import time
from sqlalchemy import Column, Integer, Numeric, String
from sqlalchemy.orm import deferred, relationship
from sqlalchemy.sql import func
from gtfsdb import config
from gtfsdb.model.base import Base
from gtfsdb.model.shape import Shape
from gtfsdb.model.pattern_base import PatternBase
import logging
log = logging.getLogger(__name__)
__all__ = ['Pattern']
class Pattern(Base, PatternBase):
datasource = config.DATASOURCE_DERIVED
__tablename__ = 'patterns'
shape_id = Column(String(255), primary_key=True, index=True)
pattern_dist = Column(Numeric(20, 10))
trips = relationship(
'Trip',
primaryjoin='Pattern.shape_id==Trip.shape_id',
foreign_keys='(Pattern.shape_id)',
uselist=True, viewonly=True)
shapes = relationship(
'Shape',
primaryjoin='Pattern.shape_id==Shape.shape_id',
foreign_keys='(Shape.shape_id)',
uselist=True, viewonly=True)
@classmethod
def load(cls, db, **kwargs):
start_time = time.time()
session = db.session
q = session.query(
Shape.shape_id,
func.max(Shape.shape_dist_traveled).label('dist')
)
shapes = q.group_by(Shape.shape_id)
for shape in shapes:
pattern = cls()
pattern.shape_id = shape.shape_id
pattern.pattern_dist = shape.dist
if hasattr(cls, 'geom'):
q = session.query(Shape)
q = q.filter(Shape.shape_id == shape.shape_id)
q = q.order_by(Shape.shape_pt_sequence)
pattern.geom_from_shape(q)
session.add(pattern)
session.commit()
session.close()
processing_time = time.time() - start_time
log.debug('{0}.load ({1:.0f} seconds)'.format(cls.__name__, processing_time))
