ExternalVendorCode/tahoe-lafs
1
0
Fork 0
mirror of https://github.com/tahoe-lafs/tahoe-lafs.git synced 2025-01-18 18:56:28 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

rearrange Retrieve: first step, shouldn't change order of execution

Browse Source
This commit is contained in:
Brian Warner 2011-09-03 20:21:18 -07:00
parent 6b97e6f407
commit 1597aafea1
1 changed files with 31 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

69
src/allmydata/mutable/retrieve.py
View File

@ -222,11 +222,38 @@ class Retrieve:
self._consumer.registerProducer(self, streaming=True)
self._done_deferred = defer.Deferred()
self._offset = offset
self._read_length = size
self._setup_download()
self._setup_encoding_parameters()
self.log("starting download")
self._started_fetching = time.time()
d = self._add_active_peers()
# ...
# The download process beyond this is a state machine.
# _add_active_peers will select the peers that we want to use
# for the download, and then attempt to start downloading. After
# each segment, it will check for doneness, reacting to broken
# peers and corrupt shares as necessary. If it runs out of good
# peers before downloading all of the segments, _done_deferred
# will errback. Otherwise, it will eventually callback with the
# contents of the mutable file.
return self._done_deferred
def _setup_download(self):
self._started = time.time()
self._status.set_status("Retrieving Shares")
self._offset = offset
self._read_length = size
# how many shares do we need?
(seqnum,
root_hash,
IV,
segsize,
datalength,
k,
N,
prefix,
offsets_tuple) = self.verinfo
# first, which servers can we use?
versionmap = self.servermap.make_versionmap()
@ -248,7 +275,7 @@ class Retrieve:
any_cache)
reader.peerid = peerid
self.readers[shnum] = reader
assert len(self.remaining_sharemap) >= k
self.shares = {} # maps shnum to validated blocks
self._active_readers = [] # list of active readers for this dl.
@ -256,46 +283,12 @@ class Retrieve:
# validated the prefix of
self._block_hash_trees = {} # shnum => hashtree
# how many shares do we need?
(seqnum,
root_hash,
IV,
segsize,
datalength,
k,
N,
prefix,
offsets_tuple) = self.verinfo
# We need one share hash tree for the entire file; its leaves
# are the roots of the block hash trees for the shares that
# comprise it, and its root is in the verinfo.
self.share_hash_tree = hashtree.IncompleteHashTree(N)
self.share_hash_tree.set_hashes({0: root_hash})
# This will set up both the segment decoder and the tail segment
# decoder, as well as a variety of other instance variables that
# the download process will use.
self._setup_encoding_parameters()
assert len(self.remaining_sharemap) >= k
self.log("starting download")
self._started_fetching = time.time()
self._add_active_peers()
# The download process beyond this is a state machine.
# _add_active_peers will select the peers that we want to use
# for the download, and then attempt to start downloading. After
# each segment, it will check for doneness, reacting to broken
# peers and corrupt shares as necessary. If it runs out of good
# peers before downloading all of the segments, _done_deferred
# will errback. Otherwise, it will eventually callback with the
# contents of the mutable file.
return self._done_deferred
def decode(self, blocks_and_salts, segnum):
"""
I am a helper method that the mutable file update process uses
@ -322,7 +315,7 @@ class Retrieve:
def _setup_encoding_parameters(self):
"""
I set up the encoding parameters, including k, n, the number
of segments associated with this file, and the segment decoder.
of segments associated with this file, and the segment decoders.
"""
(seqnum,
root_hash,