37259b963e
Verified throwing exception when no servers are available, but correctly recovering and hitting the next server when one is. fixing minor pooling tests ensure we get the right exception back when no servers are available working on tests for retry connections working despite failure Removed old connection_manager and replaced with a simple context manager that allows for easy access to clients within the main pool
cqlengine
cqlengine is a Cassandra CQL 3 Object Mapper for Python with an interface similar to the Django orm and mongoengine
Installation
pip install cqlengine
Getting Started
#first, define a model
from cqlengine import columns
from cqlengine.models import Model
class ExampleModel(Model):
read_repair_chance = 0.05 # optional - defaults to 0.1
example_id = columns.UUID(primary_key=True)
example_type = columns.Integer(index=True)
created_at = columns.DateTime()
description = columns.Text(required=False)
#next, setup the connection to your cassandra server(s)...
>>> from cqlengine import connection
>>> connection.setup(['127.0.0.1:9160'])
#...and create your CQL table
>>> from cqlengine.management import create_table
>>> create_table(ExampleModel)
#now we can create some rows:
>>> em1 = ExampleModel.create(example_type=0, description="example1", created_at=datetime.now())
>>> em2 = ExampleModel.create(example_type=0, description="example2", created_at=datetime.now())
>>> em3 = ExampleModel.create(example_type=0, description="example3", created_at=datetime.now())
>>> em4 = ExampleModel.create(example_type=0, description="example4", created_at=datetime.now())
>>> em5 = ExampleModel.create(example_type=1, description="example5", created_at=datetime.now())
>>> em6 = ExampleModel.create(example_type=1, description="example6", created_at=datetime.now())
>>> em7 = ExampleModel.create(example_type=1, description="example7", created_at=datetime.now())
>>> em8 = ExampleModel.create(example_type=1, description="example8", created_at=datetime.now())
# Note: the UUID and DateTime columns will create uuid4 and datetime.now
# values automatically if we don't specify them when creating new rows
#and now we can run some queries against our table
>>> ExampleModel.objects.count()
8
>>> q = ExampleModel.objects(example_type=1)
>>> q.count()
4
>>> for instance in q:
>>> print instance.description
example5
example6
example7
example8
#here we are applying additional filtering to an existing query
#query objects are immutable, so calling filter returns a new
#query object
>>> q2 = q.filter(example_id=em5.example_id)
>>> q2.count()
1
>>> for instance in q2:
>>> print instance.description
example5
Contributing
If you'd like to contribute to cqlengine, please read the contributor guidelines