def get(self, book_id=None):
#if a book id is sent, return the book
if book_id:
#if book not found will cause an error
try:
book = ndb.Key(urlsafe=book_id).get()
#make sure is book and not customer
assert Book.is_book(book)
self.write_json(book.to_json())
except:
#error on not found
self.response.set_status(404)
#return list of all books
else:
#if request parameter not sent, will be empty string
#convert to lowercase so we get case insensitive string comparison
#http://stackoverflow.com/questions/319426/how-do-i-do-a-case-insensitive-string-comparison-in-python
checked_out_parameter = self.request.get('checkedIn').lower()
#just show books that are not checked in
if checked_out_parameter == 'false':
books = Book.query(Book.checkedIn == False).fetch()
#just show books that are checkedIn
elif checked_out_parameter == 'true':
books = Book.query(Book.checkedIn == True).fetch()
#show all books
else:
books = Book.all()
self.write_json(Book.all_to_json(books))
def get(self, customer_id, book_id=None):
#if customer not found will cause an error
#or if key of non-customer object (such as a book) will also cause error
try:
customer = ndb.Key(urlsafe=customer_id).get()
#get a single book
if book_id:
book = ndb.Key(urlsafe=book_id).get()
#check to make sure customer checked out this book
if book.key not in customer.checked_out:
#not found
self.response.set_status(404)
return
response_data = book.to_json()
#get all of customer's checked out books
else:
books = map(lambda book_key: book_key.get(), customer.checked_out)
response_data = Book.all_to_json(books)
except:
#error on customer not found, or book_id was invalid
self.response.set_status(404)
return
self.write_json(response_data)
