lbry-sdk/lbrynet/core/client/StandaloneBlobDownloader.py
2018-08-24 11:37:53 -04:00

142 lines
5.4 KiB
Python

import logging
from lbrynet.core.BlobInfo import BlobInfo
from lbrynet.core.client.BlobRequester import BlobRequester
from lbrynet.core.client.ConnectionManager import ConnectionManager
from lbrynet.core.client.DownloadManager import DownloadManager
from lbrynet.core.Error import InvalidBlobHashError, DownloadSDTimeout
from lbrynet.core.utils import is_valid_blobhash, 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(object):
#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(object):
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(object):
def __init__(self):
pass
def handle_blob(self, blob, blob_info):
pass
class StandaloneBlobDownloader(object):
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)