class DBAccessor:
def __init__(self):
self.db = None
self.image_table = None
self.tree_table = None
self.history_table = None
def connect(self, region=None, aws_access_key_id=None, aws_secret_access_key=None, conn=None):
self.db = DynamoDB()
self.db.connect(region, aws_access_key_id, aws_secret_access_key, conn)
def table_init(self, image_table_name, tree_table_name, history_table_name):
self.image_table = self.db.get_table(image_table_name)
self.tree_table = self.db.get_table(tree_table_name)
self.history_table = self.db.get_table(history_table_name)
def _table_existence_check(self, table):
if not table:
raise ValueError("Table not found: table init is required")
return table
def add_or_update_history(self, name, version, node_attrs):
self._table_existence_check(self.history_table)
item = self.db.get_item(self.history_table, name, range_key=version)
if item:
for attr in node_attrs.keys():
item[attr] = node_attrs[attr]
else:
item = self.db.add_item(self.history_table, name, node_attrs, range_key=version)
self.db.commit(item)
def add_or_update_image(self, name, parent_name, version, sha1, comment, create_date, committer, mail=" ", security_patch=" "):
self._table_existence_check(self.image_table)
content = {'version': version,
'commit_sha1': sha1,
'comment': comment,
'create_date': create_date,
'committer': committer,
'committer_mail': mail,
'security_patch': security_patch,
'parent_name': parent_name}
item = self.db.get_item(self.image_table, name)
if item:
for attr in content.keys():
item[attr] = content[attr]
else:
item = self.db.add_item(self.image_table, name, content)
self.db.commit(item)
self.add_or_update_history(name, version, content)
def _update_children_list(self, item, my_name):
if type(item['children']) is set:
children_list = list(item['children'])
else:
# empty originally - dynamodb doesn't support empty set or string as value
children_list = list()
if my_name not in children_list:
children_list.append(my_name)
item['children'] = set(children_list)
def add_or_update_tree_node(self, my_name, parent_name):
self._table_existence_check(self.tree_table)
item = self.db.get_item(self.tree_table, parent_name)
# update parent list
if item:
self._update_children_list(item, my_name)
else:
# check root
item = self.db.get_item(self.tree_table, "root")
if not item:
item = self.db.add_item(self.tree_table, "root", {'children': set([my_name]),
'parent_name': "root"})
self._update_children_list(item, my_name)
# add my node
my_item = self.db.get_item(self.tree_table, my_name)
if not my_item:
my_item = self.db.add_item(self.tree_table, my_name, {'children': "NoChild",
'parent_name': parent_name})
self.db.commit(my_item)
self.db.commit(item)
def get_tree_children(self, name):
children_list = list()
parent_node = self.db.get_item(self.tree_table, name)
if parent_node:
if type(parent_node['children']) is set:
children_list = list(parent_node['children'])
else:
pass
return children_list
def is_leaf(self, name):
node = self.db.get_item(self.tree_table, name)
is_leaf = True
if type(node['children']) is set:
is_leaf = False
return is_leaf
def get_image_item(self, name):
return self.db.get_item(self.image_table, name)
def exist_image(self, name):
return self.db.get_item(self.image_table, name)
def is_root(self, name):
root = False
item = self.db.get_item(self.image_table, name)
if not item:
root = True
return root
def get_version(self, name):
version = None
item = self.db.get_item(self.image_table, name)
if item:
version = item['version']
return version
def _get_attr_by_item(self, item, attr):
return item[attr] if attr in item.keys() else None
def get_node_history(self, node_name, current_version):
node_history = list()
for version in reversed(range(1, int(current_version) + 1)):
item = self.db.get_item(self.history_table, node_name, str(version).zfill(4))
if item:
node_history.append(item)
return node_history
def get_all_image_name(self):
images = list()
for item in self.image_table.scan():
images.append(item['name'])
return images
def connect(self, region=None, aws_access_key_id=None, aws_secret_access_key=None, conn=None):
self.db = DynamoDB()
self.db.connect(region, aws_access_key_id, aws_secret_access_key, conn)