1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
|
# Copyright (c) 2012 Mitch Garnaat http://garnaat.org/
# Copyright (c) 2012 Amazon.com, Inc. or its affiliates. All Rights Reserved
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish, dis-
# tribute, sublicense, and/or sell copies of the Software, and to permit
# persons to whom the Software is furnished to do so, subject to the fol-
# lowing conditions:
#
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
# ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
# SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.
#
from boto.compat import six
class Batch(object):
"""
Used to construct a BatchGet request.
:ivar table: The Table object from which the item is retrieved.
:ivar keys: A list of scalar or tuple values. Each element in the
list represents one Item to retrieve. If the schema for the
table has both a HashKey and a RangeKey, each element in the
list should be a tuple consisting of (hash_key, range_key). If
the schema for the table contains only a HashKey, each element
in the list should be a scalar value of the appropriate type
for the table schema. NOTE: The maximum number of items that
can be retrieved for a single operation is 100. Also, the
number of items retrieved is constrained by a 1 MB size limit.
:ivar attributes_to_get: A list of attribute names.
If supplied, only the specified attribute names will
be returned. Otherwise, all attributes will be returned.
:ivar consistent_read: Specify whether or not to use a
consistent read. Defaults to False.
"""
def __init__(self, table, keys, attributes_to_get=None,
consistent_read=False):
self.table = table
self.keys = keys
self.attributes_to_get = attributes_to_get
self.consistent_read = consistent_read
def to_dict(self):
"""
Convert the Batch object into the format required for Layer1.
"""
batch_dict = {}
key_list = []
for key in self.keys:
if isinstance(key, tuple):
hash_key, range_key = key
else:
hash_key = key
range_key = None
k = self.table.layer2.build_key_from_values(self.table.schema,
hash_key, range_key)
key_list.append(k)
batch_dict['Keys'] = key_list
if self.attributes_to_get:
batch_dict['AttributesToGet'] = self.attributes_to_get
if self.consistent_read:
batch_dict['ConsistentRead'] = True
else:
batch_dict['ConsistentRead'] = False
return batch_dict
class BatchWrite(object):
"""
Used to construct a BatchWrite request. Each BatchWrite object
represents a collection of PutItem and DeleteItem requests for
a single Table.
:ivar table: The Table object from which the item is retrieved.
:ivar puts: A list of :class:`boto.dynamodb.item.Item` objects
that you want to write to DynamoDB.
:ivar deletes: A list of scalar or tuple values. Each element in the
list represents one Item to delete. If the schema for the
table has both a HashKey and a RangeKey, each element in the
list should be a tuple consisting of (hash_key, range_key). If
the schema for the table contains only a HashKey, each element
in the list should be a scalar value of the appropriate type
for the table schema.
"""
def __init__(self, table, puts=None, deletes=None):
self.table = table
self.puts = puts or []
self.deletes = deletes or []
def to_dict(self):
"""
Convert the Batch object into the format required for Layer1.
"""
op_list = []
for item in self.puts:
d = {'Item': self.table.layer2.dynamize_item(item)}
d = {'PutRequest': d}
op_list.append(d)
for key in self.deletes:
if isinstance(key, tuple):
hash_key, range_key = key
else:
hash_key = key
range_key = None
k = self.table.layer2.build_key_from_values(self.table.schema,
hash_key, range_key)
d = {'Key': k}
op_list.append({'DeleteRequest': d})
return (self.table.name, op_list)
class BatchList(list):
"""
A subclass of a list object that contains a collection of
:class:`boto.dynamodb.batch.Batch` objects.
"""
def __init__(self, layer2):
list.__init__(self)
self.unprocessed = None
self.layer2 = layer2
def add_batch(self, table, keys, attributes_to_get=None,
consistent_read=False):
"""
Add a Batch to this BatchList.
:type table: :class:`boto.dynamodb.table.Table`
:param table: The Table object in which the items are contained.
:type keys: list
:param keys: A list of scalar or tuple values. Each element in the
list represents one Item to retrieve. If the schema for the
table has both a HashKey and a RangeKey, each element in the
list should be a tuple consisting of (hash_key, range_key). If
the schema for the table contains only a HashKey, each element
in the list should be a scalar value of the appropriate type
for the table schema. NOTE: The maximum number of items that
can be retrieved for a single operation is 100. Also, the
number of items retrieved is constrained by a 1 MB size limit.
:type attributes_to_get: list
:param attributes_to_get: A list of attribute names.
If supplied, only the specified attribute names will
be returned. Otherwise, all attributes will be returned.
"""
self.append(Batch(table, keys, attributes_to_get, consistent_read))
def resubmit(self):
"""
Resubmit the batch to get the next result set. The request object is
rebuild from scratch meaning that all batch added between ``submit``
and ``resubmit`` will be lost.
Note: This method is experimental and subject to changes in future releases
"""
del self[:]
if not self.unprocessed:
return None
for table_name, table_req in six.iteritems(self.unprocessed):
table_keys = table_req['Keys']
table = self.layer2.get_table(table_name)
keys = []
for key in table_keys:
h = key['HashKeyElement']
r = None
if 'RangeKeyElement' in key:
r = key['RangeKeyElement']
keys.append((h, r))
attributes_to_get = None
if 'AttributesToGet' in table_req:
attributes_to_get = table_req['AttributesToGet']
self.add_batch(table, keys, attributes_to_get=attributes_to_get)
return self.submit()
def submit(self):
res = self.layer2.batch_get_item(self)
if 'UnprocessedKeys' in res:
self.unprocessed = res['UnprocessedKeys']
return res
def to_dict(self):
"""
Convert a BatchList object into format required for Layer1.
"""
d = {}
for batch in self:
b = batch.to_dict()
if b['Keys']:
d[batch.table.name] = b
return d
class BatchWriteList(list):
"""
A subclass of a list object that contains a collection of
:class:`boto.dynamodb.batch.BatchWrite` objects.
"""
def __init__(self, layer2):
list.__init__(self)
self.layer2 = layer2
def add_batch(self, table, puts=None, deletes=None):
"""
Add a BatchWrite to this BatchWriteList.
:type table: :class:`boto.dynamodb.table.Table`
:param table: The Table object in which the items are contained.
:type puts: list of :class:`boto.dynamodb.item.Item` objects
:param puts: A list of items that you want to write to DynamoDB.
:type deletes: A list
:param deletes: A list of scalar or tuple values. Each element
in the list represents one Item to delete. If the schema
for the table has both a HashKey and a RangeKey, each
element in the list should be a tuple consisting of
(hash_key, range_key). If the schema for the table
contains only a HashKey, each element in the list should
be a scalar value of the appropriate type for the table
schema.
"""
self.append(BatchWrite(table, puts, deletes))
def submit(self):
return self.layer2.batch_write_item(self)
def to_dict(self):
"""
Convert a BatchWriteList object into format required for Layer1.
"""
d = {}
for batch in self:
table_name, batch_dict = batch.to_dict()
d[table_name] = batch_dict
return d
|
