def create_list_of_feeds():
dc = DatabaseConnector()
list_of_feeds = dc.get_all_feed_ids() # 4
new_list = []
for i, feedID in enumerate(list_of_feeds):
new_list.append([feedID, dc.get_current_seq_no(feedID)])
return new_list
def filter_events(list_with_needed_extensions):
event_list = []
dc = DatabaseConnector()
for info in list_with_needed_extensions:
appended_events = []
feed_id = info[0]
seq_num = info[1]
num = dc.get_current_seq_no(feed_id)
for i in range(seq_num, num):
extension = dc.get_event(feed_id, i + 1)
appended_events.append(extension)
print("Extension with", len(appended_events), "events")
event_list.append(appended_events)
return event_list
def verify_validation(i_want_list, received_event):
feed_id = i_want_list[0]
seq_num = i_want_list[1]
dc = DatabaseConnector()
last_event = dc.get_event(feed_id, seq_num)
# Controlling if last event exists
if last_event is None:
# If the list has -1, it means it is a new feed to create
if seq_num == -1:
print("Awaiting creation of new feed:", feed_id)
return True
else:
return False
last_event = cbor.loads(last_event)
last_meta = cbor.loads(last_event[0]) # meta
received_event = cbor.loads(received_event)
received_meta = cbor.loads(received_event[0]) # meta
# Controlling feed ids
if last_meta[0] != received_meta[0]:
print("Feed ID validation... FAILED")
return False
print("Feed ID validation... PASSED")
# Controlling sequence numbers
if last_meta[1] + 1 != received_meta[1]:
print("Seq-Num validation... FAILED")
return False
print("Seq-Num validation... PASSED")
# Controlling last meta hash value / prev hash value
if received_meta[2][0] != 0 or get_hash(
last_event[0]) != received_meta[2][1]:
print("Meta Hash validation... FAILED")
return False
print("Meta Hash validation... PASSED")
if last_meta[3] != received_meta[3]:
print("Signature validation... FAILED")
return False
print("Signature validation... PASSED")
print("Extension... VALID")
return True
def compare_feeds(list_of_feeds):
need_list = []
dc = DatabaseConnector()
for i, elem in enumerate(list_of_feeds):
feed_id = elem[0]
seq_num = elem[1]
this_seq_num = dc.get_current_seq_no(feed_id)
# if seq num == -1 that means the feed does not exist in this database
if this_seq_num is None:
print("Entry does not exist...")
need_list.append([feed_id, -1])
elif this_seq_num < seq_num:
elem[1] = this_seq_num
need_list.append(elem)
return need_list
def sync_database(i_want_extensions_list, received_extensions):
received_extensions = cbor.loads(received_extensions)
dc = DatabaseConnector()
if len(i_want_extensions_list) != len(received_extensions):
print(
"Number of received extensions is not as expected. Sync aborted.")
return
print("Number of received extensions:", len(received_extensions))
for i, val in enumerate(i_want_extensions_list):
appended_events_list = received_extensions[i]
# Check if valid
if verify_validation(val, appended_events_list[0]):
for ev in appended_events_list:
dc.add_event(ev)
else:
print(
"The extension is not valid! Sync of one received feed is not possible."
)
print("Finished synchronising!")