class GraphNode:
def __init__(self, node=None):
if node is None:
self.node = Node()
else:
self.node = node
def id(self):
"""
:return: node's unique Id
"""
return self.node._id
def labels(self):
"""
:return: labels set
"""
return self.node.labels
def degree(self):
"""
:return: number of relations
"""
return self.node.degree
def property(self, key):
"""
:param key: property name
:return: property value
"""
return self.node.properties[key]
def properties(self):
"""
:return: node's properties dict
"""
return self.node.properties
def relationships(self):
"""
:return: node's relationships iterator
"""
for rel in self.node.match():
i_rel = GraphRelation(rel)
yield i_rel
def outgoing_relationships(self):
"""
:return: node's outgoing relationships iterator
"""
for rel in self.node.match_outgoing():
i_rel = GraphRelation(rel)
yield i_rel
class User:
"""
Creates a User
User has attributes Name, Version and Last Login
When user is creates, a database node is created in Neo4j
When user is infected, the node is remove and replaced by new node (version update)
"""
# Initializer
def __init__(self):
# Give user a full name. Generated randomly
self.name = unicodedata.normalize('NFKD', names.get_full_name()).encode('ascii','ignore')
# Current base version of the website
self.khanAcademyVersion = 'A'
# keep all students in a set
self.students = set()
# keep all coaches in a set
self.coaches = set()
# Number of loggins, int days ago
self.lastLogin = random.randint(0,50)
######################DATABASE#######################
# Save this user as a node in the graph database
self.databaseNode = Node("UserA", name = self.name, khanAcademyVersion = self.khanAcademyVersion, LastLogin = self.lastLogin)
graph.create(self.databaseNode)
def isCoaching(self, student):
if (student != self and (student not in self.students or self not in student.coaches)):
self.students |= {student}
student.coaches |= {self}
######################DATABASE#######################
graph.create(Relationship(self.databaseNode, "IS_COACHING", student.databaseNode))
def isStudent(self, coach):
if (coach != self and (self not in coach.students or coach not in self.coaches)):
coach.students |= {self}
self.coaches |= {coach}
######################DATABASE#######################
graph.create(Relationship(coach.databaseNode, "IS_COACHING", self.databaseNode))
#Class method for user infection
def infect(self):
# Deploys new version of Khan Academy to this user
self.khanAcademyVersion = 'B'
######################DATABASE#######################
# save all relationships, ingoing and outgoing of this node
incomingRel = self.databaseNode.match_incoming(rel_type="IS_COACHING")
outgoingRel = self.databaseNode.match_outgoing(rel_type="IS_COACHING")
# create a node that is of typer UserN
self.databaseNode = Node("UserB", name = self.name, khanAcademyVersion = self.khanAcademyVersion, LastLogin = self.lastLogin)
graph.create(self.databaseNode)
# Build the same relationships as the UserA node
for r in incomingRel:
startNode = r.start_node
graph.create(Relationship(startNode, "IS_COACHING", self.databaseNode))
for r in outgoingRel:
endNode = r.end_node
graph.create(Relationship(self.databaseNode, "IS_COACHING", endNode))
# Delete the old node
cypher.execute("MATCH (u :UserA {khanAcademyVersion: {khanAcademyVersion}, name: {name}})-[r]-() DELETE r", khanAcademyVersion = 'A', name = self.name)
cypher.execute("MATCH n WHERE (n.khanAcademyVersion = {khanAcademyVersion} AND n.name = {name}) DELETE n", khanAcademyVersion = 'A', name = self.name)
