lbry-sdk/lbrynet/p2p/client/StandaloneBlobDownloader.py
2018-11-09 16:52:46 -05:00

143 lines
5.4 KiB
Python

import logging
from lbrynet.p2p.BlobInfo import BlobInfo
from lbrynet.p2p.client.BlobRequester import BlobRequester
from lbrynet.p2p.client.ConnectionManager import ConnectionManager
from lbrynet.p2p.client.DownloadManager import DownloadManager
from lbrynet.p2p.Error import InvalidBlobHashError, DownloadSDTimeout
from lbrynet.blob.blob_file import is_valid_blobhash
from lbrynet.utils import safe_start_looping_call, safe_stop_looping_call
from twisted.python.failure import Failure
from twisted.internet import defer
from twisted.internet.task import LoopingCall
log = logging.getLogger(__name__)
class SingleBlobMetadataHandler:
#implements(interfaces.IMetadataHandler)
def __init__(self, blob_hash, download_manager):
self.blob_hash = blob_hash
self.download_manager = download_manager
######## IMetadataHandler #########
def get_initial_blobs(self):
log.debug("Returning the blob info")
return defer.succeed([BlobInfo(self.blob_hash, 0, None)])
def final_blob_num(self):
return 0
class SingleProgressManager:
def __init__(self, download_manager, finished_callback, timeout_callback, timeout):
self.finished_callback = finished_callback
self.timeout_callback = timeout_callback
self.download_manager = download_manager
self.timeout = timeout
self.timeout_counter = 0
self.checker = LoopingCall(self._check_if_finished)
def start(self):
safe_start_looping_call(self.checker, 1)
return defer.succeed(True)
def stop(self):
safe_stop_looping_call(self.checker)
return defer.succeed(True)
def _check_if_finished(self):
if self.stream_position() == 1:
blob_downloaded = self.download_manager.blobs[0]
log.debug("The blob %s has been downloaded. Calling the finished callback",
str(blob_downloaded))
safe_stop_looping_call(self.checker)
self.finished_callback(blob_downloaded)
elif self.timeout is not None:
self.timeout_counter += 1
if self.timeout_counter >= self.timeout:
safe_stop_looping_call(self.checker)
self.timeout_callback()
def stream_position(self):
blobs = self.download_manager.blobs
if blobs and blobs[0].get_is_verified():
return 1
return 0
def needed_blobs(self):
blobs = self.download_manager.blobs
assert len(blobs) == 1
return [b for b in blobs.values() if not b.get_is_verified()]
class DummyBlobHandler:
def __init__(self):
pass
def handle_blob(self, blob, blob_info):
pass
class StandaloneBlobDownloader:
def __init__(self, blob_hash, blob_manager, peer_finder,
rate_limiter, payment_rate_manager, wallet,
timeout=None):
self.blob_hash = blob_hash
self.blob_manager = blob_manager
self.peer_finder = peer_finder
self.rate_limiter = rate_limiter
self.payment_rate_manager = payment_rate_manager
self.wallet = wallet
self.timeout = timeout
self.download_manager = None
self.finished_deferred = None
def download(self):
if not is_valid_blobhash(self.blob_hash):
return defer.fail(Failure(InvalidBlobHashError(self.blob_hash)))
def cancel_download(d):
self.stop()
self.finished_deferred = defer.Deferred(canceller=cancel_download)
self.download_manager = DownloadManager(self.blob_manager)
self.download_manager.blob_requester = BlobRequester(self.blob_manager, self.peer_finder,
self.payment_rate_manager, self.wallet,
self.download_manager)
self.download_manager.blob_info_finder = SingleBlobMetadataHandler(self.blob_hash,
self.download_manager)
self.download_manager.progress_manager = SingleProgressManager(self.download_manager,
self._blob_downloaded,
self._download_timedout,
self.timeout)
self.download_manager.blob_handler = DummyBlobHandler()
self.download_manager.wallet_info_exchanger = self.wallet.get_info_exchanger()
self.download_manager.connection_manager = ConnectionManager(
self, self.rate_limiter,
[self.download_manager.blob_requester],
[self.download_manager.wallet_info_exchanger]
)
d = self.download_manager.start_downloading()
d.addCallback(lambda _: self.finished_deferred)
return d
def stop(self):
return self.download_manager.stop_downloading()
def _blob_downloaded(self, blob):
self.stop()
if not self.finished_deferred.called:
self.finished_deferred.callback(blob)
def _download_timedout(self):
self.stop()
if not self.finished_deferred.called:
self.finished_deferred.errback(DownloadSDTimeout(self.blob_hash))
def insufficient_funds(self, err):
self.stop()
if not self.finished_deferred.called:
self.finished_deferred.errback(err)