DynamoDB + Marshmallow == Dynamallow

This package is a work in progress – Feedback / Suggestions / Etc welcomed!

Two awesome things, better together!

Dynamallow is a Python library that provides integration between the Boto v3 DynamoDB API and Marshmallow. Together they provide a simple, ORM inspired, interface to the DynamoDB service with a fully defined, strongly typed schema.

from dynamallow import MarshModel
from marshmallow import fields

class Book(MarshModel):
    class Table:
        name = 'prod-books'
        hash_key = 'isbn'
        read = 25
        write = 5

    class Schema:
        isbn = fields.String(validate=validate_isbn)
        title = fields.String()
        author = fields.String()
        publisher = fields.String()
        year = fields.Number()


# Store new documents directly from dictionaries
Book.put({
    "isbn": "12345678910",
    "title": "Foo",
    "author": "Mr. Bar",
    "publisher": "Publishorama"
})

# Work with the classes as objects
# You can pass attributes from the schema to the constructor
foo = Book(isbn="12345678910", title="Foo", author="Mr. Bar",
           publisher="Publishorama")
foo.save()

# Or assign attributes
foo = Book()
foo.isbn = "12345678910"
foo.title = "Foo"
foo.author = "Mr. Bar"
foo.publisher = "Publishorama"
foo.save()

# In all cases they go through Schema validation, calls to
# .put or .save can result in ValidationError being raised.

# You can then fetch, query and scan your tables.

# Get on the hash key, and/or range key
Book.get(isbn="12345678910")

# Query based on the keys
Book.query(isbn__begins_with="12345")

# Scan based on attributes
Book.scan(author="Mr. Bar")
Book.scan(author__ne="Mr. Bar")

Documentation

Full documentation can be found online at:

http://borgstrom.github.io/dynamallow/

TODO

• Indexes – Currently there is no support for indexes.

• Schema Migrations

• Partial updates on save()