ddbmock -- a DynamoDB mock implementation.

Presentation

DynamoDB is a minimalistic NoSQL engine provided by Amazon as a part of their AWS product.

DynamoDB allows you to store documents composed of unicode, number or binary data as well are sets. Each tables must define a hash_key and may define a range_key. All other fields are optional.

DynamoDB is really awesome but is terribly slooooow with managment tasks. This makes it completly unusable in test environements.

ddbmock brings a nice, tiny, in-memory or sqlite implementation of DynamoDB along with much better and detailed error messages. Among its niceties, it features a double entry point:

> - regular network based entry-point with 1:1 correspondance with > stock DynamoDB > - embeded entry-point with seamless boto intergration 1, ideal > to avoid spinning yet another server.

ddbmock is not intended for production use. It will lose your data. you've been warned! I currently recommend the "boto extension" mode for unit-tests and the "server" mode for functional tests.

Installation

$ pip install ddbmock

Developing

$ hg clone ssh://hg@bitbucket.org/Ludia/dynamodb-mock
$ pip install nose nosexcover coverage mock webtest boto
$ python setup.py develop
$ nosetests # --no-skip to run boto integration tests too

What is ddbmock not useful for ?

Do not use it in production or as a cheap DynamoDB replacement. I'll never stress it enough.

All the focus was on simplicity/hackability and simulation quality. Nothing else.

What is ddbmock useful for ?

• FAST and RELIABLE unit testing
• FAST and RELIABLE functional testing
• experiment with DynamoDB API.
• RELIABLE throughput planification
• RELIABLE disk space planification
• almost any DynamoDB simulation !

ddbmock can also persist your data in SQLITE. This open another vast range of possibilities 😃

Current status

• pass all boto integration tests
• support full table life-cycle
• support full item life-cycle
• support for all item limitations
• accurate size, throughput reporting
• no limits on concurent table operations
• no limits for request/response size nor item count in these

See for detailed up-to-date status.

History

> - v1.0.0 (*): full documentation and bugfixes > - v0.4.1: schema persistence + thread safety, bugfixes > - v0.4.0: sqlite backend + throughput statistics + refactoring, more > documentation, more tests > - v0.3.2: batchWriteItem support + pass boto integration tests > - v0.3.1: accuracy in item/table sizes + full test coverage > - v0.3.0: first public release. Full table lifecycle + most items > operations

(?) indicates a future release. These are only ideas or "nice to have".

Example usage

Run as Regular client-server

Ideal for test environment. For stage and production I highly recommend using DynamoDB servers. ddbmock comes with no warranty and will loose your data(tm).

Launch the server

$ pserve development.ini # launch the server on 0.0.0.0:6543

Start the client

import boto
from ddbmock import connect_boto_network

# Use the provided helper to connect your *own* endpoint
db = connect_boto_network()

# Done ! just use it wherever in your project as usual.
db.list_tables() # get list of tables (empty at this stage)

Note: if you do not want to import ddbmock only for the helper, here is a reference implementation:

def connect_boto_network(host='localhost', port=6543):
    import boto
    from boto.regioninfo import RegionInfo
    endpoint = '{}:{}'.format(host, port)
    region = RegionInfo(name='ddbmock', endpoint=endpoint)
    return boto.connect_dynamodb(region=region, port=port, is_secure=False)

Run as a standalone library

Ideal for unit testing or small scale automated functional tests. Nice to play around with boto DynamoDB API too 😃

import boto
from ddbmock import connect_boto_patch

# Wire-up boto and ddbmock together
db = connect_boto_patch()

# Done ! just use it wherever in your project as usual.
db.list_tables() # get list of tables (empty at this stage)

Note, to clean patches made in boto.dynamodb.layer1, you can call clean_boto_patch() from the same module.

Requirements

> - Python 2.7.x > - Pyramid >= 1.3 > - Boto >= 2.5.0 (optional) > - NO AWS account 😃

Related Links

ddbmock

• Full documentation:
• Report bugs:
• Download:

Dynamodb-mapper

• Full documentation:

• Report bugs:

• Download:

Boto

• Full documentation:

• Report bugs:

• Download: