text: #!/usr/bin/env python3
  # Copyright (c) 2014-2016 The Bitcoin 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 logging
  import optparse
  import os
  import sys
  import shutil
  import tempfile
  import traceback
  
  from .util import (
      initialize_chain,
      start_nodes,
      connect_nodes_bi,
      disconnect_nodes,
      sync_blocks,
      sync_mempools,
      stop_nodes,
      stop_node,
      enable_coverage,
      check_json_precision,
      initialize_chain_clean,
      PortSeed,
  )
  from .authproxy import JSONRPCException
  from .outputchecker import OutputChecker
  
  
  class BitcoinTestFramework(object):
  
      def __init__(self):
          self.num_nodes = 4
          self.setup_clean_chain = False
          self.nodes = None
  
      def run_test(self):
          raise NotImplementedError
  
      def add_options(self, parser):
          pass
  
      def setup_chain(self):
          self.log.info("Initializing test directory " + self.options.tmpdir)
          if self.setup_clean_chain:
              initialize_chain_clean(self.options.tmpdir, self.num_nodes)
          else:
              initialize_chain(
                  self.options.tmpdir, self.num_nodes, self.options.cachedir)
  
      def stop_node(self, num_node):
          stop_node(self.nodes[num_node], num_node)
  
      def setup_nodes(self):
          '''
          Starts up the nodes.
          '''
          extra_args = None
          if hasattr(self, "extra_args"):
              extra_args = self.extra_args
          self.nodes = start_nodes(
              self.num_nodes, self.options.tmpdir, extra_args)
  
      def setup_network(self):
          '''
          Sets up network including starting up nodes.
          '''
          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.
  
          for i in range(self.num_nodes - 1):
              connect_nodes_bi(self.nodes, i, i + 1)
          self.sync_all()
  
      def split_network(self):
          """
          Split the network of four nodes into nodes 0/1 and 2/3.
          """
          disconnect_nodes(self.nodes[1], 2)
          disconnect_nodes(self.nodes[2], 1)
          self.sync_all([self.nodes[:2], self.nodes[2:]])
  
      def sync_all(self, node_groups=None):
          if not node_groups:
              node_groups = [self.nodes]
  
          [sync_blocks(group) for group in node_groups]
          [sync_mempools(group) for group in node_groups]
  
      def join_network(self):
          """
          Join the (previously split) network halves together.
          """
          connect_nodes_bi(self.nodes, 1, 2)
          self.sync_all()
  
      def main(self):
  
          parser = optparse.OptionParser(usage="%prog [options]")
          parser.add_option(
              "--nocleanup", dest="nocleanup", default=False, action="store_true",
                            help="Leave bitcoinds and test.* datadir on exit or error")
          parser.add_option(
              "--noshutdown", dest="noshutdown", default=False, action="store_true",
                            help="Don't stop bitcoinds after the test execution")
          parser.add_option(
              "--srcdir", dest="srcdir", default=os.path.normpath(os.path.dirname(os.path.realpath(__file__)) + "/../../../src"),
                            help="Source directory containing bitcoind/bitcoin-cli (default: %default)")
          parser.add_option(
              "--cachedir", dest="cachedir", default=os.path.normpath(os.path.dirname(os.path.realpath(__file__)) + "/../../cache"),
                            help="Directory for caching pregenerated datadirs")
          parser.add_option(
              "--tmpdir", dest="tmpdir", default=tempfile.mkdtemp(prefix="test"),
                            help="Root directory for datadirs")
          parser.add_option("-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_option(
              "--tracerpc", dest="trace_rpc", default=False, action="store_true",
                            help="Print out all RPC calls as they are made")
          parser.add_option(
              "--portseed", dest="port_seed", default=os.getpid(), type='int',
                            help="The seed to use for assigning port numbers (default: current process id)")
          parser.add_option("--coveragedir", dest="coveragedir",
                            help="Write tested RPC commands into this directory")
          self.add_options(parser)
          (self.options, self.args) = parser.parse_args()
  
          # backup dir variable for removal at cleanup
          self.options.root, self.options.tmpdir = self.options.tmpdir, self.options.tmpdir + \
              '/' + str(self.options.port_seed)
  
          if self.options.coveragedir:
              enable_coverage(self.options.coveragedir)
  
          PortSeed.n = self.options.port_seed
  
          os.environ['PATH'] = self.options.srcdir + ":" + \
              self.options.srcdir + "/qt:" + os.environ['PATH']
  
          check_json_precision()
  
          # Set up temp directory and start logging
          os.makedirs(self.options.tmpdir, exist_ok=False)
          self._start_logging()
  
          success = False
  
          try:
              self.setup_chain()
              self.setup_network()
              self.run_test()
              success = True
          except JSONRPCException as e:
              self.log.exception("JSONRPC error")
          except AssertionError as e:
              self.log.exception("Assertion failed")
          except KeyError as e:
              self.log.exception("Key error")
          except Exception as e:
              self.log.exception("Unexpected exception caught during testing")
          except KeyboardInterrupt as e:
              self.log.warning("Exiting after keyboard interrupt")
  
          if not self.options.noshutdown:
              self.log.info("Stopping nodes")
              stop_nodes(self.nodes)
          else:
              self.log.info(
                  "Note: bitcoinds were not stopped and may still be running")
  
          if not self.options.nocleanup and not self.options.noshutdown and success:
              self.log.info("Cleaning up")
              shutil.rmtree(self.options.tmpdir)
              if not os.listdir(self.options.root):
                  os.rmdir(self.options.root)
          else:
              self.log.warning("Not cleaning up dir %s" % self.options.tmpdir)
              if os.getenv("PYTHON_DEBUG", ""):
                  # Dump the end of the debug logs, to aid in debugging rare
                  # travis failures.
                  import glob
                  filenames = glob.glob(
                      self.options.tmpdir + "/node*/regtest/debug.log")
                  MAX_LINES_TO_PRINT = 1000
                  for f in filenames:
                      print("From", f, ":")
                      from collections import deque
                      print("".join(deque(open(f), MAX_LINES_TO_PRINT)))
          if success:
              self.log.info("Tests successful")
              sys.exit(0)
          else:
              self.log.error(
                  "Test failed. Test logging available at %s/test_framework.log", self.options.tmpdir)
              logging.shutdown()
              sys.exit(1)
  
      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')
          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 bitcoind's debug.log with microprecision (so
          # log files can be concatenated and sorted)
          formatter = logging.Formatter(
              fmt='%(asctime)s.%(msecs)03d000 %(name)s (%(levelname)s): %(message)s', datefmt='%Y-%m-%d %H:%M:%S')
          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("BitcoinRPC")
              rpc_logger.setLevel(logging.DEBUG)
              rpc_handler = logging.StreamHandler(sys.stdout)
              rpc_handler.setLevel(logging.DEBUG)
              rpc_logger.addHandler(rpc_handler)
  
  # Test framework for doing p2p comparison testing, which sets up some bitcoind
  # binaries:
  # 1 binary: test binary
  # 2 binaries: 1 test binary, 1 ref binary
  # n>2 binaries: 1 test binary, n-1 ref binaries
  
  
  class ComparisonTestFramework(BitcoinTestFramework):
  
      def __init__(self):
          super().__init__()
          self.num_nodes = 2
          self.setup_clean_chain = True
  
      def add_options(self, parser):
          parser.add_option("--testbinary", dest="testbinary",
                            default=os.getenv("BITCOIND", "bitcoind"),
                            help="bitcoind binary to test")
          parser.add_option("--refbinary", dest="refbinary",
                            default=os.getenv("BITCOIND", "bitcoind"),
                            help="bitcoind binary to use for reference nodes (if any)")
  
      def setup_network(self):
          extra_args = [['-whitelist=127.0.0.1']] * self.num_nodes
          if hasattr(self, "extra_args"):
              extra_args = self.extra_args
          self.nodes = start_nodes(
              self.num_nodes, self.options.tmpdir, extra_args,
              binary=[self.options.testbinary] +
              [self.options.refbinary] * (self.num_nodes - 1))
  