Quickstart

First define a model and create the backing table in DynamoDB:

>>> import uuid
>>> from bloop import (
...     BaseModel, Boolean, Column, Engine,
...     GlobalSecondaryIndex, String, UUID)
...
>>> class Account(BaseModel):
...     id = Column(UUID, hash_key=True)
...     name = Column(String)
...     email = Column(String)
...     by_email = GlobalSecondaryIndex(
...         projection='keys',
...         hash_key='email')
...     verified = Column(Boolean, default=False)
...
>>> engine = Engine()
>>> engine.bind(Account)

To create an instance and save it in DynamoDB:

>>> account = Account(
...     id=uuid.uuid4(),
...     name='username',
...     email='foo@bar.com')
...
>>> engine.save(account)

You can load the account by id, or query the GSI by email:

>>> same_account = Account(id=account.id)
>>> engine.load(same_account)
>>> q = engine.query(
...     Account.by_email,
...     key=Account.email == 'foo@bar.com')
...
>>> also_same_account = q.first()

Kick it up a notch with conditional operations:

# Only save if the account doesn't already exist
>>> if_not_exist = Account.id.is_(None)
>>> engine.save(account, condition=if_not_exist)

# Only update the account if the name hasn't changed
>>> account.email = 'new@email.com'
>>> engine.save(account, condition=Account.name == 'username')

# Only delete the account if the email hasn't changed since we last saved
>>> engine.delete(account, condition=Account.email == "new@email.com")

Or load the last state of an object before it was deleted:

>>> engine.delete(account, sync="old")
>>> print(f"last email was {account.email}")