pynamodb 1.4.4

A Pythonic Interface to DynamoDB

A Pythonic interface for Amazon’s DynamoDB that supports Python 2 and 3.

DynamoDB is a great NoSQL service provided by Amazon, but the API is verbose. PynamoDB presents you with a simple, elegant API.

Useful links:

• See the full documentation at http://pynamodb.readthedocs.org/

• Ask questions at Google group

• See release notes at http://pynamodb.readthedocs.org/en/latest/release_notes.html

Installation

From PyPi:

$ pip install pynamodb

From GitHub:

$ pip install git+https://github.com/jlafon/PynamoDB#egg=pynamodb

Basic Usage

Create a model that describes your DynamoDB table.

from pynamodb.models import Model
from pynamodb.attributes import UnicodeAttribute

class UserModel(Model):
    """
    A DynamoDB User
    """
    class Meta:
        table_name = "dynamodb-user"
    email = UnicodeAttribute(null=True)
    first_name = UnicodeAttribute(range_key=True)
    last_name = UnicodeAttribute(hash_key=True)

PynamoDB allows you to create the table if needed (it must exist before you can use it!):

UserModel.create_table(read_capacity_units=1, write_capacity_units=1)

Now, search your table for all users with a last name of ‘Smith’ and whose first name begins with ‘J’:

for user in UserModel.query("Smith", first_name__begins_with="J"):
    print(user.first_name)

Create a new user:

user = UserModel("John", "Denver")
user.save()

Retrieve an existing user:

try:
    user = UserModel.get("John", "Denver")
    print(user)
except UserModel.DoesNotExist:
    print("User does not exist")

Advanced Usage

Want to use indexes? No problem:

from pynamodb.models import Model
from pynamodb.indexes import GlobalSecondaryIndex, AllProjection
from pynamodb.attributes import NumberAttribute, UnicodeAttribute

class ViewIndex(GlobalSecondaryIndex):
    class Meta:
        read_capacity_units = 2
        write_capacity_units = 1
        projection = AllProjection()
    view = NumberAttribute(default=0, hash_key=True)

class TestModel(Model):
    class Meta:
        table_name = "TestModel"
    forum = UnicodeAttribute(hash_key=True)
    thread = UnicodeAttribute(range_key=True)
    view = NumberAttribute(default=0)
    view_index = ViewIndex()

Now query the index for all items with 0 views:

for item in TestModel.view_index.query(0):
    print("Item queried from index: {0}".format(item))

It’s really that simple.

Want to use DynamoDB local? Just add a host name attribute and specify your local server.

from pynamodb.models import Model
from pynamodb.attributes import UnicodeAttribute

class UserModel(Model):
    """
    A DynamoDB User
    """
    class Meta:
        table_name = "dynamodb-user"
        host = "http://localhost:8000"
    email = UnicodeAttribute(null=True)
    first_name = UnicodeAttribute(range_key=True)
    last_name = UnicodeAttribute(hash_key=True)

Want to enable streams on a table? Just add a stream_view_type name attribute and specify the type of data you’d like to stream.

from pynamodb.models import Model
from pynamodb.attributes import UnicodeAttribute
from pynamodb.constants import STREAM_NEW_AND_OLD_IMAGE

class AnimalModel(Model):
    """
    A DynamoDB Animal
    """
    class Meta:
        table_name = "dynamodb-user"
        host = "http://localhost:8000"
        stream_view_type = STREAM_NEW_AND_OLD_IMAGE
    type = UnicodeAttribute(null=True)
    name = UnicodeAttribute(range_key=True)
    id = UnicodeAttribute(hash_key=True)

Want to backup and restore a table? No problem.

# Backup the table
UserModel.dump("usermodel_backup.json")

# Restore the table
UserModel.load("usermodel_backup.json")

Features

• Python 3.3, 3.4, 2.6, and 2.7 support

• An ORM-like interface with query and scan filters

• Compatible with DynamoDB Local

• Supports the entire DynamoDB API

• Full table backup/restore

• Support for Unicode, Binary, JSON, Number, Set, and UTC Datetime attributes

• Support for Global and Local Secondary Indexes

• Provides iterators for working with queries, scans, that are automatically paginated

• Automatic pagination for bulk operations

• Complex queries

• Support for Global and Local Secondary Indexes

• Batch operations with automatic pagination

• Iterators for working with Query and Scan operations