dash/test/functional/test_framework/test_node.py

#!/usr/bin/env python3
# Copyright (c) 2017 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Class for dashd node under test"""

import decimal
import errno
import http.client
import json
import logging
import os
import subprocess
import time

from .authproxy import JSONRPCException
from .mininode import NodeConn
from .util import (
    assert_equal,
    get_rpc_proxy,
    rpc_url,
    wait_until,
    p2p_port,
)

BITCOIND_PROC_WAIT_TIMEOUT = 60

class TestNode():
    """A class for representing a dashd node under test.

    This class contains:

    - state about the node (whether it's running, etc)
    - a Python subprocess.Popen object representing the running process
    - an RPC connection to the node
    - one or more P2P connections to the node


    To make things easier for the test writer, any unrecognised messages will
    be dispatched to the RPC connection."""

    def __init__(self, i, dirname, extra_args, rpchost, timewait, binary, stderr, mocktime, coverage_dir):
        self.index = i
        self.datadir = os.path.join(dirname, "node" + str(i))
        self.rpchost = rpchost
        if timewait:
            self.rpc_timeout = timewait
        else:
            # Wait for up to 60 seconds for the RPC server to respond
            self.rpc_timeout = 60
        if binary is None:
            self.binary = os.getenv("BITCOIND", "dashd")
        else:
            self.binary = binary
        self.stderr = stderr
        self.coverage_dir = coverage_dir
        # Most callers will just need to add extra args to the standard list below. For those callers that need more flexibity, they can just set the args property directly.
        self.extra_args = extra_args
        self.args = [self.binary, "-datadir=" + self.datadir, "-server", "-keypool=1", "-discover=0", "-rest", "-logtimemicros", "-debug", "-debugexclude=libevent", "-debugexclude=leveldb", "-mocktime=" + str(mocktime), "-uacomment=testnode%d" % i]

        self.cli = TestNodeCLI(os.getenv("BITCOINCLI", "dash-cli"), self.datadir)

        # Don't try auto backups (they fail a lot when running tests)
        self.args.append("-createwalletbackups=0")

        self.running = False
        self.process = None
        self.rpc_connected = False
        self.rpc = None
        self.url = None
        self.log = logging.getLogger('TestFramework.node%d' % i)

        self.p2ps = []

    def __getattr__(self, name):
        """Dispatches any unrecognised messages to the RPC connection."""
        assert self.rpc_connected and self.rpc is not None, "Error: no RPC connection"
        return getattr(self.rpc, name)

    def start(self, extra_args=None, stderr=None):
        """Start the node."""
        if extra_args is None:
            extra_args = self.extra_args
        if stderr is None:
            stderr = self.stderr
        self.process = subprocess.Popen(self.args + extra_args, stderr=stderr)
        self.running = True
        self.log.debug("dashd started, waiting for RPC to come up")

    def wait_for_rpc_connection(self):
        """Sets up an RPC connection to the dashd process. Returns False if unable to connect."""
        # Poll at a rate of four times per second
        poll_per_s = 4
        for _ in range(poll_per_s * self.rpc_timeout):
            assert self.process.poll() is None, "dashd exited with status %i during initialization" % self.process.returncode
            try:
                self.rpc = get_rpc_proxy(rpc_url(self.datadir, self.index, self.rpchost), self.index, timeout=self.rpc_timeout, coveragedir=self.coverage_dir)
                self.rpc.getblockcount()
                # If the call to getblockcount() succeeds then the RPC connection is up
                self.rpc_connected = True
                self.url = self.rpc.url
                self.log.debug("RPC successfully started")
                return
            except IOError as e:
                if e.errno != errno.ECONNREFUSED:  # Port not yet open?
                    raise  # unknown IO error
            except JSONRPCException as e:  # Initialization phase
                # -28 RPC in warmup
                # -342 Service unavailable, RPC server started but is shutting down due to error
                if e.error['code'] != -28 and e.error['code'] != -342:
                    raise  # unknown JSON RPC exception
            except ValueError as e:  # cookie file not found and no rpcuser or rpcassword. dashd still starting
                if "No RPC credentials" not in str(e):
                    raise
            time.sleep(1.0 / poll_per_s)
        raise AssertionError("Unable to connect to dashd")

    def get_wallet_rpc(self, wallet_name):
        assert self.rpc_connected
        assert self.rpc
        wallet_path = "wallet/%s" % wallet_name
        return self.rpc / wallet_path

    def stop_node(self, wait=0):
        """Stop the node."""
        if not self.running:
            return
        self.log.debug("Stopping node")
        try:
            self.stop(wait=wait)
        except http.client.CannotSendRequest:
            self.log.exception("Unable to stop node.")
        del self.p2ps[:]

    def is_node_stopped(self):
        """Checks whether the node has stopped.

        Returns True if the node has stopped. False otherwise.
        This method is responsible for freeing resources (self.process)."""
        if not self.running:
            return True
        return_code = self.process.poll()
        if return_code is None:
            return False

        # process has stopped. Assert that it didn't return an error code.
        assert_equal(return_code, 0)
        self.running = False
        self.process = None
        self.rpc_connected = False
        self.rpc = None
        self.log.debug("Node stopped")
        return True

    def wait_until_stopped(self, timeout=BITCOIND_PROC_WAIT_TIMEOUT):
        wait_until(self.is_node_stopped, timeout=timeout)

    def node_encrypt_wallet(self, passphrase):
        """"Encrypts the wallet.

        This causes dashd to shutdown, so this method takes
        care of cleaning up resources."""
        self.encryptwallet(passphrase)
        self.wait_until_stopped()

    def add_p2p_connection(self, p2p_conn, **kwargs):
        """Add a p2p connection to the node.

        This method adds the p2p connection to the self.p2ps list and also
        returns the connection to the caller."""
        if 'dstport' not in kwargs:
            kwargs['dstport'] = p2p_port(self.index)
        if 'dstaddr' not in kwargs:
            kwargs['dstaddr'] = '127.0.0.1'
        self.p2ps.append(p2p_conn)
        kwargs.update({'rpc': self.rpc, 'callback': p2p_conn})
        p2p_conn.add_connection(NodeConn(**kwargs))

        return p2p_conn

    @property
    def p2p(self):
        """Return the first p2p connection

        Convenience property - most tests only use a single p2p connection to each
        node, so this saves having to write node.p2ps[0] many times."""
        assert self.p2ps, "No p2p connection"
        return self.p2ps[0]

    def disconnect_p2ps(self):
        """Close all p2p connections to the node."""
        for p in self.p2ps:
            # Connection could have already been closed by other end.
            if p.connection is not None:
                p.connection.disconnect_node()
        self.p2ps = []


class TestNodeCLI():
    """Interface to bitcoin-cli for an individual node"""

    def __init__(self, binary, datadir):
        self.args = []
        self.binary = binary
        self.datadir = datadir
        self.input = None

    def __call__(self, *args, input=None):
        # TestNodeCLI is callable with bitcoin-cli command-line args
        self.args = [str(arg) for arg in args]
        self.input = input
        return self

    def __getattr__(self, command):
        def dispatcher(*args, **kwargs):
            return self.send_cli(command, *args, **kwargs)
        return dispatcher

    def send_cli(self, command, *args, **kwargs):
        """Run bitcoin-cli command. Deserializes returned string as python object."""

        pos_args = [str(arg) for arg in args]
        named_args = [str(key) + "=" + str(value) for (key, value) in kwargs.items()]
        assert not (pos_args and named_args), "Cannot use positional arguments and named arguments in the same bitcoin-cli call"
        p_args = [self.binary, "-datadir=" + self.datadir] + self.args
        if named_args:
            p_args += ["-named"]
        p_args += [command] + pos_args + named_args
        process = subprocess.Popen(p_args, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True)
        cli_stdout, cli_stderr = process.communicate(input=self.input)
        returncode = process.poll()
        if returncode:
            # Ignore cli_stdout, raise with cli_stderr
            raise subprocess.CalledProcessError(returncode, self.binary, output=cli_stderr)
        return json.loads(cli_stdout, parse_float=decimal.Decimal)