from twisted.web2.http import Response, splitHostPort
from HTTPDownloader import Peer
+from Streams import GrowingFileStream, StreamToFile
from util import uncompact
from Hash import PIECE_SIZE
from apt_p2p_Khashmir.bencode import bdecode
from apt_p2p_conf import config
-class GrowingFileStream(stream.FileStream):
- """Modified to stream data from a file as it becomes available.
-
- @ivar CHUNK_SIZE: the maximum size of chunks of data to send at a time
- @ivar deferred: waiting for the result of the last read attempt
- @ivar available: the number of bytes that are currently available to read
- @ivar position: the current position in the file where the next read will begin
- @ivar finished: True when no more data will be coming available
- """
-
- CHUNK_SIZE = 4*1024
-
- def __init__(self, f, length = None):
- stream.FileStream.__init__(self, f)
- self.length = length
- self.deferred = None
- self.available = 0L
- self.position = 0L
- self.finished = False
-
- def updateAvailable(self, newlyAvailable):
- """Update the number of bytes that are available.
-
- Call it with 0 to trigger reading of a fully read file.
-
- @param newlyAvailable: the number of bytes that just became available
- """
- assert not self.finished
- self.available += newlyAvailable
-
- # If a read is pending, let it go
- if self.deferred and self.position < self.available:
- # Try to read some data from the file
- length = self.available - self.position
- readSize = min(length, self.CHUNK_SIZE)
- self.f.seek(self.position)
- b = self.f.read(readSize)
- bytesRead = len(b)
-
- # Check if end of file was reached
- if bytesRead:
- self.position += bytesRead
- deferred = self.deferred
- self.deferred = None
- deferred.callback(b)
-
- def allAvailable(self):
- """Indicate that no more data will be coming available."""
- self.finished = True
-
- # If a read is pending, let it go
- if self.deferred:
- if self.position < self.available:
- # Try to read some data from the file
- length = self.available - self.position
- readSize = min(length, self.CHUNK_SIZE)
- self.f.seek(self.position)
- b = self.f.read(readSize)
- bytesRead = len(b)
-
- # Check if end of file was reached
- if bytesRead:
- self.position += bytesRead
- deferred = self.deferred
- self.deferred = None
- deferred.callback(b)
- else:
- # We're done
- deferred = self.deferred
- self.deferred = None
- deferred.callback(None)
- else:
- # We're done
- deferred = self.deferred
- self.deferred = None
- deferred.callback(None)
-
- def read(self, sendfile=False):
- assert not self.deferred, "A previous read is still deferred."
-
- if self.f is None:
- return None
-
- length = self.available - self.position
- readSize = min(length, self.CHUNK_SIZE)
-
- # If we don't have any available, we're done or deferred
- if readSize <= 0:
- if self.finished:
- return None
- else:
- self.deferred = defer.Deferred()
- return self.deferred
-
- # Try to read some data from the file
- self.f.seek(self.position)
- b = self.f.read(readSize)
- bytesRead = len(b)
- if not bytesRead:
- # End of file was reached, we're done or deferred
- if self.finished:
- return None
- else:
- self.deferred = defer.Deferred()
- return self.deferred
- else:
- self.position += bytesRead
- return b
-
-class StreamToFile:
- """Save a stream to a partial file and hash it.
-
- @type stream: L{twisted.web2.stream.IByteStream}
- @ivar stream: the input stream being read
- @type outFile: L{twisted.python.filepath.FilePath}
- @ivar outFile: the file being written
- @type hash: C{sha1}
- @ivar hash: the hash object for the data
- @type position: C{int}
- @ivar position: the current file position to write the next data to
- @type length: C{int}
- @ivar length: the position in the file to not write beyond
- @type inform: C{method}
- @ivar inform: a function to call with the length of data received
- @type doneDefer: L{twisted.internet.defer.Deferred}
- @ivar doneDefer: the deferred that will fire when done writing
- """
-
- def __init__(self, inputStream, outFile, start = 0, length = None, inform = None):
- """Initializes the file.
-
- @type inputStream: L{twisted.web2.stream.IByteStream}
- @param inputStream: the input stream to read from
- @type outFile: L{twisted.python.filepath.FilePath}
- @param outFile: the file to write to
- @type start: C{int}
- @param start: the file position to start writing at
- (optional, defaults to the start of the file)
- @type length: C{int}
- @param length: the maximum amount of data to write to the file
- (optional, defaults to not limiting the writing to the file
- @type inform: C{method}
- @param inform: a function to call with the length of data received
- (optional, defaults to calling nothing)
- """
- self.stream = inputStream
- self.outFile = outFile
- self.hash = sha.new()
- self.position = start
- self.length = None
- if length is not None:
- self.length = start + length
- self.inform = inform
- self.doneDefer = None
-
- def run(self):
- """Start the streaming.
-
- @rtype: L{twisted.internet.defer.Deferred}
- """
- log.msg('Started streaming %r bytes to file at position %d' % (self.length, self.position))
- self.doneDefer = stream.readStream(self.stream, self._gotData)
- self.doneDefer.addCallbacks(self._done, self._error)
- return self.doneDefer
-
- def _gotData(self, data):
- """Process the received data."""
- if self.outFile.closed:
- raise Exception, "outFile was unexpectedly closed"
-
- if data is None:
- raise Exception, "Data is None?"
-
- # Make sure we don't go too far
- if self.length is not None and self.position + len(data) > self.length:
- data = data[:(self.length - self.position)]
-
- # Write and hash the streamed data
- self.outFile.seek(self.position)
- self.outFile.write(data)
- self.hash.update(data)
- self.position += len(data)
- self.inform(len(data))
-
- def _done(self, result):
- """Return the result."""
- log.msg('Streaming is complete')
- return self.hash.digest()
-
- def _error(self, err):
- """Log the error."""
- log.msg('Streaming error')
- log.err(err)
- return err
+class PeerError(Exception):
+ """An error occurred downloading from peers."""
class FileDownload:
"""Manage a download from a list of peers or a mirror.
self.compact_peers = compact_peers
self.path = '/~/' + quote_plus(hash.expected())
+ self.defer = None
self.mirror_path = None
self.pieces = None
self.started = False
# del self.peers[site]
# Start the DHT lookup
- lookupDefer = self.manager.dht.getValue(key)
+ lookupDefer = self.manager.dht.get(key)
lookupDefer.addBoth(self._getDHTPieces, key)
def _getDHTPieces(self, results, key):
if self.pieces is None:
# Send a request to one or more peers
- log.msg('Checking for a peer to request piece hashes from')
for site in self.peers:
if self.peers[site].get('failed', False) != True:
log.msg('Sending a piece hash request to %r' % (site, ))
if self.outstanding >= 4:
break
- log.msg('Done sending piece hash requests for now, %d outstanding' % self.outstanding)
if self.pieces is None and self.outstanding <= 0:
# Continue without the piece hashes
log.msg('Could not retrieve the piece hashes from the peers')
log.msg('Got a piece hash response %d from %r' % (response.code, site))
if response.code != 200:
# Request failed, try a different peer
- log.msg('Did not like response %d from %r' % (response.code, site))
self.getPeerPieces(key, site)
else:
# Read the response stream to a string
if parsed[0] == "http":
site = splitHostPort(parsed[0], parsed[1])
self.mirror_path = urlunparse(('', '') + parsed[2:])
- peer = self.manager.getPeer(site)
- peer.mirror = True
+ peer = self.manager.getPeer(site, mirror = True)
self.peerlist.append(peer)
# Special case if there's only one good peer left
# self.defer.callback(self.peerlist[0].get(self.path))
# return
- # Start sending the return file
- self.stream = GrowingFileStream(self.file, self.hash.expSize)
- resp = Response(200, {}, self.stream)
- self.defer.callback(resp)
-
# Begin to download the pieces
self.outstanding = 0
self.nextFinish = 0
#{ Downloading the pieces
def getPieces(self):
"""Download the next pieces from the peers."""
- log.msg('Checking for more piece requests to send')
+ if self.file.closed:
+ log.msg('Download has been aborted for %s' % self.path)
+ self.stream.allAvailable(remove = True)
+ return
+
self.sort()
piece = self.nextFinish
while self.outstanding < 4 and self.peerlist and piece < len(self.completePieces):
- log.msg('Checking piece %d' % piece)
if self.completePieces[piece] == False:
# Send a request to the highest ranked peer
peer = self.peerlist.pop()
log.msg('Sending a request for piece %d to peer %r' % (piece, peer))
self.outstanding += 1
+ path = self.path
if peer.mirror:
- df = peer.getRange(self.mirror_path, piece*PIECE_SIZE, (piece+1)*PIECE_SIZE - 1)
+ path = self.mirror_path
+ if len(self.completePieces) > 1:
+ df = peer.getRange(path, piece*PIECE_SIZE, (piece+1)*PIECE_SIZE - 1)
else:
- df = peer.getRange(self.path, piece*PIECE_SIZE, (piece+1)*PIECE_SIZE - 1)
+ df = peer.get(path)
reactor.callLater(0, df.addCallbacks,
*(self._getPiece, self._getError),
**{'callbackArgs': (piece, peer),
'errbackArgs': (piece, peer)})
piece += 1
- log.msg('Finished checking pieces, %d outstanding, next piece %d of %d' % (self.outstanding, self.nextFinish, len(self.completePieces)))
# Check if we're done
if self.outstanding <= 0 and self.nextFinish >= len(self.completePieces):
- log.msg('We seem to be done with all pieces')
- self.stream.allAvailable()
+ log.msg('Download is complete for %s' % self.path)
+ self.stream.allAvailable(remove = True)
def _getPiece(self, response, piece, peer):
"""Process the retrieved headers from the peer."""
- log.msg('Got response for piece %d from peer %r' % (piece, peer))
if ((len(self.completePieces) > 1 and response.code != 206) or
(response.code not in (200, 206))):
# Request failed, try a different peer
if response.stream and response.stream.length:
stream.readAndDiscard(response.stream)
else:
+ if self.defer:
+ # Start sending the return file
+ df = self.defer
+ self.defer = None
+ self.stream = GrowingFileStream(self.file, self.hash.expSize)
+
+ # Get the headers from the peer's response
+ headers = {}
+ if response.headers.hasHeader('last-modified'):
+ headers['last-modified'] = response.headers.getHeader('last-modified')
+ resp = Response(200, headers, self.stream)
+ df.callback(resp)
+
# Read the response stream to the file
log.msg('Streaming piece %d from peer %r' % (piece, peer))
- def statUpdate(bytes, stats = self.manager.stats, mirror = peer.mirror):
- stats.receivedBytes(bytes, mirror)
if response.code == 206:
- df = StreamToFile(response.stream, self.file, piece*PIECE_SIZE,
- PIECE_SIZE, statUpdate).run()
+ df = StreamToFile(self.hash.newPieceHasher(), response.stream,
+ self.file, piece*PIECE_SIZE, PIECE_SIZE).run()
else:
- df = StreamToFile(response.stream, self.file,
- inform = statUpdate).run()
+ df = StreamToFile(self.hash.newHasher(), response.stream,
+ self.file).run()
reactor.callLater(0, df.addCallbacks,
*(self._gotPiece, self._gotError),
**{'callbackArgs': (piece, peer),
self.getPieces()
log.err(err)
- def _gotPiece(self, response, piece, peer):
+ def _gotPiece(self, hash, piece, peer):
"""Process the retrieved piece from the peer."""
- log.msg('Finished streaming piece %d from peer %r: %r' % (piece, peer, response))
- if self.pieces[piece] and response != self.pieces[piece]:
+ if self.pieces[piece] and hash.digest() != self.pieces[piece]:
# Hash doesn't match
log.msg('Hash error for piece %d from peer %r' % (piece, peer))
peer.hashError('Piece received from peer does not match expected')
def _gotError(self, err, piece, peer):
"""Piece download failed, try again."""
- log.msg('Error streaming piece %d from peer %r: %r' % (piece, peer, response))
+ log.msg('Error streaming piece %d from peer %r: %r' % (piece, peer, err))
log.err(err)
self.completePieces[piece] = False
self.getPieces()
@type cache_dir: L{twisted.python.filepath.FilePath}
@ivar cache_dir: the directory to use for storing all files
- @type dht: L{interfaces.IDHT}
+ @type dht: L{DHTManager.DHT}
@ivar dht: the DHT instance
@type stats: L{stats.StatsLogger}
@ivar stats: the statistics logger to record sent data to
assert parsed[0] == "http", "Only HTTP is supported, not '%s'" % parsed[0]
site = splitHostPort(parsed[0], parsed[1])
path = urlunparse(('', '') + parsed[2:])
- peer = self.getPeer(site)
- peer.mirror = True
+ peer = self.getPeer(site, mirror = True)
return peer.get(path, method, modtime)
# elif len(peers) == 1:
# site = uncompact(peers[0]['c'])
tmpfile = self.cache_dir.child(hash.hexexpected())
return FileDownload(self, hash, mirror, peers, tmpfile).run()
- def getPeer(self, site):
+ def getPeer(self, site, mirror = False):
"""Create a new peer if necessary and return it.
@type site: (C{string}, C{int})
@param site: the IP address and port of the peer
+ @param mirror: whether the peer is actually a mirror
+ (optional, defaults to False)
"""
if site not in self.clients:
- self.clients[site] = Peer(site[0], site[1])
+ self.clients[site] = Peer(site[0], site[1], self.stats)
+ if mirror:
+ self.clients[site].mirror = True
return self.clients[site]
def close(self):
projects / quix0rs-apt-p2p.git / blobdiff