def _query_create_node(self, type, properties):
""" Create, store, and return a new Neo4j node using Gremlin.
Keys: node_id, type, properties, edges
Required:
str type type of neo4j node to create
dict properties properties to set in new neo4j node
Returns:
dict properly formatted node
"""
# add type to properties dictionary before generating script
properties[NODE_PROPERTY.TYPE] = type
# write a gremlin query and specify substitution fields
# TODO: does grabbing the empty edges list take time here?
script = "g.addVertex({0}).transform{{[it, it.outE()]}}".format(
NODE_PROPERTY.PROPERTIES)
# specify substitution values for the gremlin query
parameters = {NODE_PROPERTY.PROPERTIES: properties}
# send a request to the database
response = self._gremlin(script, parameters)
# format the response as a proper node
if response is None:
# TODO: raise DbWriteError
return None
else:
return response_parser.format_node(response[0])
def _query_read_node_and_edges(self, node_id):
""" Read and return a Neo4j node and its edges using Gremlin.
Keys: node_id, type, properties, edges
Required:
id node_id id of node to query
Return:
dict properly formatted node
"""
# write a gremlin query and specify substitution fields
# [ [ { v }, [ { Pipe }, { Pipe }, { Pipe } ] ] ]
script = "g.v({0}).transform{{[it, it.outE()]}}".format(
NODE_PROPERTY.ID)
# specify substitution values for the gremlin query
params = {NODE_PROPERTY.ID: node_id}
# send a request to the database
response = self._gremlin(script, params)
# format response as a proper node
if response is None:
return None
else:
return response_parser.format_node(response[0])