bynamodb 0.1.7
High-Level DynamoDB Interface for Pythonwrapping Low-Level Interface of boto
License: MIT

========
BynamoDB
========

High-Level DynamoDB Interface for Python wrapping Low-Level Interface of boto

Installation
============

From PyPi::

    $ pip install bynamodb

From GitHub::

    $ pip install git+https://github.com/teddychoi/BynamoDB#egg=bynamodb

Patch DynamoDBConnection
========================

Set DynamoDBConnection default host and port.

.. code-block:: python

    from bynamodb.patcher import patch_dynamodb_connection

    patch_dynamodb_connection(host='localhost', port=8000)

Model Definition
================
.. code-block:: python

    import datetime
    from bynamodb.attributes import StringAttribute, StringSetAttribute
    from bynamodb.indexes import GlobalAllIndex
    from bynamodb.model import Model
    
    class Article(Model):
        published_at = StringAttribute(hash_key=True)
        id = StringAttribute(range_key=True)
        title = StringAttribute()
        content = StringAttribute()
        author = StringAttribute()
        write_time = StringAttribute(
            default=lambda: str(datetime.datetime.now()))
        tags = StringSetAttribute(default=set())
        thumbnail = StringAttribute(null=True)
        
        class AuthorIndex(GlobalAllIndex):
            read_throughput = 5
            write_throughput = 5
            hash_key = 'author'
            range_key = 'published_at'

Put Item & Get Item
===================
.. code-block:: python

    Article.put_item(
        published_at='2014-12-09',
        id='1',
        title='This is the title',
        content='This is the content',
        author='Bochul Choi'
    )
    article = Article.get_item(hash_key='2014-12-09', range_key='1')

Get Item from Raw Data
======================

You can get items from raw data retrieved from `boto`'s low level API

.. code-block:: python

    from boto.dynamodb2.layer1 import DynamoDBConnection

    conn = DynamoDBConnection()
    raw_data = conn.get_item(
        'Article',
        {
            'published_at': {'S': '2014-12-09'},
            'id': {'S': '1'}
        }
    )
    article = Article.from_raw_data(raw_data['Item'])

Simple Scan & Query
===================
.. code-block:: python

    # Scan all articles that the title starts with "Title"
    articles = Article.scan(title__startswith='Title')
    # Get the total count of matching items
    count = articles.count()
    # Get the iterator of matching items
    items = iter(articles)

    # Query articles that author is "Bochul Choi"
    articles = Article.query(author__eq='Bochul Choi', index_name='AuthorIndex')
    # The query result also provide the count method and iterator
    count = articles.count()
    items = iter(articles)

Complex lookups in Scan & Query
===============================
.. code-block:: python

    from bynamodb.filterexps import Contains, GT
    
    keyword = 'bynamodb'
    filter_exp = GT('published_at', '2014-12-01') & (
        Contains('title', keyword) | Contains('content', keyword.upper()))
    
    # Scan all articles that match the filter expression
    articles = Article.scan(filter_exp)
    
    # Query articles that match the filter expression and the author condition
    author = 'Bochul Choi'
    articles = Atricle.query(author__eq=author, filter_builder=filter_exp,
                             index_name='AuthorIndex')


Batch Writing & Batch Reading
=============================
.. code-block:: python

    with Article.batch_write() as batch:
        batch.put_item({
            'published_at': '2015-02-23',
            'id': '1',
            'title': 'Article 1',
            'content': 'This is the content',
            'author': 'Bochul Choi'
        })
        batch.put_item({
            'published_at': '2015-02-23',
            'id': '2',
            'title': 'Article 2',
            'content': 'This is the content',
            'author': 'Bochul Choi'
        })

    articles = Article.batch_get(
        ('2015-02-23', '1'),
        ('2015-02-23', '2'),
    )


Changelog
=========
0.1.7
    - Skip decoding non-existent attribute.
0.1.6
    - Fix `ResultSet` to stop fetching items regardless of the limit param.
0.1.5
    - Add support `scan_index_forward` and `limit` pamareter for Query API.
0.1.4
    - Set `ExclusiveStartKey` as the untransformed `LastEvaluatedKey`.
0.1.3
    - `Model.delete` needs to use encoded key.
0.1.2
    - `Model.put_item` returns created item.
0.1.1
    - `NumberAttribute` is only saved as number in db.