Mercurial > hg
view mercurial/httpclient/_readers.py @ 35011:a2dfc723b6b5
bundle: allow bundlerepo to support alternative manifest implementations
With our treemanifest logic, the manifests are no longer transported as part of
the changegroup and are no longer stored in a revlog. This means the
self.manifestlog line in bundlerepo.filestart no longer calls
_constructmanifest, and therefore does not consume the manifest portion of the
changegroup, which means filestart is not populated and we result in an infinite
loop.
The fix is to make filestart aware that self.manifestlog might not consume the
changegroup part, and consume it manually if necessary.
There's currently no way to test this in core, but our treemanifest extension
has tests to cover this.
Differential Revision: https://phab.mercurial-scm.org/D1329
author | Durham Goode <durham@fb.com> |
---|---|
date | Tue, 07 Nov 2017 10:16:53 -0800 |
parents | 456609cbd840 |
children |
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# Copyright 2011, Google Inc. # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """Reader objects to abstract out different body response types. This module is package-private. It is not expected that these will have any clients outside of httpplus. """ from __future__ import absolute_import try: import httplib httplib.HTTPException except ImportError: import http.client as httplib import logging logger = logging.getLogger(__name__) class ReadNotReady(Exception): """Raised when read() is attempted but not enough data is loaded.""" class HTTPRemoteClosedError(httplib.HTTPException): """The server closed the remote socket in the middle of a response.""" class AbstractReader(object): """Abstract base class for response readers. Subclasses must implement _load, and should implement _close if it's not an error for the server to close their socket without some termination condition being detected during _load. """ def __init__(self): self._finished = False self._done_chunks = [] self.available_data = 0 def _addchunk(self, data): self._done_chunks.append(data) self.available_data += len(data) def _pushchunk(self, data): self._done_chunks.insert(0, data) self.available_data += len(data) def _popchunk(self): b = self._done_chunks.pop(0) self.available_data -= len(b) return b def done(self): """Returns true if the response body is entirely read.""" return self._finished def read(self, amt): """Read amt bytes from the response body.""" if self.available_data < amt and not self._finished: raise ReadNotReady() blocks = [] need = amt while self._done_chunks: b = self._popchunk() if len(b) > need: nb = b[:need] self._pushchunk(b[need:]) b = nb blocks.append(b) need -= len(b) if need == 0: break result = b''.join(blocks) assert len(result) == amt or (self._finished and len(result) < amt) return result def readto(self, delimstr, blocks = None): """return available data chunks up to the first one in which delimstr occurs. No data will be returned after delimstr -- the chunk in which it occurs will be split and the remainder pushed back onto the available data queue. If blocks is supplied chunks will be added to blocks, otherwise a new list will be allocated. """ if blocks is None: blocks = [] while self._done_chunks: b = self._popchunk() i = b.find(delimstr) + len(delimstr) if i: if i < len(b): self._pushchunk(b[i:]) blocks.append(b[:i]) break else: blocks.append(b) return blocks def _load(self, data): # pragma: no cover """Subclasses must implement this. As data is available to be read out of this object, it should be placed into the _done_chunks list. Subclasses should not rely on data remaining in _done_chunks forever, as it may be reaped if the client is parsing data as it comes in. """ raise NotImplementedError def _close(self): """Default implementation of close. The default implementation assumes that the reader will mark the response as finished on the _finished attribute once the entire response body has been read. In the event that this is not true, the subclass should override the implementation of close (for example, close-is-end responses have to set self._finished in the close handler.) """ if not self._finished: raise HTTPRemoteClosedError( 'server appears to have closed the socket mid-response') class AbstractSimpleReader(AbstractReader): """Abstract base class for simple readers that require no response decoding. Examples of such responses are Connection: Close (close-is-end) and responses that specify a content length. """ def _load(self, data): if data: assert not self._finished, ( 'tried to add data (%r) to a closed reader!' % data) logger.debug('%s read an additional %d data', self.name, len(data)) # pylint: disable=E1101 self._addchunk(data) class CloseIsEndReader(AbstractSimpleReader): """Reader for responses that specify Connection: Close for length.""" name = 'close-is-end' def _close(self): logger.info('Marking close-is-end reader as closed.') self._finished = True class ContentLengthReader(AbstractSimpleReader): """Reader for responses that specify an exact content length.""" name = 'content-length' def __init__(self, amount): AbstractSimpleReader.__init__(self) self._amount = amount if amount == 0: self._finished = True self._amount_seen = 0 def _load(self, data): AbstractSimpleReader._load(self, data) self._amount_seen += len(data) if self._amount_seen >= self._amount: self._finished = True logger.debug('content-length read complete') class ChunkedReader(AbstractReader): """Reader for chunked transfer encoding responses.""" def __init__(self, eol): AbstractReader.__init__(self) self._eol = eol self._leftover_skip_amt = 0 self._leftover_data = '' def _load(self, data): assert not self._finished, 'tried to add data to a closed reader!' logger.debug('chunked read an additional %d data', len(data)) position = 0 if self._leftover_data: logger.debug( 'chunked reader trying to finish block from leftover data') # TODO: avoid this string concatenation if possible data = self._leftover_data + data position = self._leftover_skip_amt self._leftover_data = '' self._leftover_skip_amt = 0 datalen = len(data) while position < datalen: split = data.find(self._eol, position) if split == -1: self._leftover_data = data self._leftover_skip_amt = position return amt = int(data[position:split], base=16) block_start = split + len(self._eol) # If the whole data chunk plus the eol trailer hasn't # loaded, we'll wait for the next load. if block_start + amt + len(self._eol) > len(data): self._leftover_data = data self._leftover_skip_amt = position return if amt == 0: self._finished = True logger.debug('closing chunked reader due to chunk of length 0') return self._addchunk(data[block_start:block_start + amt]) position = block_start + amt + len(self._eol) # no-check-code