def new_listing(session, num_of_bedroom, num_of_bathroom, address, zipcode,
listing_price, date_of_listing, agent_id, office_id):
# create house
house = House(num_of_bedroom=num_of_bedroom,
num_of_bathroom=num_of_bathroom,
address=address,
zipcode=zipcode)
session.add(house)
# create listing
listing = Listing(listing_price=listing_price,
date_of_listing=date_of_listing,
status='available',
agent=session.query(Agent).get(agent_id),
office=session.query(Office).get(office_id),
house=house)
session.add(listing)
session.commit()
print ("New listing created with price {:d}".format(listing_price))
def seed_data(session,
num_of_agent=30,
num_of_office=10,
num_of_buyer=300,
num_of_house=500,
num_of_listing=300,
num_of_sale=200):
fake = Faker('en_US')
# create random agent
for i in range(num_of_agent):
agent = Agent(first_name=fake.first_name(),
last_name=fake.last_name(),
phone_number=fake.phone_number(),
email_address=fake.email())
session.add(agent)
session.commit()
# create random offices
# add many to many relationship between offices and agents
for i in range(num_of_office):
agent_ids = random.sample(range(1, num_of_agent + 1),
random.randint(1, min(30, num_of_agent)))
agents = [session.query(Agent).get(id) for id in agent_ids]
office = Office(name=fake.color_name(),
address=fake.street_address(),
agents=agents)
session.add(office)
session.commit()
# create random buyers
for i in range(num_of_buyer):
buyer = Buyer(first_name=fake.first_name(),
last_name=fake.last_name(),
phone_number=fake.phone_number(),
email_address=fake.email())
session.add(buyer)
session.commit()
# create random houses
for i in range(num_of_house):
house = House(num_of_bedroom=random.randint(1, 8),
num_of_bathroom=random.randint(1, 6),
address=fake.street_address(),
zipcode=fake.postalcode())
session.add(house)
session.commit()
# create random listings
# connect agent, office, and house with listing
house_ids = random.sample(range(1, num_of_house + 1), num_of_listing)
for house_id in house_ids:
office = session.query(Office).get(random.randint(1, num_of_office))
agent = random.choice(office.agents)
listing = Listing(listing_price=1000 * random.randint(10, 5000),
date_of_listing=fake.date_between(start_date='-1y',
end_date='today'),
status='available',
agent=agent,
office=office,
house=session.query(House).get(house_id))
session.add(listing)
session.commit()
# create random sales
# connect agent, office, and listing with sale
listing_ids = random.sample(range(1, num_of_listing + 1), num_of_sale)
for listing_id in listing_ids:
listing = session.query(Listing).get(listing_id)
listing.status = 'sold'
# different situations of how the transition between listing and sale happens
# the logic leaky as the next random choice may be the same as the last one
# however this is acceptable as we are only to seed some example data
if random.random(
) < 0.6: # same agent in the same office made the sale
agent = listing.agent
office = listing.office
elif random.random(
) < 0.9: # different agent in the same office made the sale
office = listing.office
agent = random.choice(office.agents)
else: # different agent in a different officen made the sale
office = session.query(Office).get(random.randint(
1, num_of_office))
agent = random.choice(office.agents)
# calculate sale date bese on listing date
listing_datetime = datetime.strptime(listing.date_of_listing,
'%Y-%m-%d')
days_variant = min((datetime.now() - listing_datetime).days, 90)
sale_datetime = listing_datetime + timedelta(
days=random.randint(0, days_variant))
date_of_sale = listing_datetime.strftime('%Y-%m-%d')
# decide sale price base on listing price with probability
if random.random() < 0.6: # sale price is the same as listing price
sale_price = listing.listing_price
else: # sale price is different from listing price
price_variant = int(listing.listing_price / 1000 /
4) # 25% of listing price in thousand dollar
sale_price = listing.listing_price + 1000 * random.randint(
-price_variant, price_variant)
# create sale object to insert
sale = Sale(sale_price=sale_price,
date_of_sale=date_of_sale,
buyer=session.query(Buyer).get(
random.randint(1, num_of_buyer)),
agent=agent,
office=office,
listing=listing)
session.add(sale)
session.commit()
print("Database seeded with random data")
