338 lines
8.1 KiB
Python
338 lines
8.1 KiB
Python
|
from boto.dynamodb2.types import STRING
|
||
|
|
||
|
|
||
|
class BaseSchemaField(object):
|
||
|
"""
|
||
|
An abstract class for defining schema fields.
|
||
|
|
||
|
Contains most of the core functionality for the field. Subclasses must
|
||
|
define an ``attr_type`` to pass to DynamoDB.
|
||
|
"""
|
||
|
attr_type = None
|
||
|
|
||
|
def __init__(self, name, data_type=STRING):
|
||
|
"""
|
||
|
Creates a Python schema field, to represent the data to pass to
|
||
|
DynamoDB.
|
||
|
|
||
|
Requires a ``name`` parameter, which should be a string name of the
|
||
|
field.
|
||
|
|
||
|
Optionally accepts a ``data_type`` parameter, which should be a
|
||
|
constant from ``boto.dynamodb2.types``. (Default: ``STRING``)
|
||
|
"""
|
||
|
self.name = name
|
||
|
self.data_type = data_type
|
||
|
|
||
|
def definition(self):
|
||
|
"""
|
||
|
Returns the attribute definition structure DynamoDB expects.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> field.definition()
|
||
|
{
|
||
|
'AttributeName': 'username',
|
||
|
'AttributeType': 'S',
|
||
|
}
|
||
|
|
||
|
"""
|
||
|
return {
|
||
|
'AttributeName': self.name,
|
||
|
'AttributeType': self.data_type,
|
||
|
}
|
||
|
|
||
|
def schema(self):
|
||
|
"""
|
||
|
Returns the schema structure DynamoDB expects.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> field.schema()
|
||
|
{
|
||
|
'AttributeName': 'username',
|
||
|
'KeyType': 'HASH',
|
||
|
}
|
||
|
|
||
|
"""
|
||
|
return {
|
||
|
'AttributeName': self.name,
|
||
|
'KeyType': self.attr_type,
|
||
|
}
|
||
|
|
||
|
|
||
|
class HashKey(BaseSchemaField):
|
||
|
"""
|
||
|
An field representing a hash key.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> from boto.dynamodb2.types import NUMBER
|
||
|
>>> HashKey('username')
|
||
|
>>> HashKey('date_joined', data_type=NUMBER)
|
||
|
|
||
|
"""
|
||
|
attr_type = 'HASH'
|
||
|
|
||
|
|
||
|
class RangeKey(BaseSchemaField):
|
||
|
"""
|
||
|
An field representing a range key.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> from boto.dynamodb2.types import NUMBER
|
||
|
>>> HashKey('username')
|
||
|
>>> HashKey('date_joined', data_type=NUMBER)
|
||
|
|
||
|
"""
|
||
|
attr_type = 'RANGE'
|
||
|
|
||
|
|
||
|
class BaseIndexField(object):
|
||
|
"""
|
||
|
An abstract class for defining schema indexes.
|
||
|
|
||
|
Contains most of the core functionality for the index. Subclasses must
|
||
|
define a ``projection_type`` to pass to DynamoDB.
|
||
|
"""
|
||
|
def __init__(self, name, parts):
|
||
|
self.name = name
|
||
|
self.parts = parts
|
||
|
|
||
|
def definition(self):
|
||
|
"""
|
||
|
Returns the attribute definition structure DynamoDB expects.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> index.definition()
|
||
|
{
|
||
|
'AttributeName': 'username',
|
||
|
'AttributeType': 'S',
|
||
|
}
|
||
|
|
||
|
"""
|
||
|
definition = []
|
||
|
|
||
|
for part in self.parts:
|
||
|
definition.append({
|
||
|
'AttributeName': part.name,
|
||
|
'AttributeType': part.data_type,
|
||
|
})
|
||
|
|
||
|
return definition
|
||
|
|
||
|
def schema(self):
|
||
|
"""
|
||
|
Returns the schema structure DynamoDB expects.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> index.schema()
|
||
|
{
|
||
|
'IndexName': 'LastNameIndex',
|
||
|
'KeySchema': [
|
||
|
{
|
||
|
'AttributeName': 'username',
|
||
|
'KeyType': 'HASH',
|
||
|
},
|
||
|
],
|
||
|
'Projection': {
|
||
|
'ProjectionType': 'KEYS_ONLY',
|
||
|
}
|
||
|
}
|
||
|
|
||
|
"""
|
||
|
key_schema = []
|
||
|
|
||
|
for part in self.parts:
|
||
|
key_schema.append(part.schema())
|
||
|
|
||
|
return {
|
||
|
'IndexName': self.name,
|
||
|
'KeySchema': key_schema,
|
||
|
'Projection': {
|
||
|
'ProjectionType': self.projection_type,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
|
||
|
class AllIndex(BaseIndexField):
|
||
|
"""
|
||
|
An index signifying all fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> AllIndex('MostRecentlyJoined', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ])
|
||
|
|
||
|
"""
|
||
|
projection_type = 'ALL'
|
||
|
|
||
|
|
||
|
class KeysOnlyIndex(BaseIndexField):
|
||
|
"""
|
||
|
An index signifying only key fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> KeysOnlyIndex('MostRecentlyJoined', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ])
|
||
|
|
||
|
"""
|
||
|
projection_type = 'KEYS_ONLY'
|
||
|
|
||
|
|
||
|
class IncludeIndex(BaseIndexField):
|
||
|
"""
|
||
|
An index signifying only certain fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> IncludeIndex('GenderIndex', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ], includes=['gender'])
|
||
|
|
||
|
"""
|
||
|
projection_type = 'INCLUDE'
|
||
|
|
||
|
def __init__(self, *args, **kwargs):
|
||
|
self.includes_fields = kwargs.pop('includes', [])
|
||
|
super(IncludeIndex, self).__init__(*args, **kwargs)
|
||
|
|
||
|
def schema(self):
|
||
|
schema_data = super(IncludeIndex, self).schema()
|
||
|
schema_data['Projection']['NonKeyAttributes'] = self.includes_fields
|
||
|
return schema_data
|
||
|
|
||
|
|
||
|
class GlobalBaseIndexField(BaseIndexField):
|
||
|
"""
|
||
|
An abstract class for defining global indexes.
|
||
|
|
||
|
Contains most of the core functionality for the index. Subclasses must
|
||
|
define a ``projection_type`` to pass to DynamoDB.
|
||
|
"""
|
||
|
throughput = {
|
||
|
'read': 5,
|
||
|
'write': 5,
|
||
|
}
|
||
|
|
||
|
def __init__(self, *args, **kwargs):
|
||
|
throughput = kwargs.pop('throughput', None)
|
||
|
|
||
|
if throughput is not None:
|
||
|
self.throughput = throughput
|
||
|
|
||
|
super(GlobalBaseIndexField, self).__init__(*args, **kwargs)
|
||
|
|
||
|
def schema(self):
|
||
|
"""
|
||
|
Returns the schema structure DynamoDB expects.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> index.schema()
|
||
|
{
|
||
|
'IndexName': 'LastNameIndex',
|
||
|
'KeySchema': [
|
||
|
{
|
||
|
'AttributeName': 'username',
|
||
|
'KeyType': 'HASH',
|
||
|
},
|
||
|
],
|
||
|
'Projection': {
|
||
|
'ProjectionType': 'KEYS_ONLY',
|
||
|
},
|
||
|
'ProvisionedThroughput': {
|
||
|
'ReadCapacityUnits': 5,
|
||
|
'WriteCapacityUnits': 5
|
||
|
}
|
||
|
}
|
||
|
|
||
|
"""
|
||
|
schema_data = super(GlobalBaseIndexField, self).schema()
|
||
|
schema_data['ProvisionedThroughput'] = {
|
||
|
'ReadCapacityUnits': int(self.throughput['read']),
|
||
|
'WriteCapacityUnits': int(self.throughput['write']),
|
||
|
}
|
||
|
return schema_data
|
||
|
|
||
|
|
||
|
class GlobalAllIndex(GlobalBaseIndexField):
|
||
|
"""
|
||
|
An index signifying all fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> GlobalAllIndex('MostRecentlyJoined', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ],
|
||
|
... throughput={
|
||
|
... 'read': 2,
|
||
|
... 'write': 1,
|
||
|
... })
|
||
|
|
||
|
"""
|
||
|
projection_type = 'ALL'
|
||
|
|
||
|
|
||
|
class GlobalKeysOnlyIndex(GlobalBaseIndexField):
|
||
|
"""
|
||
|
An index signifying only key fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> GlobalKeysOnlyIndex('MostRecentlyJoined', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ],
|
||
|
... throughput={
|
||
|
... 'read': 2,
|
||
|
... 'write': 1,
|
||
|
... })
|
||
|
|
||
|
"""
|
||
|
projection_type = 'KEYS_ONLY'
|
||
|
|
||
|
|
||
|
class GlobalIncludeIndex(GlobalBaseIndexField, IncludeIndex):
|
||
|
"""
|
||
|
An index signifying only certain fields should be in the index.
|
||
|
|
||
|
Example::
|
||
|
|
||
|
>>> GlobalIncludeIndex('GenderIndex', parts=[
|
||
|
... HashKey('username'),
|
||
|
... RangeKey('date_joined')
|
||
|
... ],
|
||
|
... includes=['gender'],
|
||
|
... throughput={
|
||
|
... 'read': 2,
|
||
|
... 'write': 1,
|
||
|
... })
|
||
|
|
||
|
"""
|
||
|
projection_type = 'INCLUDE'
|
||
|
|
||
|
def __init__(self, *args, **kwargs):
|
||
|
throughput = kwargs.pop('throughput', None)
|
||
|
IncludeIndex.__init__(self, *args, **kwargs)
|
||
|
if throughput:
|
||
|
kwargs['throughput'] = throughput
|
||
|
GlobalBaseIndexField.__init__(self, *args, **kwargs)
|
||
|
|
||
|
def schema(self):
|
||
|
# Pick up the includes.
|
||
|
schema_data = IncludeIndex.schema(self)
|
||
|
# Also the throughput.
|
||
|
schema_data.update(GlobalBaseIndexField.schema(self))
|
||
|
return schema_data
|