class EventProcessor:
def __init__(self, request_id="NONE"):
self.request_id = request_id
# self.api_root = os.environ.get("api_root")
self.events_list = [
"ADD_VOTERS", "ADD_CANDIDATES", "GET_CANDIDATES", "LOCK", "START",
"CAST_VOTE"
]
self.handlers = {
"ADD_VOTERS": self.command_add_voters,
"ADD_CANDIDATES": self.command_add_candidates,
"GET_CANDIDATES": self.command_get_candidates,
"LOCK": self.command_lock,
"START": self.command_start,
"CAST_VOTE": self.command_cast_vote
}
self.db_manager = DynamoDBManager()
self.admin_token = self.db_manager.get_parameter("admin_token")
self.locked = self.db_manager.get_parameter("locked")
self.started = self.db_manager.get_parameter("started")
# EVENT PROCESSING ---------------------------------------------------------
def process_event(self, payload):
event_type = self._determine_event(payload)
if event_type != "UNKNOWN EVENT TYPE":
return self._delegate_event(event_type, payload)
else:
return respond("EVENT VALIDATION FAILED", 400)
def _determine_event(self, payload):
# Determines type of the event, checks validity of the payload according to schema
# At this stage, validity of the token is not checked, we just determine the type of the event
determined_type = "UNKNOWN EVENT TYPE"
for event_type in self.events_list:
try:
result = validate(instance=payload,
schema=schema_dict[event_type + "_SCHEMA"])
determined_type = event_type
except ValidationError as e:
continue
return determined_type
def _delegate_event(self, event_type, payload):
# Delegates the event to the handler
response = self.handlers[event_type](payload)
return response
# COMMAND HANDLERS ---------------------------------------------------------
def command_add_voters(self, payload):
if self.started == "true":
return respond("VOTING ALREADY STARTED", 403)
if payload["administrator_token"] == self.admin_token:
response = VotersManager.add_voters(payload["voters_to_add"])
return response
else:
return respond("WRONG TOKEN, COMMAND REJECTED", 403)
def command_add_candidates(self, payload):
if self.started == "true":
return respond("VOTING ALREADY STARTED", 403)
if payload["administrator_token"] == self.admin_token:
response = CandidatesManager.add_candidates(
payload["candidates_to_add"])
return response
else:
return respond("WRONG TOKEN, COMMAND REJECTED", 403)
def command_get_candidates(self, payload):
# Note that no token is required for this command
if self.started == "false":
return respond("VOTING NOT STARTED YET", 403)
return respond(str(self.db_manager.get_candidates()), 200)
def command_lock(self, payload):
if self.locked == "true":
return respond("SYSTEM ALREADY LOCKED", 403)
if payload["administrator_token"] == self.admin_token:
self.db_manager.set_parameter(parameter="locked", value="true")
return respond("SYSTEM LOCKED", 200)
else:
return respond("WRONG TOKEN, COMMAND REJECTED", 403)
def command_start(self, payload):
if self.locked == "false":
return respond("LOCK THE SYSTEM FIRST", 403)
if self.started == "true":
return respond("VOTING ALREADY STARTED", 403)
if payload["administrator_token"] == self.admin_token:
self.db_manager.set_parameter(parameter="started", value="true")
return respond("VOTING STARTED", 200)
else:
return respond("WRONG TOKEN, COMMAND REJECTED", 403)
def command_cast_vote(self, payload):
if self.started != "true":
return respond("VOTING NOT STARTED YET", 403)
voter = self.db_manager.get_voter(id=payload["voter_id"])
if voter["token"] == payload["voter_token"] and voter[
"voted"] == "false":
response = self.db_manager.add_vote(
voter_id=payload["voter_id"],
event_id=self.request_id,
candidate=payload["candidate_full_name"])
return response
else:
return respond("WRONG TOKEN OR ALREADY VOTED, COMMAND REJECTED",
403)
def test_get_voter(self, mock_boto3_resource):
manager = DynamoDBManager()
id = "some id"
manager.get_voter(id)
manager.voters_table.get_item.assert_called_with(
Key={"student_id": id})