.delete(i) 
 73   
 74      for table in get_tables(model): 
 75          if type(table) == sqlalchemy.schema.Table: 
 76              t = table 
 77          else: 
 78              print "dropping table %s" % table.__tablename__ 
 79              t = metadata.tables[table.__tablename__] 
 80          t.drop(bind=s.bind, checkfirst=True) 
 81      s.commit() 
 82   
 83   
 84 -def connect(database=config.DB): 
 85      db = create_engine(database, echo=False) 
 86      session = scoped_session(sessionmaker(bind=db)) 
 87      return session 
 88   
 89   
 90 -def create(database=config.DB): 
 91      db = create_engine(database, echo=False) 
 92      for model in models: 
 93          m = __import__(model, fromlist=["true"]) 
 94          m.metadata.create_all(db) 
 95   
 96   
 97  if __name__ == '__main__': 
 98      create() 
 99