lbry-sdk/lbrynet/extras/daemon/Components.py

737 lines
29 KiB
Python

import os
import asyncio
import aiohttp
import logging
import treq
import math
import binascii
from hashlib import sha256
from types import SimpleNamespace
from twisted.internet import defer, reactor, error
from aioupnp import __version__ as aioupnp_version
from aioupnp.upnp import UPnP
from aioupnp.fault import UPnPError
import lbrynet.schema
from lbrynet import conf
from lbrynet.extras.compat import d2f
from lbrynet.blob.EncryptedFileManager import EncryptedFileManager
from lbrynet.blob.client.EncryptedFileDownloader import EncryptedFileSaverFactory
from lbrynet.blob.client.EncryptedFileOptions import add_lbry_file_to_sd_identifier
from lbrynet.dht.node import Node
from lbrynet.extras.daemon.Component import Component
from lbrynet.extras.daemon.ExchangeRateManager import ExchangeRateManager
from lbrynet.extras.daemon.storage import SQLiteStorage
from lbrynet.extras.daemon.HashAnnouncer import DHTHashAnnouncer
from lbrynet.extras.reflector.server.server import ReflectorServerFactory
from lbrynet.extras.wallet import LbryWalletManager
from lbrynet.extras.wallet import Network
from lbrynet.utils import generate_id
from lbrynet.p2p.PaymentRateManager import OnlyFreePaymentsManager
from lbrynet.p2p.RateLimiter import RateLimiter
from lbrynet.p2p.BlobManager import DiskBlobManager
from lbrynet.p2p.StreamDescriptor import StreamDescriptorIdentifier, EncryptedFileStreamType
from lbrynet.p2p.server.BlobRequestHandler import BlobRequestHandlerFactory
from lbrynet.p2p.server.ServerProtocol import ServerProtocolFactory
log = logging.getLogger(__name__)
# settings must be initialized before this file is imported
DATABASE_COMPONENT = "database"
BLOB_COMPONENT = "blob_manager"
HEADERS_COMPONENT = "blockchain_headers"
WALLET_COMPONENT = "wallet"
DHT_COMPONENT = "dht"
HASH_ANNOUNCER_COMPONENT = "hash_announcer"
FILE_MANAGER_COMPONENT = "file_manager"
PEER_PROTOCOL_SERVER_COMPONENT = "peer_protocol_server"
REFLECTOR_COMPONENT = "reflector"
UPNP_COMPONENT = "upnp"
EXCHANGE_RATE_MANAGER_COMPONENT = "exchange_rate_manager"
RATE_LIMITER_COMPONENT = "rate_limiter"
PAYMENT_RATE_COMPONENT = "payment_rate_manager"
async def gather_dict(tasks: dict):
async def wait_value(key, value):
return key, await value
return dict(await asyncio.gather(*(
wait_value(*kv) for kv in tasks.items()
)))
async def get_external_ip(): # used if upnp is disabled or non-functioning
try:
async with aiohttp.ClientSession() as session:
async with session.get("https://api.lbry.io/ip") as resp:
response = await resp.json()
if response['success']:
return response['data']['ip']
except Exception as e:
pass
class DatabaseComponent(Component):
component_name = DATABASE_COMPONENT
def __init__(self, component_manager):
super().__init__(component_manager)
self.storage = None
@property
def component(self):
return self.storage
@staticmethod
def get_current_db_revision():
return 9
@staticmethod
def get_revision_filename():
return conf.settings.get_db_revision_filename()
@staticmethod
def _write_db_revision_file(version_num):
with open(conf.settings.get_db_revision_filename(), mode='w') as db_revision:
db_revision.write(str(version_num))
async def start(self):
# check directories exist, create them if they don't
log.info("Loading databases")
if not os.path.exists(self.get_revision_filename()):
log.warning("db_revision file not found. Creating it")
self._write_db_revision_file(self.get_current_db_revision())
# check the db migration and run any needed migrations
with open(self.get_revision_filename(), "r") as revision_read_handle:
old_revision = int(revision_read_handle.read().strip())
if old_revision > self.get_current_db_revision():
raise Exception('This version of lbrynet is not compatible with the database\n'
'Your database is revision %i, expected %i' %
(old_revision, self.get_current_db_revision()))
if old_revision < self.get_current_db_revision():
from lbrynet.extras.daemon.migrator import dbmigrator
log.info("Upgrading your databases (revision %i to %i)", old_revision, self.get_current_db_revision())
await asyncio.get_event_loop().run_in_executor(
None, dbmigrator.migrate_db, conf.settings.data_dir, old_revision, self.get_current_db_revision()
)
self._write_db_revision_file(self.get_current_db_revision())
log.info("Finished upgrading the databases.")
self.storage = SQLiteStorage(
os.path.join(conf.settings.data_dir, "lbrynet.sqlite")
)
await self.storage.open()
async def stop(self):
await self.storage.close()
self.storage = None
HEADERS_URL = "https://headers.lbry.io/blockchain_headers_latest"
HEADER_SIZE = 112
class HeadersComponent(Component):
component_name = HEADERS_COMPONENT
def __init__(self, component_manager):
super().__init__(component_manager)
self.headers_dir = os.path.join(conf.settings.wallet_dir, 'lbc_mainnet')
self.headers_file = os.path.join(self.headers_dir, 'headers')
self.old_file = os.path.join(conf.settings.wallet_dir, 'blockchain_headers')
self._downloading_headers = None
self._headers_progress_percent = 0
@property
def component(self):
return self
async def get_status(self):
return {} if not self._downloading_headers else {
'downloading_headers': self._downloading_headers,
'download_progress': self._headers_progress_percent
}
@defer.inlineCallbacks
def fetch_headers_from_s3(self):
def collector(data, h_file):
h_file.write(data)
local_size = float(h_file.tell())
final_size = float(final_size_after_download)
self._headers_progress_percent = math.ceil(local_size / final_size * 100)
local_header_size = self.local_header_file_size()
resume_header = {"Range": f"bytes={local_header_size}-"}
response = yield treq.get(HEADERS_URL, headers=resume_header)
got_406 = response.code == 406 # our file is bigger
final_size_after_download = response.length + local_header_size
if got_406:
log.warning("s3 is more out of date than we are")
# should have something to download and a final length divisible by the header size
elif final_size_after_download and not final_size_after_download % HEADER_SIZE:
s3_height = (final_size_after_download / HEADER_SIZE) - 1
local_height = self.local_header_file_height()
if s3_height > local_height:
if local_header_size:
log.info("Resuming download of %i bytes from s3", response.length)
with open(self.headers_file, "a+b") as headers_file:
yield treq.collect(response, lambda d: collector(d, headers_file))
else:
with open(self.headers_file, "wb") as headers_file:
yield treq.collect(response, lambda d: collector(d, headers_file))
log.info("fetched headers from s3 (s3 height: %i), now verifying integrity after download.", s3_height)
self._check_header_file_integrity()
else:
log.warning("s3 is more out of date than we are")
else:
log.error("invalid size for headers from s3")
def local_header_file_height(self):
return max((self.local_header_file_size() / HEADER_SIZE) - 1, 0)
def local_header_file_size(self):
if os.path.isfile(self.headers_file):
return os.stat(self.headers_file).st_size
return 0
async def get_remote_height(self):
ledger = SimpleNamespace()
ledger.config = {
'default_servers': conf.settings['lbryum_servers'],
'data_path': conf.settings.wallet_dir
}
net = Network(ledger)
first_connection = net.on_connected.first
asyncio.ensure_future(net.start())
await first_connection
remote_height = await net.get_server_height()
await net.stop()
return remote_height
async def should_download_headers_from_s3(self):
if conf.settings['blockchain_name'] != "lbrycrd_main":
return False
self._check_header_file_integrity()
s3_headers_depth = conf.settings['s3_headers_depth']
if not s3_headers_depth:
return False
local_height = self.local_header_file_height()
remote_height = await self.get_remote_height()
log.info("remote height: %i, local height: %i", remote_height, local_height)
if remote_height > (local_height + s3_headers_depth):
return True
return False
def _check_header_file_integrity(self):
# TODO: temporary workaround for usability. move to txlbryum and check headers instead of file integrity
if conf.settings['blockchain_name'] != "lbrycrd_main":
return
hashsum = sha256()
checksum_height, checksum = conf.settings['HEADERS_FILE_SHA256_CHECKSUM']
checksum_length_in_bytes = checksum_height * HEADER_SIZE
if self.local_header_file_size() < checksum_length_in_bytes:
return
with open(self.headers_file, "rb") as headers_file:
hashsum.update(headers_file.read(checksum_length_in_bytes))
current_checksum = hashsum.hexdigest()
if current_checksum != checksum:
msg = f"Expected checksum {checksum}, got {current_checksum}"
log.warning("Wallet file corrupted, checksum mismatch. " + msg)
log.warning("Deleting header file so it can be downloaded again.")
os.unlink(self.headers_file)
elif (self.local_header_file_size() % HEADER_SIZE) != 0:
log.warning("Header file is good up to checkpoint height, but incomplete. Truncating to checkpoint.")
with open(self.headers_file, "rb+") as headers_file:
headers_file.truncate(checksum_length_in_bytes)
async def start(self):
conf.settings.ensure_wallet_dir()
if not os.path.exists(self.headers_dir):
os.mkdir(self.headers_dir)
if os.path.exists(self.old_file):
log.warning("Moving old headers from %s to %s.", self.old_file, self.headers_file)
os.rename(self.old_file, self.headers_file)
self._downloading_headers = await self.should_download_headers_from_s3()
if self._downloading_headers:
try:
await d2f(self.fetch_headers_from_s3())
except Exception as err:
log.error("failed to fetch headers from s3: %s", err)
finally:
self._downloading_headers = False
async def stop(self):
pass
class WalletComponent(Component):
component_name = WALLET_COMPONENT
depends_on = [DATABASE_COMPONENT, HEADERS_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.wallet_manager = None
@property
def component(self):
return self.wallet_manager
async def get_status(self):
if self.wallet_manager and self.running:
local_height = self.wallet_manager.network.get_local_height()
remote_height = self.wallet_manager.network.get_server_height()
best_hash = self.wallet_manager.get_best_blockhash()
return {
'blocks': max(local_height, 0),
'blocks_behind': max(remote_height - local_height, 0),
'best_blockhash': best_hash,
'is_encrypted': self.wallet_manager.wallet.use_encryption,
'is_locked': not self.wallet_manager.is_wallet_unlocked,
}
async def start(self):
conf.settings.ensure_wallet_dir()
log.info("Starting torba wallet")
storage = self.component_manager.get_component(DATABASE_COMPONENT)
lbrynet.schema.BLOCKCHAIN_NAME = conf.settings['blockchain_name']
self.wallet_manager = await LbryWalletManager.from_lbrynet_config(conf.settings, storage)
self.wallet_manager.old_db = storage
await self.wallet_manager.start()
async def stop(self):
await self.wallet_manager.stop()
self.wallet_manager = None
class BlobComponent(Component):
component_name = BLOB_COMPONENT
depends_on = [DATABASE_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.blob_manager = None
@property
def component(self):
return self.blob_manager
def start(self):
storage = self.component_manager.get_component(DATABASE_COMPONENT)
datastore = None
if DHT_COMPONENT not in self.component_manager.skip_components:
dht_node = self.component_manager.get_component(DHT_COMPONENT)
if dht_node:
datastore = dht_node._dataStore
self.blob_manager = DiskBlobManager(os.path.join(conf.settings.data_dir, "blobfiles"), storage, datastore)
return self.blob_manager.setup()
def stop(self):
return self.blob_manager.stop()
async def get_status(self):
count = 0
if self.blob_manager:
count = await self.blob_manager.storage.count_finished_blobs()
return {'finished_blobs': count}
class DHTComponent(Component):
component_name = DHT_COMPONENT
depends_on = [UPNP_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.dht_node = None
self.upnp_component = None
self.external_udp_port = None
self.external_peer_port = None
@property
def component(self):
return self.dht_node
async def get_status(self):
return {
'node_id': binascii.hexlify(conf.settings.get_node_id()),
'peers_in_routing_table': 0 if not self.dht_node else len(self.dht_node.contacts)
}
async def start(self):
self.upnp_component = self.component_manager.get_component(UPNP_COMPONENT)
self.external_peer_port = self.upnp_component.upnp_redirects.get("TCP", conf.settings["peer_port"])
self.external_udp_port = self.upnp_component.upnp_redirects.get("UDP", conf.settings["dht_node_port"])
node_id = conf.settings.get_node_id()
if node_id is None:
node_id = generate_id()
external_ip = self.upnp_component.external_ip
if not external_ip:
log.warning("UPnP component failed to get external ip")
external_ip = await get_external_ip()
if not external_ip:
log.warning("failed to get external ip")
self.dht_node = Node(
node_id=node_id,
udpPort=conf.settings['dht_node_port'],
externalUDPPort=self.external_udp_port,
externalIP=external_ip,
peerPort=self.external_peer_port
)
await d2f(self.dht_node.start(conf.settings['known_dht_nodes'], block_on_join=False))
log.info("Started the dht")
def stop(self):
return d2f(self.dht_node.stop())
class HashAnnouncerComponent(Component):
component_name = HASH_ANNOUNCER_COMPONENT
depends_on = [DHT_COMPONENT, DATABASE_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.hash_announcer = None
@property
def component(self):
return self.hash_announcer
async def start(self):
storage = self.component_manager.get_component(DATABASE_COMPONENT)
dht_node = self.component_manager.get_component(DHT_COMPONENT)
self.hash_announcer = DHTHashAnnouncer(dht_node, storage)
self.hash_announcer.start()
def stop(self):
self.hash_announcer.stop()
async def get_status(self):
return {
'announce_queue_size': 0 if not self.hash_announcer else len(self.hash_announcer.hash_queue)
}
class RateLimiterComponent(Component):
component_name = RATE_LIMITER_COMPONENT
def __init__(self, component_manager):
super().__init__(component_manager)
self.rate_limiter = RateLimiter()
@property
def component(self):
return self.rate_limiter
async def start(self):
self.rate_limiter.start()
async def stop(self):
self.rate_limiter.stop()
class PaymentRateComponent(Component):
component_name = PAYMENT_RATE_COMPONENT
def __init__(self, component_manager):
super().__init__(component_manager)
self.payment_rate_manager = OnlyFreePaymentsManager()
@property
def component(self):
return self.payment_rate_manager
async def start(self):
pass
async def stop(self):
pass
class FileManagerComponent(Component):
component_name = FILE_MANAGER_COMPONENT
depends_on = [RATE_LIMITER_COMPONENT, BLOB_COMPONENT, DATABASE_COMPONENT, WALLET_COMPONENT,
PAYMENT_RATE_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.file_manager = None
@property
def component(self):
return self.file_manager
async def get_status(self):
if not self.file_manager:
return
return {
'managed_files': len(self.file_manager.lbry_files)
}
def start(self):
rate_limiter = self.component_manager.get_component(RATE_LIMITER_COMPONENT)
blob_manager = self.component_manager.get_component(BLOB_COMPONENT)
storage = self.component_manager.get_component(DATABASE_COMPONENT)
wallet = self.component_manager.get_component(WALLET_COMPONENT)
sd_identifier = StreamDescriptorIdentifier()
add_lbry_file_to_sd_identifier(sd_identifier)
file_saver_factory = EncryptedFileSaverFactory(
self.component_manager.peer_finder,
rate_limiter,
blob_manager,
storage,
wallet,
conf.settings.download_dir
)
sd_identifier.add_stream_downloader_factory(EncryptedFileStreamType, file_saver_factory)
payment_rate_manager = self.component_manager.get_component(PAYMENT_RATE_COMPONENT)
log.info('Starting the file manager')
self.file_manager = EncryptedFileManager(self.component_manager.peer_finder, rate_limiter, blob_manager, wallet,
payment_rate_manager, storage, sd_identifier)
return self.file_manager.setup()
def stop(self):
return d2f(self.file_manager.stop())
class PeerProtocolServerComponent(Component):
component_name = PEER_PROTOCOL_SERVER_COMPONENT
depends_on = [UPNP_COMPONENT, RATE_LIMITER_COMPONENT, BLOB_COMPONENT, WALLET_COMPONENT,
PAYMENT_RATE_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.lbry_server_port = None
@property
def component(self):
return self.lbry_server_port
async def start(self):
wallet = self.component_manager.get_component(WALLET_COMPONENT)
upnp = self.component_manager.get_component(UPNP_COMPONENT)
peer_port = conf.settings['peer_port']
query_handlers = {
handler.get_primary_query_identifier(): handler for handler in [
BlobRequestHandlerFactory(
self.component_manager.get_component(BLOB_COMPONENT),
wallet,
self.component_manager.get_component(PAYMENT_RATE_COMPONENT),
self.component_manager.analytics_manager
),
wallet.get_wallet_info_query_handler_factory(),
]
}
server_factory = ServerProtocolFactory(
self.component_manager.get_component(RATE_LIMITER_COMPONENT), query_handlers,
self.component_manager.peer_manager
)
try:
log.info("Peer protocol listening on TCP %i (ext port %i)", peer_port,
upnp.upnp_redirects.get("TCP", peer_port))
self.lbry_server_port = reactor.listenTCP(peer_port, server_factory)
except error.CannotListenError as e:
import traceback
log.error("Couldn't bind to port %d. Visit lbry.io/faq/how-to-change-port for"
" more details.", peer_port)
log.error("%s", traceback.format_exc())
raise ValueError("%s lbrynet may already be running on your computer." % str(e))
async def stop(self):
if self.lbry_server_port is not None:
self.lbry_server_port, old_port = None, self.lbry_server_port
log.info('Stop listening on port %s', old_port.port)
await d2f(old_port.stopListening())
class ReflectorComponent(Component):
component_name = REFLECTOR_COMPONENT
depends_on = [BLOB_COMPONENT, FILE_MANAGER_COMPONENT]
def __init__(self, component_manager):
super().__init__(component_manager)
self.reflector_server_port = conf.settings['reflector_port']
self.reflector_server = None
@property
def component(self):
return self.reflector_server
async def start(self):
log.info("Starting reflector server")
blob_manager = self.component_manager.get_component(BLOB_COMPONENT)
file_manager = self.component_manager.get_component(FILE_MANAGER_COMPONENT)
reflector_factory = ReflectorServerFactory(self.component_manager.peer_manager, blob_manager, file_manager)
try:
self.reflector_server = await d2f(reactor.listenTCP(self.reflector_server_port, reflector_factory))
log.info('Started reflector on port %s', self.reflector_server_port)
except error.CannotListenError as e:
log.exception("Couldn't bind reflector to port %d", self.reflector_server_port)
raise ValueError(f"{e} lbrynet may already be running on your computer.")
async def stop(self):
if self.reflector_server is not None:
log.info("Stopping reflector server")
self.reflector_server, p = None, self.reflector_server
await d2f(p.stopListening())
class UPnPComponent(Component):
component_name = UPNP_COMPONENT
def __init__(self, component_manager):
super().__init__(component_manager)
self._int_peer_port = conf.settings['peer_port']
self._int_dht_node_port = conf.settings['dht_node_port']
self.use_upnp = conf.settings['use_upnp']
self.upnp = None
self.upnp_redirects = {}
self.external_ip = None
self._maintain_redirects_task = None
@property
def component(self):
return self
async def _repeatedly_maintain_redirects(self, now=True):
while True:
if now:
await self._maintain_redirects()
await asyncio.sleep(360)
async def _maintain_redirects(self):
# setup the gateway if necessary
if not self.upnp:
try:
self.upnp = await UPnP.discover()
log.info("found upnp gateway: %s", self.upnp.gateway.manufacturer_string)
except Exception as err:
log.warning("upnp discovery failed: %s", err)
self.upnp = None
# update the external ip
external_ip = None
if self.upnp:
try:
external_ip = await self.upnp.get_external_ip()
if external_ip != "0.0.0.0" and not self.external_ip:
log.info("got external ip from UPnP: %s", external_ip)
except (asyncio.TimeoutError, UPnPError):
pass
if external_ip == "0.0.0.0" or not external_ip:
log.warning("unable to get external ip from UPnP, checking lbry.io fallback")
external_ip = await get_external_ip()
if self.external_ip and self.external_ip != external_ip:
log.info("external ip changed from %s to %s", self.external_ip, external_ip)
self.external_ip = external_ip
assert self.external_ip is not None # TODO: handle going/starting offline
if not self.upnp_redirects and self.upnp: # setup missing redirects
try:
log.info("add UPnP port mappings")
d = {}
if PEER_PROTOCOL_SERVER_COMPONENT not in self.component_manager.skip_components:
d["TCP"] = self.upnp.get_next_mapping(self._int_peer_port, "TCP", "LBRY peer port")
if DHT_COMPONENT not in self.component_manager.skip_components:
d["UDP"] = self.upnp.get_next_mapping(self._int_dht_node_port, "UDP", "LBRY DHT port")
upnp_redirects = await gather_dict(d)
log.info("set up redirects: %s", upnp_redirects)
self.upnp_redirects.update(upnp_redirects)
except (asyncio.TimeoutError, UPnPError):
self.upnp = None
return self._maintain_redirects()
elif self.upnp: # check existing redirects are still active
found = set()
mappings = await self.upnp.get_redirects()
for mapping in mappings:
proto = mapping['NewProtocol']
if proto in self.upnp_redirects and mapping['NewExternalPort'] == self.upnp_redirects[proto]:
if mapping['NewInternalClient'] == self.upnp.lan_address:
found.add(proto)
if 'UDP' not in found and DHT_COMPONENT not in self.component_manager.skip_components:
try:
udp_port = await self.upnp.get_next_mapping(self._int_dht_node_port, "UDP", "LBRY DHT port")
self.upnp_redirects['UDP'] = udp_port
log.info("refreshed upnp redirect for dht port: %i", udp_port)
except (asyncio.TimeoutError, UPnPError):
del self.upnp_redirects['UDP']
if 'TCP' not in found and PEER_PROTOCOL_SERVER_COMPONENT not in self.component_manager.skip_components:
try:
tcp_port = await self.upnp.get_next_mapping(self._int_peer_port, "TCP", "LBRY peer port")
self.upnp_redirects['TCP'] = tcp_port
log.info("refreshed upnp redirect for peer port: %i", tcp_port)
except (asyncio.TimeoutError, UPnPError):
del self.upnp_redirects['TCP']
if ('TCP' in self.upnp_redirects
and PEER_PROTOCOL_SERVER_COMPONENT not in self.component_manager.skip_components) and (
'UDP' in self.upnp_redirects and DHT_COMPONENT not in self.component_manager.skip_components):
if self.upnp_redirects:
log.debug("upnp redirects are still active")
async def start(self):
log.info("detecting external ip")
if not self.use_upnp:
self.external_ip = await get_external_ip()
return
success = False
await self._maintain_redirects()
if self.upnp:
if not self.upnp_redirects and not all([x in self.component_manager.skip_components for x in
(DHT_COMPONENT, PEER_PROTOCOL_SERVER_COMPONENT)]):
log.error("failed to setup upnp, debugging infomation: %s", self.upnp.zipped_debugging_info)
else:
success = True
if self.upnp_redirects:
log.debug("set up upnp port redirects for gateway: %s", self.upnp.gateway.manufacturer_string)
else:
log.error("failed to setup upnp")
self.component_manager.analytics_manager.send_upnp_setup_success_fail(success, await self.get_status())
self._maintain_redirects_task = asyncio.create_task(self._repeatedly_maintain_redirects(now=False))
async def stop(self):
if self.upnp_redirects:
await asyncio.wait([
self.upnp.delete_port_mapping(port, protocol) for protocol, port in self.upnp_redirects.items()
])
if self._maintain_redirects_task is not None and not self._maintain_redirects_task.done():
self._maintain_redirects_task.cancel()
async def get_status(self):
return {
'aioupnp_version': aioupnp_version,
'redirects': self.upnp_redirects,
'gateway': 'No gateway found' if not self.upnp else self.upnp.gateway.manufacturer_string,
'dht_redirect_set': 'UDP' in self.upnp_redirects,
'peer_redirect_set': 'TCP' in self.upnp_redirects,
'external_ip': self.external_ip
}
class ExchangeRateManagerComponent(Component):
component_name = EXCHANGE_RATE_MANAGER_COMPONENT
def __init__(self, component_manager):
Component.__init__(self, component_manager)
self.exchange_rate_manager = ExchangeRateManager()
@property
def component(self):
return self.exchange_rate_manager
async def start(self):
self.exchange_rate_manager.start()
async def stop(self):
self.exchange_rate_manager.stop()