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import random
from axiom.item import Item
from axiom.attributes import text, timestamp, reference, integer, AND, OR
from axiom.store import Store
from epsilon import extime
_d = extime.Time.fromISO8601TimeAndDate
_books = [
(u'Heart of Darkness', u'Joseph Conrad', u'0486264645', 80, _d('1990-07-01T00:00:00.000001')),
(u'The Dark Tower, Book 7', u'Stephen King', u'1880418622', 864, _d('2004-11-21T00:00:00.000001')),
(u'Guns, Germs, and Steel: The Fates of Human Societies', u'Jared Diamond', u'0393317552', 480, _d('1999-04-01T00:00:00.000001')),
(u'The Lions of al-Rassan', u'Guy Gavriel Kay', u'0060733497', 528, _d('2005-06-28T00:00:00.000001')),
]
_borrowers = [u'Anne', u'Bob', u'Carol', u'Dave']
class Borrower(Item):
typeName = 'borrower'
schemaVersion = 1
name = text(indexed=True)
class Book(Item):
typeName = 'book'
schemaVersion = 1
title = text()
author = text()
isbn = text()
pages = integer()
datePublished = timestamp()
lentTo = reference()
library = reference()
class LendingLibrary(Item):
typeName = 'lending_library'
schemaVersion = 1
name = text()
def books(self):
return self.store.query(Book,
Book.library == self)
def getBorrower(self, name):
for b in self.store.query(Borrower,
Borrower.name == name):
return b
b = Borrower(name=name,
store=self.store)
return b
def initialize(self):
for title, author, isbn, pages, published in _books:
b = Book(
title=title,
author=author,
isbn=isbn,
pages=pages,
datePublished=published,
library=self,
store=self.store)
def displayBooks(self):
for book in self.books():
print book.title,
if book.lentTo is not None:
print 'lent to', '['+book.lentTo.name+']'
else:
print 'in library'
def shuffleLending(self):
for book in self.books():
if book.lentTo is not None:
print book.lentTo.name, 'returned', book.title
book.lentTo = None
for book in self.books():
if random.choice([True, False]):
borrower = random.choice(_borrowers)
print 'Lending', book.title, 'to', borrower
book.lentTo = self.getBorrower(borrower)
def main(s):
for ll in s.query(LendingLibrary):
print 'found existing library'
break
else:
print 'creating new library'
ll = LendingLibrary(store=s)
ll.initialize()
ll.displayBooks()
print '***'
ll.shuffleLending()
print '---'
ll.displayBooks()
print '***'
ll.shuffleLending()
print '---'
print s.count(Book, AND (Book.author == u'Stephen King',
Book.title == u'The Lions of al-Rassan'))
print s.count(Book, OR (Book.author == u'Stephen King',
Book.title == u'The Lions of al-Rassan'))
if __name__ == '__main__':
s = Store('testdb')
s.transact(main, s)
s.close()
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