lbry-sdk/lbrynet/core/client/DownloadManager.py
2016-12-30 13:27:16 -06:00

124 lines
4.2 KiB
Python

import logging
from twisted.internet import defer
from twisted.python import failure
from zope.interface import implements
from lbrynet import interfaces
log = logging.getLogger(__name__)
class DownloadManager(object):
implements(interfaces.IDownloadManager)
def __init__(self, blob_manager, upload_allowed):
self.blob_manager = blob_manager
self.upload_allowed = upload_allowed
self.blob_info_finder = None
self.progress_manager = None
self.blob_handler = None
self.connection_manager = None
self.blobs = {}
self.blob_infos = {}
######### IDownloadManager #########
def start_downloading(self):
d = self.blob_info_finder.get_initial_blobs()
log.debug("Requested the initial blobs from the info finder")
d.addCallback(self.add_blobs_to_download)
d.addCallback(lambda _: self.resume_downloading())
return d
def resume_downloading(self):
def check_start(result, manager):
if isinstance(result, failure.Failure):
log.error("Failed to start the %s: %s", manager, result.getErrorMessage())
return False
return True
d1 = self.progress_manager.start()
d1.addBoth(check_start, "progress manager")
d2 = self.connection_manager.start()
d2.addBoth(check_start, "connection manager")
dl = defer.DeferredList([d1, d2])
dl.addCallback(lambda xs: False not in xs)
return dl
def stop_downloading(self):
def check_stop(result, manager):
if isinstance(result, failure.Failure):
log.error("Failed to stop the %s: %s", manager, result.getErrorMessage())
return False
return True
d1 = self.progress_manager.stop()
d1.addBoth(check_stop, "progress manager")
d2 = self.connection_manager.stop()
d2.addBoth(check_stop, "connection manager")
dl = defer.DeferredList([d1, d2])
dl.addCallback(lambda xs: False not in xs)
return dl
def add_blobs_to_download(self, blob_infos):
log.debug("Adding %s blobs to blobs", len(blob_infos))
def add_blob_to_list(blob, blob_num):
self.blobs[blob_num] = blob
log.debug(
"Added blob (hash: %s, number %s) to the list", blob.blob_hash, blob_num)
def error_during_add(err):
log.warning(
"An error occurred adding the blob to blobs. Error:%s", err.getErrorMessage())
return err
ds = []
for blob_info in blob_infos:
if not blob_info.blob_num in self.blobs:
self.blob_infos[blob_info.blob_num] = blob_info
log.debug(
"Trying to get the blob associated with blob hash %s", blob_info.blob_hash)
d = self.blob_manager.get_blob(
blob_info.blob_hash, self.upload_allowed, blob_info.length)
d.addCallback(add_blob_to_list, blob_info.blob_num)
d.addErrback(error_during_add)
ds.append(d)
dl = defer.DeferredList(ds)
return dl
def stream_position(self):
return self.progress_manager.stream_position()
def needed_blobs(self):
return self.progress_manager.needed_blobs()
def final_blob_num(self):
return self.blob_info_finder.final_blob_num()
def handle_blob(self, blob_num):
return self.blob_handler.handle_blob(self.blobs[blob_num], self.blob_infos[blob_num])
def calculate_total_bytes(self):
return sum([bi.length for bi in self.blob_infos.itervalues()])
def calculate_bytes_left_to_output(self):
if not self.blobs:
return self.calculate_total_bytes()
else:
to_be_outputted = [
b for n, b in self.blobs.iteritems()
if n >= self.progress_manager.last_blob_outputted
]
return sum([b.length for b in to_be_outputted if b.length is not None])
def calculate_bytes_left_to_download(self):
if not self.blobs:
return self.calculate_total_bytes()
else:
return sum([b.length for b in self.needed_blobs() if b.length is not None])