lbry-sdk/torba/server/env.py
binaryflesh 6788e09ae9 PEP-257 docstrings
Signed-off-by: binaryflesh <logan.campos123@gmail.com>
2019-04-16 06:24:08 -04:00

247 lines
9.4 KiB
Python

# Copyright (c) 2016, Neil Booth
#
# All rights reserved.
#
# See the file "LICENCE" for information about the copyright
# and warranty status of this software.
import re
import resource
from os import environ
from collections import namedtuple
from ipaddress import ip_address
from torba.server.util import class_logger
from torba.server.coins import Coin
import torba.server.util as lib_util
NetIdentity = namedtuple('NetIdentity', 'host tcp_port ssl_port nick_suffix')
class Env:
# Peer discovery
PD_OFF, PD_SELF, PD_ON = range(3)
class Error(Exception):
pass
def __init__(self, coin=None):
self.logger = class_logger(__name__, self.__class__.__name__)
self.allow_root = self.boolean('ALLOW_ROOT', False)
self.host = self.default('HOST', 'localhost')
self.rpc_host = self.default('RPC_HOST', 'localhost')
self.loop_policy = self.event_loop_policy()
self.obsolete(['UTXO_MB', 'HIST_MB', 'NETWORK'])
self.db_dir = self.required('DB_DIRECTORY')
self.db_engine = self.default('DB_ENGINE', 'leveldb')
self.daemon_url = self.required('DAEMON_URL')
if coin is not None:
assert issubclass(coin, Coin)
self.coin = coin
else:
coin_name = self.required('COIN').strip()
network = self.default('NET', 'mainnet').strip()
self.coin = Coin.lookup_coin_class(coin_name, network)
self.cache_MB = self.integer('CACHE_MB', 1200)
self.host = self.default('HOST', 'localhost')
self.reorg_limit = self.integer('REORG_LIMIT', self.coin.REORG_LIMIT)
# Server stuff
self.tcp_port = self.integer('TCP_PORT', None)
self.ssl_port = self.integer('SSL_PORT', None)
if self.ssl_port:
self.ssl_certfile = self.required('SSL_CERTFILE')
self.ssl_keyfile = self.required('SSL_KEYFILE')
self.rpc_port = self.integer('RPC_PORT', 8000)
self.max_subscriptions = self.integer('MAX_SUBSCRIPTIONS', 10000)
self.banner_file = self.default('BANNER_FILE', None)
self.tor_banner_file = self.default('TOR_BANNER_FILE', self.banner_file)
self.anon_logs = self.boolean('ANON_LOGS', False)
self.log_sessions = self.integer('LOG_SESSIONS', 3600)
# Peer discovery
self.peer_discovery = self.peer_discovery_enum()
self.peer_announce = self.boolean('PEER_ANNOUNCE', True)
self.force_proxy = self.boolean('FORCE_PROXY', False)
self.tor_proxy_host = self.default('TOR_PROXY_HOST', 'localhost')
self.tor_proxy_port = self.integer('TOR_PROXY_PORT', None)
# The electrum client takes the empty string as unspecified
self.donation_address = self.default('DONATION_ADDRESS', '')
# Server limits to help prevent DoS
self.max_send = self.integer('MAX_SEND', 1000000)
self.max_subs = self.integer('MAX_SUBS', 250000)
self.max_sessions = self.sane_max_sessions()
self.max_session_subs = self.integer('MAX_SESSION_SUBS', 50000)
self.bandwidth_limit = self.integer('BANDWIDTH_LIMIT', 2000000)
self.session_timeout = self.integer('SESSION_TIMEOUT', 600)
self.drop_client = self.custom("DROP_CLIENT", None, re.compile)
# Identities
clearnet_identity = self.clearnet_identity()
tor_identity = self.tor_identity(clearnet_identity)
self.identities = [identity
for identity in (clearnet_identity, tor_identity)
if identity is not None]
@classmethod
def default(cls, envvar, default):
return environ.get(envvar, default)
@classmethod
def boolean(cls, envvar, default):
default = 'Yes' if default else ''
return bool(cls.default(envvar, default).strip())
@classmethod
def required(cls, envvar):
value = environ.get(envvar)
if value is None:
raise cls.Error('required envvar {} not set'.format(envvar))
return value
@classmethod
def integer(cls, envvar, default):
value = environ.get(envvar)
if value is None:
return default
try:
return int(value)
except Exception:
raise cls.Error('cannot convert envvar {} value {} to an integer'
.format(envvar, value))
@classmethod
def custom(cls, envvar, default, parse):
value = environ.get(envvar)
if value is None:
return default
try:
return parse(value)
except Exception as e:
raise cls.Error('cannot parse envvar {} value {}'
.format(envvar, value)) from e
@classmethod
def obsolete(cls, envvars):
bad = [envvar for envvar in envvars if environ.get(envvar)]
if bad:
raise cls.Error('remove obsolete environment variables {}'
.format(bad))
def event_loop_policy(self):
policy = self.default('EVENT_LOOP_POLICY', None)
if policy is None:
return None
if policy == 'uvloop':
import uvloop
return uvloop.EventLoopPolicy()
raise self.Error('unknown event loop policy "{}"'.format(policy))
def cs_host(self, *, for_rpc):
"""Returns the 'host' argument to pass to asyncio's create_server
call. The result can be a single host name string, a list of
host name strings, or an empty string to bind to all interfaces.
If rpc is True the host to use for the RPC server is returned.
Otherwise the host to use for SSL/TCP servers is returned.
"""
host = self.rpc_host if for_rpc else self.host
result = [part.strip() for part in host.split(',')]
if len(result) == 1:
result = result[0]
# An empty result indicates all interfaces, which we do not
# permitted for an RPC server.
if for_rpc and not result:
result = 'localhost'
if result == 'localhost':
# 'localhost' resolves to ::1 (ipv6) on many systems, which fails on default setup of
# docker, using 127.0.0.1 instead forces ipv4
result = '127.0.0.1'
return result
def sane_max_sessions(self):
"""Return the maximum number of sessions to permit. Normally this
is MAX_SESSIONS. However, to prevent open file exhaustion, ajdust
downwards if running with a small open file rlimit."""
env_value = self.integer('MAX_SESSIONS', 1000)
nofile_limit = resource.getrlimit(resource.RLIMIT_NOFILE)[0]
# We give the DB 250 files; allow ElectrumX 100 for itself
value = max(0, min(env_value, nofile_limit - 350))
if value < env_value:
self.logger.warning('lowered maximum sessions from {:,d} to {:,d} '
'because your open file limit is {:,d}'
.format(env_value, value, nofile_limit))
return value
def clearnet_identity(self):
host = self.default('REPORT_HOST', None)
if host is None:
return None
try:
ip = ip_address(host)
except ValueError:
bad = (not lib_util.is_valid_hostname(host)
or host.lower() == 'localhost')
else:
bad = (ip.is_multicast or ip.is_unspecified
or (ip.is_private and self.peer_announce))
if bad:
raise self.Error('"{}" is not a valid REPORT_HOST'.format(host))
tcp_port = self.integer('REPORT_TCP_PORT', self.tcp_port) or None
ssl_port = self.integer('REPORT_SSL_PORT', self.ssl_port) or None
if tcp_port == ssl_port:
raise self.Error('REPORT_TCP_PORT and REPORT_SSL_PORT '
'both resolve to {}'.format(tcp_port))
return NetIdentity(
host,
tcp_port,
ssl_port,
''
)
def tor_identity(self, clearnet):
host = self.default('REPORT_HOST_TOR', None)
if host is None:
return None
if not host.endswith('.onion'):
raise self.Error('tor host "{}" must end with ".onion"'
.format(host))
def port(port_kind):
"""Returns the clearnet identity port, if any and not zero,
otherwise the listening port."""
result = 0
if clearnet:
result = getattr(clearnet, port_kind)
return result or getattr(self, port_kind)
tcp_port = self.integer('REPORT_TCP_PORT_TOR',
port('tcp_port')) or None
ssl_port = self.integer('REPORT_SSL_PORT_TOR',
port('ssl_port')) or None
if tcp_port == ssl_port:
raise self.Error('REPORT_TCP_PORT_TOR and REPORT_SSL_PORT_TOR '
'both resolve to {}'.format(tcp_port))
return NetIdentity(
host,
tcp_port,
ssl_port,
'_tor',
)
def hosts_dict(self):
return {identity.host: {'tcp_port': identity.tcp_port,
'ssl_port': identity.ssl_port}
for identity in self.identities}
def peer_discovery_enum(self):
pd = self.default('PEER_DISCOVERY', 'on').strip().lower()
if pd in ('off', ''):
return self.PD_OFF
elif pd == 'self':
return self.PD_SELF
else:
return self.PD_ON