import collections from threading import RLock import time from helper_sql import * from singleton import Singleton inventoryLock = RLock() # Guarantees that two receiveDataThreads don't receive and process the same message concurrently (probably sent by a malicious individual) InventoryItem = collections.namedtuple('InventoryItem', 'type stream payload expires tag') @Singleton class Inventory(collections.MutableMapping): def __init__(self): super(self.__class__, self).__init__() self._inventory = {} #of objects (like msg payloads and pubkey payloads) Does not include protocol headers (the first 24 bytes of each packet). self.numberOfInventoryLookupsPerformed = 0 self._streams = collections.defaultdict(set) # key = streamNumer, value = a set which holds the inventory object hashes that we are aware of. This is used whenever we receive an inv message from a peer to check to see what items are new to us. We don't delete things out of it; instead, the singleCleaner thread clears and refills it every couple hours. def __contains__(self, hash): with inventoryLock: self.numberOfInventoryLookupsPerformed += 1 if hash in self._inventory: return True return bool(sqlQuery('SELECT 1 FROM inventory WHERE hash=?', hash)) def __getitem__(self, hash): with inventoryLock: if hash in self._inventory: return self._inventory[hash] rows = sqlQuery('SELECT objecttype, streamnumber, payload, expirestime, tag FROM inventory WHERE hash=?', hash) if not rows: raise KeyError(hash) return InventoryItem(*rows[0]) def __setitem__(self, hash, value): with inventoryLock: value = InventoryItem(*value) self._inventory[hash] = value self._streams[value.stream].add(hash) def __delitem__(self, hash): raise NotImplementedError def __iter__(self): with inventoryLock: hashes = self._inventory.keys()[:] hashes += (hash for hash, in sqlQuery('SELECT hash FROM inventory')) return hashes.__iter__() def __len__(self): with inventoryLock: return len(self._inventory) + sqlQuery('SELECT count(*) FROM inventory')[0][0] def by_type_and_tag(self, type, tag): with inventoryLock: values = [value for value in self._inventory.values() if value.type == type and value.tag == tag] values += (InventoryItem(*value) for value in sqlQuery('SELECT objecttype, streamnumber, payload, expirestime, tag FROM inventory WHERE objecttype=? AND tag=?', type, tag)) return values def hashes_by_stream(self, stream): with inventoryLock: return self._streams[stream] def unexpired_hashes_by_stream(self, stream): with inventoryLock: t = int(time.time()) hashes = [hash for hash, value in self._inventory.items() if value.stream == stream and value.expires > t] hashes += (payload for payload, in sqlQuery('SELECT hash FROM inventory WHERE streamnumber=? AND expirestime>?', stream, t)) return hashes def flush(self): with inventoryLock: # If you use both the inventoryLock and the sqlLock, always use the inventoryLock OUTSIDE of the sqlLock. with SqlBulkExecute() as sql: for hash, value in self._inventory.items(): sql.execute('INSERT INTO inventory VALUES (?, ?, ?, ?, ?, ?)', hash, *value) self._inventory.clear() def clean(self): with inventoryLock: sqlExecute('DELETE FROM inventory WHERE expirestime