moto/moto/dynamodb2/models.py
2016-01-11 11:16:15 -07:00

543 lines
19 KiB
Python

from __future__ import unicode_literals
from collections import defaultdict
import datetime
import json
from moto.compat import OrderedDict
from moto.core import BaseBackend
from moto.core.utils import unix_time
from .comparisons import get_comparison_func
class DynamoJsonEncoder(json.JSONEncoder):
def default(self, obj):
if hasattr(obj, 'to_json'):
return obj.to_json()
def dynamo_json_dump(dynamo_object):
return json.dumps(dynamo_object, cls=DynamoJsonEncoder)
class DynamoType(object):
"""
http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DataModel.html#DataModelDataTypes
"""
def __init__(self, type_as_dict):
self.type = list(type_as_dict)[0]
self.value = list(type_as_dict.values())[0]
def __hash__(self):
return hash((self.type, self.value))
def __eq__(self, other):
return (
self.type == other.type and
self.value == other.value
)
def __lt__(self, other):
return self.value < other.value
def __le__(self, other):
return self.value <= other.value
def __gt__(self, other):
return self.value > other.value
def __ge__(self, other):
return self.value >= other.value
def __repr__(self):
return "DynamoType: {0}".format(self.to_json())
def to_json(self):
return {self.type: self.value}
def compare(self, range_comparison, range_objs):
"""
Compares this type against comparison filters
"""
range_values = [obj.value for obj in range_objs]
comparison_func = get_comparison_func(range_comparison)
return comparison_func(self.value, *range_values)
class Item(object):
def __init__(self, hash_key, hash_key_type, range_key, range_key_type, attrs):
self.hash_key = hash_key
self.hash_key_type = hash_key_type
self.range_key = range_key
self.range_key_type = range_key_type
self.attrs = {}
for key, value in attrs.items():
self.attrs[key] = DynamoType(value)
def __repr__(self):
return "Item: {0}".format(self.to_json())
def to_json(self):
attributes = {}
for attribute_key, attribute in self.attrs.items():
attributes[attribute_key] = {
attribute.type: attribute.value
}
return {
"Attributes": attributes
}
def describe_attrs(self, attributes):
if attributes:
included = {}
for key, value in self.attrs.items():
if key in attributes:
included[key] = value
else:
included = self.attrs
return {
"Item": included
}
def update(self, update_expression):
ACTION_VALUES = ['SET', 'REMOVE']
action = None
for value in update_expression.split():
if value in ACTION_VALUES:
# An action
action = value
continue
else:
# A Real value
value = value.lstrip(":").rstrip(",")
if action == "REMOVE":
self.attrs.pop(value, None)
elif action == 'SET':
key, value = value.split("=:")
# TODO deal with other types
self.attrs[key] = DynamoType({"S": value})
def update_with_attribute_updates(self, attribute_updates):
for attribute_name, update_action in attribute_updates.items():
action = update_action['Action']
if action == 'DELETE' and not 'Value' in update_action:
if attribute_name in self.attrs:
del self.attrs[attribute_name]
continue
new_value = list(update_action['Value'].values())[0]
if action == 'PUT':
# TODO deal with other types
if isinstance(new_value, list) or isinstance(new_value, set):
self.attrs[attribute_name] = DynamoType({"SS": new_value})
elif isinstance(new_value, dict):
self.attrs[attribute_name] = DynamoType({"M": new_value})
elif update_action['Value'].keys() == ['N']:
self.attrs[attribute_name] = DynamoType({"N": new_value})
elif update_action['Value'].keys() == ['NULL']:
if attribute_name in self.attrs:
del self.attrs[attribute_name]
else:
self.attrs[attribute_name] = DynamoType({"S": new_value})
class Table(object):
def __init__(self, table_name, schema=None, attr=None, throughput=None, indexes=None, global_indexes=None):
self.name = table_name
self.attr = attr
self.schema = schema
self.range_key_attr = None
self.hash_key_attr = None
self.range_key_type = None
self.hash_key_type = None
for elem in schema:
if elem["KeyType"] == "HASH":
self.hash_key_attr = elem["AttributeName"]
self.hash_key_type = elem["KeyType"]
else:
self.range_key_attr = elem["AttributeName"]
self.range_key_type = elem["KeyType"]
if throughput is None:
self.throughput = {'WriteCapacityUnits': 10, 'ReadCapacityUnits': 10}
else:
self.throughput = throughput
self.throughput["NumberOfDecreasesToday"] = 0
self.indexes = indexes
self.global_indexes = global_indexes if global_indexes else []
self.created_at = datetime.datetime.now()
self.items = defaultdict(dict)
@property
def describe(self):
results = {
'Table': {
'AttributeDefinitions': self.attr,
'ProvisionedThroughput': self.throughput,
'TableSizeBytes': 0,
'TableName': self.name,
'TableStatus': 'ACTIVE',
'KeySchema': self.schema,
'ItemCount': len(self),
'CreationDateTime': unix_time(self.created_at),
'GlobalSecondaryIndexes': [index for index in self.global_indexes],
}
}
return results
def __len__(self):
count = 0
for key, value in self.items.items():
if self.has_range_key:
count += len(value)
else:
count += 1
return count
@property
def hash_key_names(self):
keys = [self.hash_key_attr]
for index in self.global_indexes:
for key in index['KeySchema']:
if key['KeyType'] == 'HASH':
keys.append(key['AttributeName'])
return keys
@property
def range_key_names(self):
keys = [self.range_key_attr]
for index in self.global_indexes:
for key in index['KeySchema']:
if key['KeyType'] == 'RANGE':
keys.append(key['AttributeName'])
return keys
def put_item(self, item_attrs, expected=None, overwrite=False):
hash_value = DynamoType(item_attrs.get(self.hash_key_attr))
if self.has_range_key:
range_value = DynamoType(item_attrs.get(self.range_key_attr))
else:
range_value = None
item = Item(hash_value, self.hash_key_type, range_value, self.range_key_type, item_attrs)
if not overwrite:
if expected is None:
expected = {}
lookup_range_value = range_value
else:
expected_range_value = expected.get(self.range_key_attr, {}).get("Value")
if(expected_range_value is None):
lookup_range_value = range_value
else:
lookup_range_value = DynamoType(expected_range_value)
current = self.get_item(hash_value, lookup_range_value)
if current is None:
current_attr = {}
elif hasattr(current, 'attrs'):
current_attr = current.attrs
else:
current_attr = current
for key, val in expected.items():
if 'Exists' in val and val['Exists'] is False:
if key in current_attr:
raise ValueError("The conditional request failed")
elif key not in current_attr:
raise ValueError("The conditional request failed")
elif DynamoType(val['Value']).value != current_attr[key].value:
raise ValueError("The conditional request failed")
if range_value:
self.items[hash_value][range_value] = item
else:
self.items[hash_value] = item
return item
def __nonzero__(self):
return True
def __bool__(self):
return self.__nonzero__()
@property
def has_range_key(self):
return self.range_key_attr is not None
def get_item(self, hash_key, range_key=None):
if self.has_range_key and not range_key:
raise ValueError("Table has a range key, but no range key was passed into get_item")
try:
if range_key:
return self.items[hash_key][range_key]
else:
return self.items[hash_key]
except KeyError:
return None
def delete_item(self, hash_key, range_key):
try:
if range_key:
return self.items[hash_key].pop(range_key)
else:
return self.items.pop(hash_key)
except KeyError:
return None
def query(self, hash_key, range_comparison, range_objs, index_name=None):
results = []
last_page = True # Once pagination is implemented, change this
if index_name:
all_indexes = (self.global_indexes or []) + (self.indexes or [])
indexes_by_name = dict((i['IndexName'], i) for i in all_indexes)
if index_name not in indexes_by_name:
raise ValueError('Invalid index: %s for table: %s. Available indexes are: %s' % (
index_name, self.name, ', '.join(indexes_by_name.keys())
))
index = indexes_by_name[index_name]
try:
index_hash_key = [key for key in index['KeySchema'] if key['KeyType'] == 'HASH'][0]
except IndexError:
raise ValueError('Missing Hash Key. KeySchema: %s' % index['KeySchema'])
possible_results = []
for item in self.all_items():
if not isinstance(item, Item):
continue
item_hash_key = item.attrs.get(index_hash_key['AttributeName'])
if item_hash_key and item_hash_key == hash_key:
possible_results.append(item)
else:
possible_results = [item for item in list(self.all_items()) if isinstance(item, Item) and item.hash_key == hash_key]
if index_name:
try:
index_range_key = [key for key in index['KeySchema'] if key['KeyType'] == 'RANGE'][0]
except IndexError:
index_range_key = None
if range_comparison:
if index_name and not index_range_key:
raise ValueError('Range Key comparison but no range key found for index: %s' % index_name)
elif index_name:
for result in possible_results:
if result.attrs.get(index_range_key['AttributeName']).compare(range_comparison, range_objs):
results.append(result)
else:
for result in possible_results:
if result.range_key.compare(range_comparison, range_objs):
results.append(result)
else:
# If we're not filtering on range key, return all values
results = possible_results
if index_name:
if index_range_key:
results.sort(key=lambda item: item.attrs[index_range_key['AttributeName']].value
if item.attrs.get(index_range_key['AttributeName']) else None)
else:
results.sort(key=lambda item: item.range_key)
return results, last_page
def all_items(self):
for hash_set in self.items.values():
if self.range_key_attr:
for item in hash_set.values():
yield item
else:
yield hash_set
def scan(self, filters):
results = []
scanned_count = 0
last_page = True # Once pagination is implemented, change this
for result in self.all_items():
scanned_count += 1
passes_all_conditions = True
for attribute_name, (comparison_operator, comparison_objs) in filters.items():
attribute = result.attrs.get(attribute_name)
if attribute:
# Attribute found
if not attribute.compare(comparison_operator, comparison_objs):
passes_all_conditions = False
break
elif comparison_operator == 'NULL':
# Comparison is NULL and we don't have the attribute
continue
else:
# No attribute found and comparison is no NULL. This item fails
passes_all_conditions = False
break
if passes_all_conditions:
results.append(result)
return results, scanned_count, last_page
def lookup(self, *args, **kwargs):
if not self.schema:
self.describe()
for x, arg in enumerate(args):
kwargs[self.schema[x].name] = arg
ret = self.get_item(**kwargs)
if not ret.keys():
return None
return ret
class DynamoDBBackend(BaseBackend):
def __init__(self):
self.tables = OrderedDict()
def create_table(self, name, **params):
if name in self.tables:
return None
table = Table(name, **params)
self.tables[name] = table
return table
def delete_table(self, name):
return self.tables.pop(name, None)
def update_table_throughput(self, name, throughput):
table = self.tables[name]
table.throughput = throughput
return table
def update_table_global_indexes(self, name, global_index_updates):
table = self.tables[name]
gsis_by_name = dict((i['IndexName'], i) for i in table.global_indexes)
for gsi_update in global_index_updates:
gsi_to_create = gsi_update.get('Create')
gsi_to_update = gsi_update.get('Update')
gsi_to_delete = gsi_update.get('Delete')
if gsi_to_delete:
index_name = gsi_to_delete['IndexName']
if index_name not in gsis_by_name:
raise ValueError('Global Secondary Index does not exist, but tried to delete: %s' %
gsi_to_delete['IndexName'])
del gsis_by_name[index_name]
if gsi_to_update:
index_name = gsi_to_update['IndexName']
if index_name not in gsis_by_name:
raise ValueError('Global Secondary Index does not exist, but tried to update: %s' %
gsi_to_update['IndexName'])
gsis_by_name[index_name].update(gsi_to_update)
if gsi_to_create:
if gsi_to_create['IndexName'] in gsis_by_name:
raise ValueError('Global Secondary Index already exists: %s' % gsi_to_create['IndexName'])
gsis_by_name[gsi_to_create['IndexName']] = gsi_to_create
table.global_indexes = gsis_by_name.values()
return table
def put_item(self, table_name, item_attrs, expected=None, overwrite=False):
table = self.tables.get(table_name)
if not table:
return None
return table.put_item(item_attrs, expected, overwrite)
def get_table_keys_name(self, table_name, keys):
"""
Given a set of keys, extracts the key and range key
"""
table = self.tables.get(table_name)
if not table:
return None, None
else:
hash_key = range_key = None
for key in keys:
if key in table.hash_key_names:
hash_key = key
elif key in table.range_key_names:
range_key = key
return hash_key, range_key
def get_keys_value(self, table, keys):
if table.hash_key_attr not in keys or (table.has_range_key and table.range_key_attr not in keys):
raise ValueError("Table has a range key, but no range key was passed into get_item")
hash_key = DynamoType(keys[table.hash_key_attr])
range_key = DynamoType(keys[table.range_key_attr]) if table.has_range_key else None
return hash_key, range_key
def get_table(self, table_name):
return self.tables.get(table_name)
def get_item(self, table_name, keys):
table = self.get_table(table_name)
if not table:
raise ValueError("No table found")
hash_key, range_key = self.get_keys_value(table, keys)
return table.get_item(hash_key, range_key)
def query(self, table_name, hash_key_dict, range_comparison, range_value_dicts, index_name=None):
table = self.tables.get(table_name)
if not table:
return None, None
hash_key = DynamoType(hash_key_dict)
range_values = [DynamoType(range_value) for range_value in range_value_dicts]
return table.query(hash_key, range_comparison, range_values, index_name)
def scan(self, table_name, filters):
table = self.tables.get(table_name)
if not table:
return None, None, None
scan_filters = {}
for key, (comparison_operator, comparison_values) in filters.items():
dynamo_types = [DynamoType(value) for value in comparison_values]
scan_filters[key] = (comparison_operator, dynamo_types)
return table.scan(scan_filters)
def update_item(self, table_name, key, update_expression, attribute_updates):
table = self.get_table(table_name)
if all([table.hash_key_attr in key, table.range_key_attr in key]):
# Covers cases where table has hash and range keys, ``key`` param will be a dict
hash_value = DynamoType(key[table.hash_key_attr])
range_value = DynamoType(key[table.range_key_attr])
elif table.hash_key_attr in key:
# Covers tables that have a range key where ``key`` param is a dict
hash_value = DynamoType(key[table.hash_key_attr])
range_value = None
else:
# Covers other cases
hash_value = DynamoType(key)
range_value = None
item = table.get_item(hash_value, range_value)
if update_expression:
item.update(update_expression)
else:
item.update_with_attribute_updates(attribute_updates)
return item
def delete_item(self, table_name, keys):
table = self.tables.get(table_name)
if not table:
return None
hash_key, range_key = self.get_keys_value(table, keys)
return table.delete_item(hash_key, range_key)
dynamodb_backend2 = DynamoDBBackend()