From: Brian Warner Date: Sun, 4 Sep 2011 03:21:18 +0000 (-0700) Subject: rearrange Retrieve: first step, shouldn't change order of execution X-Git-Tag: allmydata-tahoe-1.9.0a2~57 X-Git-Url: https://git.rkrishnan.org/junkers?a=commitdiff_plain;h=1597aafea155ede4e23e345171982d8667d8536c;p=tahoe-lafs%2Ftahoe-lafs.git rearrange Retrieve: first step, shouldn't change order of execution --- diff --git a/src/allmydata/mutable/retrieve.py b/src/allmydata/mutable/retrieve.py index f6c99d0f..25930c8e 100644 --- a/src/allmydata/mutable/retrieve.py +++ b/src/allmydata/mutable/retrieve.py @@ -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,