#!/usr/bin/env python3 # Copyright (c) 2014-2018 The Bitcoin Core developers # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. """Test mempool persistence. By default, bitcoind will dump mempool on shutdown and then reload it on startup. This can be overridden with the -persistmempool=0 command line option. Test is as follows: - start node0, node1 and node2. node1 has -persistmempool=0 - create 5 transactions on node2 to its own address. Note that these are not sent to node0 or node1 addresses because we don't want them to be saved in the wallet. - check that node0 and node1 have 5 transactions in their mempools - shutdown all nodes. - startup node0. Verify that it still has 5 transactions in its mempool. Shutdown node0. This tests that by default the mempool is persistent. - startup node1. Verify that its mempool is empty. Shutdown node1. This tests that with -persistmempool=0, the mempool is not dumped to disk when the node is shut down. - Restart node0 with -persistmempool=0. Verify that its mempool is empty. Shutdown node0. This tests that with -persistmempool=0, the mempool is not loaded from disk on start up. - Restart node0 with -persistmempool. Verify that it has 5 transactions in its mempool. This tests that -persistmempool=0 does not overwrite a previously valid mempool stored on disk. - Remove node0 mempool.dat and verify savemempool RPC recreates it and verify that node1 can load it and has 5 transactions in its mempool. - Verify that savemempool throws when the RPC is called if node1 can't write to disk. """ from decimal import Decimal import os import time from test_framework.test_framework import BitcoinTestFramework from test_framework.util import assert_equal, assert_raises_rpc_error, wait_until class MempoolPersistTest(BitcoinTestFramework): def set_test_params(self): self.num_nodes = 3 self.extra_args = [[], ["-persistmempool=0"], []] def skip_test_if_missing_module(self): self.skip_if_no_wallet() def run_test(self): chain_height = self.nodes[0].getblockcount() assert_equal(chain_height, 200) self.log.debug("Mine a single block to get out of IBD") self.nodes[0].generate(1) self.sync_all() self.log.debug("Send 5 transactions from node2 (to its own address)") for i in range(5): last_txid = self.nodes[2].sendtoaddress(self.nodes[2].getnewaddress(), Decimal("10")) node2_balance = self.nodes[2].getbalance() self.sync_all() self.log.debug("Verify that node0 and node1 have 5 transactions in their mempools") assert_equal(len(self.nodes[0].getrawmempool()), 5) assert_equal(len(self.nodes[1].getrawmempool()), 5) self.log.debug("Prioritize a transaction on node0") fees = self.nodes[0].getmempoolentry(txid=last_txid)['fees'] assert_equal(fees['base'], fees['modified']) self.nodes[0].prioritisetransaction(txid=last_txid, fee_delta=1000) fees = self.nodes[0].getmempoolentry(txid=last_txid)['fees'] assert_equal(fees['base'] + Decimal('0.00001000'), fees['modified']) self.log.debug("Stop-start the nodes. Verify that node0 has the transactions in its mempool and node1 does not. Verify that node2 calculates its balance correctly after loading wallet transactions.") self.stop_nodes() # Give this node a head-start, so we can be "extra-sure" that it didn't load anything later # Also don't store the mempool, to keep the datadir clean self.start_node(1, extra_args=["-persistmempool=0"]) self.start_node(0) self.start_node(2) # Give bitcoind a second to reload the mempool wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5, timeout=1) wait_until(lambda: len(self.nodes[2].getrawmempool()) == 5, timeout=1) # The others have loaded their mempool. If node_1 loaded anything, we'd probably notice by now: assert_equal(len(self.nodes[1].getrawmempool()), 0) self.log.debug('Verify prioritization is loaded correctly') fees = self.nodes[0].getmempoolentry(txid=last_txid)['fees'] assert_equal(fees['base'] + Decimal('0.00001000'), fees['modified']) # Verify accounting of mempool transactions after restart is correct self.nodes[2].syncwithvalidationinterfacequeue() # Flush mempool to wallet assert_equal(node2_balance, self.nodes[2].getbalance()) self.log.debug("Stop-start node0 with -persistmempool=0. Verify that it doesn't load its mempool.dat file.") self.stop_nodes() self.start_node(0, extra_args=["-persistmempool=0"]) # Give bitcoind a second to reload the mempool time.sleep(1) assert_equal(len(self.nodes[0].getrawmempool()), 0) self.log.debug("Stop-start node0. Verify that it has the transactions in its mempool.") self.stop_nodes() self.start_node(0) wait_until(lambda: len(self.nodes[0].getrawmempool()) == 5) mempooldat0 = os.path.join(self.nodes[0].datadir, 'regtest', 'mempool.dat') mempooldat1 = os.path.join(self.nodes[1].datadir, 'regtest', 'mempool.dat') self.log.debug("Remove the mempool.dat file. Verify that savemempool to disk via RPC re-creates it") os.remove(mempooldat0) self.nodes[0].savemempool() assert os.path.isfile(mempooldat0) self.log.debug("Stop nodes, make node1 use mempool.dat from node0. Verify it has 5 transactions") os.rename(mempooldat0, mempooldat1) self.stop_nodes() self.start_node(1, extra_args=[]) wait_until(lambda: len(self.nodes[1].getrawmempool()) == 5) self.log.debug("Prevent canuckcoind from writing mempool.dat to disk. Verify that `savemempool` fails") # to test the exception we are creating a tmp folder called mempool.dat.new # which is an implementation detail that could change and break this test mempooldotnew1 = mempooldat1 + '.new' os.mkdir(mempooldotnew1) assert_raises_rpc_error(-1, "Unable to dump mempool to disk", self.nodes[1].savemempool) os.rmdir(mempooldotnew1) if __name__ == '__main__': MempoolPersistTest().main()