urban-meal-delivery/src/urban_meal_delivery/console/gridify.py
Alexander Hess 1bfc7db916
Make Grid.gridify() use only pickup addresses
- ensure a `Restaurant` only has one unique `Order.pickup_address`
- rework `Grid.gridify()` so that only pickup addresses are assigned
  into `Pixel`s
- include database migrations to ensure the data adhere to these
  tighter constraints
2021-01-24 19:04:39 +01:00

48 lines
1.6 KiB
Python

"""CLI script to create pixel grids."""
import click
from urban_meal_delivery import config
from urban_meal_delivery import db
from urban_meal_delivery.console import decorators
@click.command()
@decorators.db_revision('e86290e7305e')
def gridify() -> None: # pragma: no cover note:b1f68d24
"""Create grids for all cities.
This command creates grids with pixels of various
side lengths (specified in `urban_meal_delivery.config`).
Pixels are only generated if they contain at least one
(pickup or delivery) address.
All data are persisted to the database.
"""
cities = db.session.query(db.City).all()
click.echo(f'{len(cities)} cities retrieved from the database')
for city in cities:
click.echo(f'\nCreating grids for {city.name}')
for side_length in config.GRID_SIDE_LENGTHS:
click.echo(f'Creating grid with a side length of {side_length} meters')
grid = db.Grid.gridify(city=city, side_length=side_length)
db.session.add(grid)
click.echo(f' -> created {len(grid.pixels)} pixels')
# The number of assigned addresses is the same across different `side_length`s.
db.session.flush() # necessary for the query to work
n_assigned = (
db.session.query(db.AddressPixelAssociation)
.filter(db.AddressPixelAssociation.grid_id == grid.id)
.count()
)
click.echo(
f'=> assigned {n_assigned} out of {len(city.addresses)} addresses in {city.name}', # noqa:E501
)
db.session.commit()