text: #!/usr/bin/env python3
  # Copyright (c) 2014-2019 The Bitnamicoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  """Base class for RPC testing."""
  
  import configparser
  from enum import Enum
  import argparse
  import logging
  import os
  import pdb
  import random
  import re
  import shutil
  import subprocess
  import sys
  import tempfile
  import time
  
  from .authproxy import JSONRPCException
  from . import coverage
  from .p2p import NetworkThread
  from .test_node import TestNode
  from .util import (
      MAX_NODES,
      PortSeed,
      assert_equal,
      check_json_precision,
      connect_nodes,
      disconnect_nodes,
      get_datadir_path,
      initialize_datadir,
      wait_until_helper,
  )
  
  
  class TestStatus(Enum):
      PASSED = 1
      FAILED = 2
      SKIPPED = 3
  
  TEST_EXIT_PASSED = 0
  TEST_EXIT_FAILED = 1
  TEST_EXIT_SKIPPED = 77
  
  TMPDIR_PREFIX = "bitnamicoin_func_test_"
  
  
  class SkipTest(Exception):
      """This exception is raised to skip a test"""
  
      def __init__(self, message):
          self.message = message
  
  
  class BitnamicoinTestMetaClass(type):
      """Metaclass for BitnamicoinTestFramework.
  
      Ensures that any attempt to register a subclass of `BitnamicoinTestFramework`
      adheres to a standard whereby the subclass overrides `set_test_params` and
      `run_test` but DOES NOT override either `__init__` or `main`. If any of
      those standards are violated, a ``TypeError`` is raised."""
  
      def __new__(cls, clsname, bases, dct):
          if not clsname == 'BitnamicoinTestFramework':
              if not ('run_test' in dct and 'set_test_params' in dct):
                  raise TypeError("BitnamicoinTestFramework subclasses must override "
                                  "'run_test' and 'set_test_params'")
              if '__init__' in dct or 'main' in dct:
                  raise TypeError("BitnamicoinTestFramework subclasses may not override "
                                  "'__init__' or 'main'")
  
          return super().__new__(cls, clsname, bases, dct)
  
  
  class BitnamicoinTestFramework(metaclass=BitnamicoinTestMetaClass):
      """Base class for a bitnamicoin test script.
  
      Individual bitnamicoin test scripts should subclass this class and override the set_test_params() and run_test() methods.
  
      Individual tests can also override the following methods to customize the test setup:
  
      - add_options()
      - setup_chain()
      - setup_network()
      - setup_nodes()
  
      The __init__() and main() methods should not be overridden.
  
      This class also contains various public and private helper methods."""
  
      chain = None  # type: str
      setup_clean_chain = None  # type: bool
  
      def __init__(self):
          """Sets test framework defaults. Do not override this method. Instead, override the set_test_params() method"""
          self.chain = 'regtest'
          self.setup_clean_chain = False
          self.nodes = []
          self.network_thread = None
          self.rpc_timeout = 60  # Wait for up to 60 seconds for the RPC server to respond
          self.supports_cli = True
          self.bind_to_localhost_only = True
          self.set_test_params()
          self.parse_args()
          if self.options.timeout_factor == 0 :
              self.options.timeout_factor = 99999
          self.rpc_timeout = int(self.rpc_timeout * self.options.timeout_factor) # optionally, increase timeout by a factor
  
      def main(self):
          """Main function. This should not be overridden by the subclass test scripts."""
  
          assert hasattr(self, "num_nodes"), "Test must set self.num_nodes in set_test_params()"
  
          try:
              self.setup()
              self.run_test()
          except JSONRPCException:
              self.log.exception("JSONRPC error")
              self.success = TestStatus.FAILED
          except SkipTest as e:
              self.log.warning("Test Skipped: %s" % e.message)
              self.success = TestStatus.SKIPPED
          except AssertionError:
              self.log.exception("Assertion failed")
              self.success = TestStatus.FAILED
          except KeyError:
              self.log.exception("Key error")
              self.success = TestStatus.FAILED
          except subprocess.CalledProcessError as e:
              self.log.exception("Called Process failed with '{}'".format(e.output))
              self.success = TestStatus.FAILED
          except Exception:
              self.log.exception("Unexpected exception caught during testing")
              self.success = TestStatus.FAILED
          except KeyboardInterrupt:
              self.log.warning("Exiting after keyboard interrupt")
              self.success = TestStatus.FAILED
          finally:
              exit_code = self.shutdown()
              sys.exit(exit_code)
  
      def parse_args(self):
          previous_releases_path = os.getenv("PREVIOUS_RELEASES_DIR") or os.getcwd() + "/releases"
          parser = argparse.ArgumentParser(usage="%(prog)s [options]")
          parser.add_argument("--nocleanup", dest="nocleanup", default=False, action="store_true",
                              help="Leave bitnamicoinds and test.* datadir on exit or error")
          parser.add_argument("--noshutdown", dest="noshutdown", default=False, action="store_true",
                              help="Don't stop bitnamicoinds after the test execution")
          parser.add_argument("--cachedir", dest="cachedir", default=os.path.abspath(os.path.dirname(os.path.realpath(__file__)) + "/../../cache"),
                              help="Directory for caching pregenerated datadirs (default: %(default)s)")
          parser.add_argument("--tmpdir", dest="tmpdir", help="Root directory for datadirs")
          parser.add_argument("-l", "--loglevel", dest="loglevel", default="INFO",
                              help="log events at this level and higher to the console. Can be set to DEBUG, INFO, WARNING, ERROR or CRITICAL. Passing --loglevel DEBUG will output all logs to console. Note that logs at all levels are always written to the test_framework.log file in the temporary test directory.")
          parser.add_argument("--tracerpc", dest="trace_rpc", default=False, action="store_true",
                              help="Print out all RPC calls as they are made")
          parser.add_argument("--portseed", dest="port_seed", default=os.getpid(), type=int,
                              help="The seed to use for assigning port numbers (default: current process id)")
          parser.add_argument("--previous-releases", dest="prev_releases", action="store_true",
                              default=os.path.isdir(previous_releases_path) and bool(os.listdir(previous_releases_path)),
                              help="Force test of previous releases (default: %(default)s)")
          parser.add_argument("--coveragedir", dest="coveragedir",
                              help="Write tested RPC commands into this directory")
          parser.add_argument("--configfile", dest="configfile",
                              default=os.path.abspath(os.path.dirname(os.path.realpath(__file__)) + "/../../config.ini"),
                              help="Location of the test framework config file (default: %(default)s)")
          parser.add_argument("--pdbonfailure", dest="pdbonfailure", default=False, action="store_true",
                              help="Attach a python debugger if test fails")
          parser.add_argument("--usecli", dest="usecli", default=False, action="store_true",
                              help="use bitnamicoin-cli instead of RPC for all commands")
          parser.add_argument("--perf", dest="perf", default=False, action="store_true",
                              help="profile running nodes with perf for the duration of the test")
          parser.add_argument("--valgrind", dest="valgrind", default=False, action="store_true",
                              help="run nodes under the valgrind memory error detector: expect at least a ~10x slowdown, valgrind 3.14 or later required")
          parser.add_argument("--randomseed", type=int,
                              help="set a random seed for deterministically reproducing a previous test run")
          parser.add_argument("--descriptors", default=False, action="store_true",
                              help="Run test using a descriptor wallet")
          parser.add_argument('--timeout-factor', dest="timeout_factor", type=float, default=1.0, help='adjust test timeouts by a factor. Setting it to 0 disables all timeouts')
          self.add_options(parser)
          self.options = parser.parse_args()
          self.options.previous_releases_path = previous_releases_path
  
      def setup(self):
          """Call this method to start up the test framework object with options set."""
  
          PortSeed.n = self.options.port_seed
  
          check_json_precision()
  
          self.options.cachedir = os.path.abspath(self.options.cachedir)
  
          config = configparser.ConfigParser()
          config.read_file(open(self.options.configfile))
          self.config = config
          fname_bitnamicoind = os.path.join(
              config["environment"]["BUILDDIR"],
              "src",
              "bitnamicoind" + config["environment"]["EXEEXT"],
          )
          fname_bitnamicoincli = os.path.join(
              config["environment"]["BUILDDIR"],
              "src",
              "bitnamicoin-cli" + config["environment"]["EXEEXT"],
          )
          self.options.bitnamicoind = os.getenv("BITNAMICOIND", default=fname_bitnamicoind)
          self.options.bitnamicoincli = os.getenv("BITNAMICOINCLI", default=fname_bitnamicoincli)
  
          os.environ['PATH'] = os.pathsep.join([
              os.path.join(config['environment']['BUILDDIR'], 'src'),
              os.path.join(config['environment']['BUILDDIR'], 'src', 'qt'), os.environ['PATH']
          ])
  
          # Set up temp directory and start logging
          if self.options.tmpdir:
              self.options.tmpdir = os.path.abspath(self.options.tmpdir)
              os.makedirs(self.options.tmpdir, exist_ok=False)
          else:
              self.options.tmpdir = tempfile.mkdtemp(prefix=TMPDIR_PREFIX)
          self._start_logging()
  
          # Seed the PRNG. Note that test runs are reproducible if and only if
          # a single thread accesses the PRNG. For more information, see
          # https://docs.python.org/3/library/random.html#notes-on-reproducibility.
          # The network thread shouldn't access random. If we need to change the
          # network thread to access randomness, it should instantiate its own
          # random.Random object.
          seed = self.options.randomseed
  
          if seed is None:
              seed = random.randrange(sys.maxsize)
          else:
              self.log.debug("User supplied random seed {}".format(seed))
  
          random.seed(seed)
          self.log.debug("PRNG seed is: {}".format(seed))
  
          self.log.debug('Setting up network thread')
          self.network_thread = NetworkThread()
          self.network_thread.start()
  
          if self.options.usecli:
              if not self.supports_cli:
                  raise SkipTest("--usecli specified but test does not support using CLI")
              self.skip_if_no_cli()
          self.skip_test_if_missing_module()
          self.setup_chain()
          self.setup_network()
  
          self.success = TestStatus.PASSED
  
      def shutdown(self):
          """Call this method to shut down the test framework object."""
  
          if self.success == TestStatus.FAILED and self.options.pdbonfailure:
              print("Testcase failed. Attaching python debugger. Enter ? for help")
              pdb.set_trace()
  
          self.log.debug('Closing down network thread')
          self.network_thread.close()
          if not self.options.noshutdown:
              self.log.info("Stopping nodes")
              if self.nodes:
                  self.stop_nodes()
          else:
              for node in self.nodes:
                  node.cleanup_on_exit = False
              self.log.info("Note: bitnamicoinds were not stopped and may still be running")
  
          should_clean_up = (
              not self.options.nocleanup and
              not self.options.noshutdown and
              self.success != TestStatus.FAILED and
              not self.options.perf
          )
          if should_clean_up:
              self.log.info("Cleaning up {} on exit".format(self.options.tmpdir))
              cleanup_tree_on_exit = True
          elif self.options.perf:
              self.log.warning("Not cleaning up dir {} due to perf data".format(self.options.tmpdir))
              cleanup_tree_on_exit = False
          else:
              self.log.warning("Not cleaning up dir {}".format(self.options.tmpdir))
              cleanup_tree_on_exit = False
  
          if self.success == TestStatus.PASSED:
              self.log.info("Tests successful")
              exit_code = TEST_EXIT_PASSED
          elif self.success == TestStatus.SKIPPED:
              self.log.info("Test skipped")
              exit_code = TEST_EXIT_SKIPPED
          else:
              self.log.error("Test failed. Test logging available at %s/test_framework.log", self.options.tmpdir)
              self.log.error("")
              self.log.error("Hint: Call {} '{}' to consolidate all logs".format(os.path.normpath(os.path.dirname(os.path.realpath(__file__)) + "/../combine_logs.py"), self.options.tmpdir))
              self.log.error("")
              self.log.error("If this failure happened unexpectedly or intermittently, please file a bug and provide a link or upload of the combined log.")
              self.log.error(self.config['environment']['PACKAGE_BUGREPORT'])
              self.log.error("")
              exit_code = TEST_EXIT_FAILED
          # Logging.shutdown will not remove stream- and filehandlers, so we must
          # do it explicitly. Handlers are removed so the next test run can apply
          # different log handler settings.
          # See: https://docs.python.org/3/library/logging.html#logging.shutdown
          for h in list(self.log.handlers):
              h.flush()
              h.close()
              self.log.removeHandler(h)
          rpc_logger = logging.getLogger("BitnamicoinRPC")
          for h in list(rpc_logger.handlers):
              h.flush()
              rpc_logger.removeHandler(h)
          if cleanup_tree_on_exit:
              shutil.rmtree(self.options.tmpdir)
  
          self.nodes.clear()
          return exit_code
  
      # Methods to override in subclass test scripts.
      def set_test_params(self):
          """Tests must this method to change default values for number of nodes, topology, etc"""
          raise NotImplementedError
  
      def add_options(self, parser):
          """Override this method to add command-line options to the test"""
          pass
  
      def skip_test_if_missing_module(self):
          """Override this method to skip a test if a module is not compiled"""
          pass
  
      def setup_chain(self):
          """Override this method to customize blockchain setup"""
          self.log.info("Initializing test directory " + self.options.tmpdir)
          if self.setup_clean_chain:
              self._initialize_chain_clean()
          else:
              self._initialize_chain()
  
      def setup_network(self):
          """Override this method to customize test network topology"""
          self.setup_nodes()
  
          # Connect the nodes as a "chain".  This allows us
          # to split the network between nodes 1 and 2 to get
          # two halves that can work on competing chains.
          #
          # Topology looks like this:
          # node0 <-- node1 <-- node2 <-- node3
          #
          # If all nodes are in IBD (clean chain from genesis), node0 is assumed to be the source of blocks (miner). To
          # ensure block propagation, all nodes will establish outgoing connections toward node0.
          # See fPreferredDownload in net_processing.
          #
          # If further outbound connections are needed, they can be added at the beginning of the test with e.g.
          # self.connect_nodes(1, 2)
          for i in range(self.num_nodes - 1):
              self.connect_nodes(i + 1, i)
          self.sync_all()
  
      def setup_nodes(self):
          """Override this method to customize test node setup"""
          extra_args = [[]] * self.num_nodes
          wallets = [[]] * self.num_nodes
          if hasattr(self, "extra_args"):
              extra_args = self.extra_args
              wallets = [[x for x in eargs if x.startswith('-wallet=')] for eargs in extra_args]
          extra_args = [x + ['-nowallet'] for x in extra_args]
          self.add_nodes(self.num_nodes, extra_args)
          self.start_nodes()
          for i, n in enumerate(self.nodes):
              n.extra_args.pop()
              if '-wallet=0' in n.extra_args or '-nowallet' in n.extra_args or '-disablewallet' in n.extra_args or not self.is_wallet_compiled():
                  continue
              if '-wallet=' not in wallets[i] and not any([x.startswith('-wallet=') for x in wallets[i]]):
                  wallets[i].append('-wallet=')
              for w in wallets[i]:
                  wallet_name = w.split('=', 1)[1]
                  n.createwallet(wallet_name=wallet_name, descriptors=self.options.descriptors)
          self.import_deterministic_coinbase_privkeys()
          if not self.setup_clean_chain:
              for n in self.nodes:
                  assert_equal(n.getblockchaininfo()["blocks"], 199)
              # To ensure that all nodes are out of IBD, the most recent block
              # must have a timestamp not too old (see IsInitialBlockDownload()).
              self.log.debug('Generate a block with current time')
              block_hash = self.nodes[0].generate(1)[0]
              block = self.nodes[0].getblock(blockhash=block_hash, verbosity=0)
              for n in self.nodes:
                  n.submitblock(block)
                  chain_info = n.getblockchaininfo()
                  assert_equal(chain_info["blocks"], 200)
                  assert_equal(chain_info["initialblockdownload"], False)
  
      def import_deterministic_coinbase_privkeys(self):
          for n in self.nodes:
              try:
                  n.getwalletinfo()
              except JSONRPCException as e:
                  assert str(e).startswith('Method not found')
                  continue
  
              n.importprivkey(privkey=n.get_deterministic_priv_key().key, label='coinbase')
  
      def run_test(self):
          """Tests must override this method to define test logic"""
          raise NotImplementedError
  
      # Public helper methods. These can be accessed by the subclass test scripts.
  
      def add_nodes(self, num_nodes: int, extra_args=None, *, rpchost=None, binary=None, binary_cli=None, versions=None):
          """Instantiate TestNode objects.
  
          Should only be called once after the nodes have been specified in
          set_test_params()."""
          def get_bin_from_version(version, bin_name, bin_default):
              if not version:
                  return bin_default
              return os.path.join(
                  self.options.previous_releases_path,
                  re.sub(
                      r'\.0$',
                      '',  # remove trailing .0 for point releases
                      'v{}.{}.{}.{}'.format(
                          (version % 100000000) // 1000000,
                          (version % 1000000) // 10000,
                          (version % 10000) // 100,
                          (version % 100) // 1,
                      ),
                  ),
                  'bin',
                  bin_name,
              )
  
          if self.bind_to_localhost_only:
              extra_confs = [["bind=127.0.0.1"]] * num_nodes
          else:
              extra_confs = [[]] * num_nodes
          if extra_args is None:
              extra_args = [[]] * num_nodes
          if versions is None:
              versions = [None] * num_nodes
          if binary is None:
              binary = [get_bin_from_version(v, 'bitnamicoind', self.options.bitnamicoind) for v in versions]
          if binary_cli is None:
              binary_cli = [get_bin_from_version(v, 'bitnamicoin-cli', self.options.bitnamicoincli) for v in versions]
          assert_equal(len(extra_confs), num_nodes)
          assert_equal(len(extra_args), num_nodes)
          assert_equal(len(versions), num_nodes)
          assert_equal(len(binary), num_nodes)
          assert_equal(len(binary_cli), num_nodes)
          for i in range(num_nodes):
              test_node_i = TestNode(
                  i,
                  get_datadir_path(self.options.tmpdir, i),
                  chain=self.chain,
                  rpchost=rpchost,
                  timewait=self.rpc_timeout,
                  timeout_factor=self.options.timeout_factor,
                  bitnamicoind=binary[i],
                  bitnamicoin_cli=binary_cli[i],
                  version=versions[i],
                  coverage_dir=self.options.coveragedir,
                  cwd=self.options.tmpdir,
                  extra_conf=extra_confs[i],
                  extra_args=extra_args[i],
                  use_cli=self.options.usecli,
                  start_perf=self.options.perf,
                  use_valgrind=self.options.valgrind,
                  descriptors=self.options.descriptors,
              )
              self.nodes.append(test_node_i)
              if not test_node_i.version_is_at_least(170000):
                  # adjust conf for pre 17
                  conf_file = test_node_i.bitnamicoinconf
                  with open(conf_file, 'r', encoding='utf8') as conf:
                      conf_data = conf.read()
                  with open(conf_file, 'w', encoding='utf8') as conf:
                      conf.write(conf_data.replace('[regtest]', ''))
  
      def start_node(self, i, *args, **kwargs):
          """Start a bitnamicoind"""
  
          node = self.nodes[i]
  
          node.start(*args, **kwargs)
          node.wait_for_rpc_connection()
  
          if self.options.coveragedir is not None:
              coverage.write_all_rpc_commands(self.options.coveragedir, node.rpc)
  
      def start_nodes(self, extra_args=None, *args, **kwargs):
          """Start multiple bitnamicoinds"""
  
          if extra_args is None:
              extra_args = [None] * self.num_nodes
          assert_equal(len(extra_args), self.num_nodes)
          try:
              for i, node in enumerate(self.nodes):
                  node.start(extra_args[i], *args, **kwargs)
              for node in self.nodes:
                  node.wait_for_rpc_connection()
          except:
              # If one node failed to start, stop the others
              self.stop_nodes()
              raise
  
          if self.options.coveragedir is not None:
              for node in self.nodes:
                  coverage.write_all_rpc_commands(self.options.coveragedir, node.rpc)
  
      def stop_node(self, i, expected_stderr='', wait=0):
          """Stop a bitnamicoind test node"""
          self.nodes[i].stop_node(expected_stderr, wait=wait)
          self.nodes[i].wait_until_stopped()
  
      def stop_nodes(self, wait=0):
          """Stop multiple bitnamicoind test nodes"""
          for node in self.nodes:
              # Issue RPC to stop nodes
              node.stop_node(wait=wait)
  
          for node in self.nodes:
              # Wait for nodes to stop
              node.wait_until_stopped()
  
      def restart_node(self, i, extra_args=None):
          """Stop and start a test node"""
          self.stop_node(i)
          self.start_node(i, extra_args)
  
      def wait_for_node_exit(self, i, timeout):
          self.nodes[i].process.wait(timeout)
  
      def connect_nodes(self, a, b):
          connect_nodes(self.nodes[a], b)
  
      def disconnect_nodes(self, a, b):
          disconnect_nodes(self.nodes[a], b)
  
      def split_network(self):
          """
          Split the network of four nodes into nodes 0/1 and 2/3.
          """
          self.disconnect_nodes(1, 2)
          self.sync_all(self.nodes[:2])
          self.sync_all(self.nodes[2:])
  
      def join_network(self):
          """
          Join the (previously split) network halves together.
          """
          self.connect_nodes(1, 2)
          self.sync_all()
  
      def sync_blocks(self, nodes=None, wait=1, timeout=60):
          """
          Wait until everybody has the same tip.
          sync_blocks needs to be called with an rpc_connections set that has least
          one node already synced to the latest, stable tip, otherwise there's a
          chance it might return before all nodes are stably synced.
          """
          rpc_connections = nodes or self.nodes
          timeout = int(timeout * self.options.timeout_factor)
          stop_time = time.time() + timeout
          while time.time() <= stop_time:
              best_hash = [x.getbestblockhash() for x in rpc_connections]
              if best_hash.count(best_hash[0]) == len(rpc_connections):
                  return
              # Check that each peer has at least one connection
              assert (all([len(x.getpeerinfo()) for x in rpc_connections]))
              time.sleep(wait)
          raise AssertionError("Block sync timed out after {}s:{}".format(
              timeout,
              "".join("\n  {!r}".format(b) for b in best_hash),
          ))
  
      def sync_mempools(self, nodes=None, wait=1, timeout=60, flush_scheduler=True):
          """
          Wait until everybody has the same transactions in their memory
          pools
          """
          rpc_connections = nodes or self.nodes
          timeout = int(timeout * self.options.timeout_factor)
          stop_time = time.time() + timeout
          while time.time() <= stop_time:
              pool = [set(r.getrawmempool()) for r in rpc_connections]
              if pool.count(pool[0]) == len(rpc_connections):
                  if flush_scheduler:
                      for r in rpc_connections:
                          r.syncwithvalidationinterfacequeue()
                  return
              # Check that each peer has at least one connection
              assert (all([len(x.getpeerinfo()) for x in rpc_connections]))
              time.sleep(wait)
          raise AssertionError("Mempool sync timed out after {}s:{}".format(
              timeout,
              "".join("\n  {!r}".format(m) for m in pool),
          ))
  
      def sync_all(self, nodes=None):
          self.sync_blocks(nodes)
          self.sync_mempools(nodes)
  
      def wait_until(self, test_function, timeout=60):
          return wait_until_helper(test_function, timeout=timeout, timeout_factor=self.options.timeout_factor)
  
      # Private helper methods. These should not be accessed by the subclass test scripts.
  
      def _start_logging(self):
          # Add logger and logging handlers
          self.log = logging.getLogger('TestFramework')
          self.log.setLevel(logging.DEBUG)
          # Create file handler to log all messages
          fh = logging.FileHandler(self.options.tmpdir + '/test_framework.log', encoding='utf-8')
          fh.setLevel(logging.DEBUG)
          # Create console handler to log messages to stderr. By default this logs only error messages, but can be configured with --loglevel.
          ch = logging.StreamHandler(sys.stdout)
          # User can provide log level as a number or string (eg DEBUG). loglevel was caught as a string, so try to convert it to an int
          ll = int(self.options.loglevel) if self.options.loglevel.isdigit() else self.options.loglevel.upper()
          ch.setLevel(ll)
          # Format logs the same as bitnamicoind's debug.log with microprecision (so log files can be concatenated and sorted)
          formatter = logging.Formatter(fmt='%(asctime)s.%(msecs)03d000Z %(name)s (%(levelname)s): %(message)s', datefmt='%Y-%m-%dT%H:%M:%S')
          formatter.converter = time.gmtime
          fh.setFormatter(formatter)
          ch.setFormatter(formatter)
          # add the handlers to the logger
          self.log.addHandler(fh)
          self.log.addHandler(ch)
  
          if self.options.trace_rpc:
              rpc_logger = logging.getLogger("BitnamicoinRPC")
              rpc_logger.setLevel(logging.DEBUG)
              rpc_handler = logging.StreamHandler(sys.stdout)
              rpc_handler.setLevel(logging.DEBUG)
              rpc_logger.addHandler(rpc_handler)
  
      def _initialize_chain(self):
          """Initialize a pre-mined blockchain for use by the test.
  
          Create a cache of a 199-block-long chain
          Afterward, create num_nodes copies from the cache."""
  
          CACHE_NODE_ID = 0  # Use node 0 to create the cache for all other nodes
          cache_node_dir = get_datadir_path(self.options.cachedir, CACHE_NODE_ID)
          assert self.num_nodes <= MAX_NODES
  
          if not os.path.isdir(cache_node_dir):
              self.log.debug("Creating cache directory {}".format(cache_node_dir))
  
              initialize_datadir(self.options.cachedir, CACHE_NODE_ID, self.chain)
              self.nodes.append(
                  TestNode(
                      CACHE_NODE_ID,
                      cache_node_dir,
                      chain=self.chain,
                      extra_conf=["bind=127.0.0.1"],
                      extra_args=['-disablewallet'],
                      rpchost=None,
                      timewait=self.rpc_timeout,
                      timeout_factor=self.options.timeout_factor,
                      bitnamicoind=self.options.bitnamicoind,
                      bitnamicoin_cli=self.options.bitnamicoincli,
                      coverage_dir=None,
                      cwd=self.options.tmpdir,
                      descriptors=self.options.descriptors,
                  ))
              self.start_node(CACHE_NODE_ID)
              cache_node = self.nodes[CACHE_NODE_ID]
  
              # Wait for RPC connections to be ready
              cache_node.wait_for_rpc_connection()
  
              # Set a time in the past, so that blocks don't end up in the future
              cache_node.setmocktime(cache_node.getblockheader(cache_node.getbestblockhash())['time'])
  
              # Create a 199-block-long chain; each of the 4 first nodes
              # gets 25 mature blocks and 25 immature.
              # The 4th node gets only 24 immature blocks so that the very last
              # block in the cache does not age too much (have an old tip age).
              # This is needed so that we are out of IBD when the test starts,
              # see the tip age check in IsInitialBlockDownload().
              for i in range(8):
                  cache_node.generatetoaddress(
                      nblocks=25 if i != 7 else 24,
                      address=TestNode.PRIV_KEYS[i % 4].address,
                  )
  
              assert_equal(cache_node.getblockchaininfo()["blocks"], 199)
  
              # Shut it down, and clean up cache directories:
              self.stop_nodes()
              self.nodes = []
  
              def cache_path(*paths):
                  return os.path.join(cache_node_dir, self.chain, *paths)
  
              os.rmdir(cache_path('wallets'))  # Remove empty wallets dir
              for entry in os.listdir(cache_path()):
                  if entry not in ['chainstate', 'blocks']:  # Only keep chainstate and blocks folder
                      os.remove(cache_path(entry))
  
          for i in range(self.num_nodes):
              self.log.debug("Copy cache directory {} to node {}".format(cache_node_dir, i))
              to_dir = get_datadir_path(self.options.tmpdir, i)
              shutil.copytree(cache_node_dir, to_dir)
              initialize_datadir(self.options.tmpdir, i, self.chain)  # Overwrite port/rpcport in bitnamicoin.conf
  
      def _initialize_chain_clean(self):
          """Initialize empty blockchain for use by the test.
  
          Create an empty blockchain and num_nodes wallets.
          Useful if a test case wants complete control over initialization."""
          for i in range(self.num_nodes):
              initialize_datadir(self.options.tmpdir, i, self.chain)
  
      def skip_if_no_py3_zmq(self):
          """Attempt to import the zmq package and skip the test if the import fails."""
          try:
              import zmq  # noqa
          except ImportError:
              raise SkipTest("python3-zmq module not available.")
  
      def skip_if_no_bitnamicoind_zmq(self):
          """Skip the running test if bitnamicoind has not been compiled with zmq support."""
          if not self.is_zmq_compiled():
              raise SkipTest("bitnamicoind has not been built with zmq enabled.")
  
      def skip_if_no_wallet(self):
          """Skip the running test if wallet has not been compiled."""
          if not self.is_wallet_compiled():
              raise SkipTest("wallet has not been compiled.")
  
      def skip_if_no_wallet_tool(self):
          """Skip the running test if bitnamicoin-wallet has not been compiled."""
          if not self.is_wallet_tool_compiled():
              raise SkipTest("bitnamicoin-wallet has not been compiled")
  
      def skip_if_no_cli(self):
          """Skip the running test if bitnamicoin-cli has not been compiled."""
          if not self.is_cli_compiled():
              raise SkipTest("bitnamicoin-cli has not been compiled.")
  
      def skip_if_no_previous_releases(self):
          """Skip the running test if previous releases are not available."""
          if not self.has_previous_releases():
              raise SkipTest("previous releases not available or disabled")
  
      def has_previous_releases(self):
          """Checks whether previous releases are present and enabled."""
          if not os.path.isdir(self.options.previous_releases_path):
              if self.options.prev_releases:
                  raise AssertionError("Force test of previous releases but releases missing: {}".format(
                      self.options.previous_releases_path))
          return self.options.prev_releases
  
      def is_cli_compiled(self):
          """Checks whether bitnamicoin-cli was compiled."""
          return self.config["components"].getboolean("ENABLE_CLI")
  
      def is_wallet_compiled(self):
          """Checks whether the wallet module was compiled."""
          return self.config["components"].getboolean("ENABLE_WALLET")
  
      def is_wallet_tool_compiled(self):
          """Checks whether bitnamicoin-wallet was compiled."""
          return self.config["components"].getboolean("ENABLE_WALLET_TOOL")
  
      def is_zmq_compiled(self):
          """Checks whether the zmq module was compiled."""
          return self.config["components"].getboolean("ENABLE_ZMQ")
  