lbry-sdk/lbrynet/lbrynet_daemon/Downloader.py
2017-06-02 11:52:51 -04:00

206 lines
8.1 KiB
Python

import logging
import os
from twisted.internet import defer, threads
from twisted.internet.task import LoopingCall
from lbryschema.fee import Fee
from lbrynet.core.Error import InsufficientFundsError, KeyFeeAboveMaxAllowed
from lbrynet.core.StreamDescriptor import download_sd_blob
from lbrynet.lbryfilemanager.EncryptedFileDownloader import ManagedEncryptedFileDownloaderFactory
from lbrynet import conf
INITIALIZING_CODE = 'initializing'
DOWNLOAD_METADATA_CODE = 'downloading_metadata'
DOWNLOAD_TIMEOUT_CODE = 'timeout'
DOWNLOAD_RUNNING_CODE = 'running'
DOWNLOAD_STOPPED_CODE = 'stopped'
STREAM_STAGES = [
(INITIALIZING_CODE, 'Initializing'),
(DOWNLOAD_METADATA_CODE, 'Downloading metadata'),
(DOWNLOAD_RUNNING_CODE, 'Started stream'),
(DOWNLOAD_STOPPED_CODE, 'Paused stream'),
(DOWNLOAD_TIMEOUT_CODE, 'Stream timed out')
]
log = logging.getLogger(__name__)
def safe_start(looping_call):
if not looping_call.running:
looping_call.start(1)
def safe_stop(looping_call):
if looping_call.running:
looping_call.stop()
class GetStream(object):
def __init__(self, sd_identifier, session, wallet, lbry_file_manager, exchange_rate_manager,
max_key_fee, data_rate=None, timeout=None, download_directory=None,
file_name=None):
self.timeout = timeout or conf.settings['download_timeout']
self.data_rate = data_rate or conf.settings['data_rate']
self.max_key_fee = max_key_fee or conf.settings['max_key_fee'][1]
self.download_directory = download_directory or conf.settings['download_directory']
self.file_name = file_name
self.timeout_counter = 0
self.code = None
self.sd_hash = None
self.wallet = wallet
self.session = session
self.exchange_rate_manager = exchange_rate_manager
self.payment_rate_manager = self.session.payment_rate_manager
self.lbry_file_manager = lbry_file_manager
self.sd_identifier = sd_identifier
self.downloader = None
self.checker = LoopingCall(self.check_status)
# fired when the download is complete
self.finished_deferred = defer.Deferred(None)
# fired after the metadata and the first data blob have been downloaded
self.data_downloading_deferred = defer.Deferred(None)
self._running = False
@property
def download_path(self):
return os.path.join(self.download_directory, self.downloader.file_name)
def _check_status(self, status):
if status.num_completed and not self.data_downloading_deferred.called:
self.data_downloading_deferred.callback(True)
if self.data_downloading_deferred.called:
safe_stop(self.checker)
else:
log.info("Downloading stream data (%i seconds)", self.timeout_counter)
def check_status(self):
"""
Check if we've got the first data blob in the stream yet
"""
self.timeout_counter += 1
if self.timeout_counter >= self.timeout:
if not self.data_downloading_deferred.called:
self.data_downloading_deferred.errback(Exception("Timeout"))
safe_stop(self.checker)
elif self.downloader:
d = self.downloader.status()
d.addCallback(self._check_status)
elif self._running:
log.info("Downloading stream descriptor blob (%i seconds)", self.timeout_counter)
def convert_max_fee(self):
currency, amount = self.max_key_fee['currency'], self.max_key_fee['amount']
return self.exchange_rate_manager.convert_currency(currency, "LBC", amount)
def set_status(self, status, name):
log.info("Download lbry://%s status changed to %s" % (name, status))
self.code = next(s for s in STREAM_STAGES if s[0] == status)
def check_fee_and_convert(self, fee):
max_key_fee_amount = self.convert_max_fee()
converted_fee_amount = self.exchange_rate_manager.convert_currency(fee.currency, "LBC",
fee.amount)
if converted_fee_amount > self.wallet.get_balance():
raise InsufficientFundsError('Unable to pay the key fee of %s' % converted_fee_amount)
if converted_fee_amount > max_key_fee_amount:
raise KeyFeeAboveMaxAllowed('Key fee %s above max allowed %s' % (converted_fee_amount,
max_key_fee_amount))
converted_fee = {
'currency': 'LBC',
'amount': converted_fee_amount,
'address': fee.address
}
return Fee(converted_fee)
def get_downloader_factory(self, factories):
for factory in factories:
if isinstance(factory, ManagedEncryptedFileDownloaderFactory):
return factory
raise Exception('No suitable factory was found in {}'.format(factories))
@defer.inlineCallbacks
def get_downloader(self, factory, stream_metadata):
# TODO: we should use stream_metadata.options.get_downloader_options
# instead of hard-coding the options to be [self.data_rate]
downloader = yield factory.make_downloader(
stream_metadata,
[self.data_rate],
self.payment_rate_manager,
download_directory=self.download_directory,
file_name=self.file_name
)
defer.returnValue(downloader)
def _pay_key_fee(self, address, fee_lbc, name):
log.info("Pay key fee %f --> %s", fee_lbc, address)
reserved_points = self.wallet.reserve_points(address, fee_lbc)
if reserved_points is None:
raise InsufficientFundsError('Unable to pay the key fee of %s for %s' % (fee_lbc, name))
return self.wallet.send_points_to_address(reserved_points, fee_lbc)
@defer.inlineCallbacks
def pay_key_fee(self, fee, name):
if fee is not None:
yield self._pay_key_fee(fee.address, fee.amount, name)
else:
defer.returnValue(None)
@defer.inlineCallbacks
def finish(self, results, name):
self.set_status(DOWNLOAD_STOPPED_CODE, name)
log.info("Finished downloading lbry://%s (%s) --> %s", name, self.sd_hash[:6],
self.download_path)
safe_stop(self.checker)
status = yield self.downloader.status()
self._check_status(status)
defer.returnValue(self.download_path)
@defer.inlineCallbacks
def download(self, stream_info, name):
if self._running:
raise Exception("Already running")
self._running = True
self.set_status(INITIALIZING_CODE, name)
self.sd_hash = stream_info.source_hash
if stream_info.has_fee:
try:
fee = yield threads.deferToThread(self.check_fee_and_convert,
stream_info.source_fee)
except Exception as err:
self._running = False
self.finished_deferred.errback(err)
raise err
else:
fee = None
self.set_status(DOWNLOAD_METADATA_CODE, name)
sd_blob = yield download_sd_blob(self.session, self.sd_hash, self.payment_rate_manager)
stream_metadata = yield self.sd_identifier.get_metadata_for_sd_blob(sd_blob)
factory = self.get_downloader_factory(stream_metadata.factories)
self.downloader = yield self.get_downloader(factory, stream_metadata)
self.set_status(DOWNLOAD_RUNNING_CODE, name)
if fee:
yield self.pay_key_fee(fee, name)
log.info("Downloading lbry://%s (%s) --> %s", name, self.sd_hash[:6], self.download_path)
self.finished_deferred = self.downloader.start()
self.finished_deferred.addCallback(self.finish, name)
@defer.inlineCallbacks
def start(self, stream_info, name):
try:
safe_start(self.checker)
self.download(stream_info, name)
yield self.data_downloading_deferred
defer.returnValue(self.downloader)
except Exception as err:
safe_stop(self.checker)
raise err