from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session, sessionmaker
from sqlalchemy.ext.declarative import declarative_base
import psycopg2
import os

DBHOST = os.environ['DBHOST']
DBNAME = os.environ['DBNAME']
DBUSER = os.environ['DBUSER']
DBPASS = os.environ['DBPASS']
SQLALCHEMY_DATABASE_URI = 'postgresql+psycopg2://%s:%s@%s:5432/%s' % (DBUSER, DBPASS, DBHOST, DBNAME)

engine = create_engine(SQLALCHEMY_DATABASE_URI, convert_unicode=True)
db_session = scoped_session(sessionmaker(autocommit=False,
                                         autoflush=False,
                                         bind=engine))

Base = declarative_base()
Base.query = db_session.query_property()

def init_db():
    # import all modules here that might define models so that
    # they will be registered properly on the metadata.  Otherwise
    # you will have to import them first before calling init_db()
    import server.models as models
    Base.metadata.create_all(bind=engine)

def drop_all():
    Base.metadata.drop_all(engine)