mercurial/filelog.py
author Gregory Szorc <gregory.szorc@gmail.com>
Wed, 26 Sep 2018 18:08:08 -0700
changeset 40026 7e807b8a9e56
parent 40007 1470183068b8
child 40056 324b4b10351e
permissions -rw-r--r--
wireprotov2: client support for following content redirects And with the server actually sending content redirects, it is finally time to implement client support for following them! When a redirect response is seen, we wait until all data for that request has been received (it should be nearly immediate since no data is expected to follow the redirect message). Then we use a URL opener to make a request. We stuff that response into the client handler and construct a new response object to track it. When readdata() is called for servicing requests, we attempt to read data from the first redirected response. During data reading, data is processed similarly to as if it came from a frame payload. The existing test for the functionality demonstrates the client transparently following the redirect and obtaining the command response data from an alternate URL! There is still plenty of work to do here, including shoring up testing. I'm not convinced things will work in the presence of multiple redirect responses. And we don't yet implement support for integrity verification or configuring server certificates to validate the connection. But it's a start. And it should enable us to start experimenting with "real" caches. Differential Revision: https://phab.mercurial-scm.org/D4778

# filelog.py - file history class for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from . import (
    error,
    repository,
    revlog,
)
from .utils import (
    interfaceutil,
    storageutil,
)

@interfaceutil.implementer(repository.ifilestorage)
class filelog(object):
    def __init__(self, opener, path):
        self._revlog = revlog.revlog(opener,
                                     '/'.join(('data', path + '.i')),
                                     censorable=True)
        # Full name of the user visible file, relative to the repository root.
        # Used by LFS.
        self._revlog.filename = path

    def __len__(self):
        return len(self._revlog)

    def __iter__(self):
        return self._revlog.__iter__()

    def revs(self, start=0, stop=None):
        return self._revlog.revs(start=start, stop=stop)

    def parents(self, node):
        return self._revlog.parents(node)

    def parentrevs(self, rev):
        return self._revlog.parentrevs(rev)

    def rev(self, node):
        return self._revlog.rev(node)

    def node(self, rev):
        return self._revlog.node(rev)

    def lookup(self, node):
        return storageutil.fileidlookup(self._revlog, node,
                                        self._revlog.indexfile)

    def linkrev(self, rev):
        return self._revlog.linkrev(rev)

    def commonancestorsheads(self, node1, node2):
        return self._revlog.commonancestorsheads(node1, node2)

    # Used by dagop.blockdescendants().
    def descendants(self, revs):
        return self._revlog.descendants(revs)

    def heads(self, start=None, stop=None):
        return self._revlog.heads(start, stop)

    # Used by hgweb, children extension.
    def children(self, node):
        return self._revlog.children(node)

    def iscensored(self, rev):
        return self._revlog.iscensored(rev)

    def revision(self, node, _df=None, raw=False):
        return self._revlog.revision(node, _df=_df, raw=raw)

    def emitrevisions(self, nodes, nodesorder=None,
                      revisiondata=False, assumehaveparentrevisions=False,
                      deltaprevious=False):
        return self._revlog.emitrevisions(
            nodes, nodesorder=nodesorder, revisiondata=revisiondata,
            assumehaveparentrevisions=assumehaveparentrevisions,
            deltaprevious=deltaprevious)

    def addrevision(self, revisiondata, transaction, linkrev, p1, p2,
                    node=None, flags=revlog.REVIDX_DEFAULT_FLAGS,
                    cachedelta=None):
        return self._revlog.addrevision(revisiondata, transaction, linkrev,
                                    p1, p2, node=node, flags=flags,
                                    cachedelta=cachedelta)

    def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
        return self._revlog.addgroup(deltas, linkmapper, transaction,
                                 addrevisioncb=addrevisioncb)

    def getstrippoint(self, minlink):
        return self._revlog.getstrippoint(minlink)

    def strip(self, minlink, transaction):
        return self._revlog.strip(minlink, transaction)

    def censorrevision(self, tr, node, tombstone=b''):
        return self._revlog.censorrevision(node, tombstone=tombstone)

    def files(self):
        return self._revlog.files()

    def read(self, node):
        return storageutil.filtermetadata(self.revision(node))

    def add(self, text, meta, transaction, link, p1=None, p2=None):
        if meta or text.startswith('\1\n'):
            text = storageutil.packmeta(meta, text)
        return self.addrevision(text, transaction, link, p1, p2)

    def renamed(self, node):
        return storageutil.filerevisioncopied(self, node)

    def size(self, rev):
        """return the size of a given revision"""

        # for revisions with renames, we have to go the slow way
        node = self.node(rev)
        if self.renamed(node):
            return len(self.read(node))
        if self.iscensored(rev):
            return 0

        # XXX if self.read(node).startswith("\1\n"), this returns (size+4)
        return self._revlog.size(rev)

    def cmp(self, node, text):
        """compare text with a given file revision

        returns True if text is different than what is stored.
        """
        return not storageutil.filedataequivalent(self, node, text)

    def verifyintegrity(self, state):
        return self._revlog.verifyintegrity(state)

    def storageinfo(self, exclusivefiles=False, sharedfiles=False,
                    revisionscount=False, trackedsize=False,
                    storedsize=False):
        return self._revlog.storageinfo(
            exclusivefiles=exclusivefiles, sharedfiles=sharedfiles,
            revisionscount=revisionscount, trackedsize=trackedsize,
            storedsize=storedsize)

    # TODO these aren't part of the interface and aren't internal methods.
    # Callers should be fixed to not use them.

    # Used by bundlefilelog, unionfilelog.
    @property
    def indexfile(self):
        return self._revlog.indexfile

    @indexfile.setter
    def indexfile(self, value):
        self._revlog.indexfile = value

    # Used by repo upgrade.
    def clone(self, tr, destrevlog, **kwargs):
        if not isinstance(destrevlog, filelog):
            raise error.ProgrammingError('expected filelog to clone()')

        return self._revlog.clone(tr, destrevlog._revlog, **kwargs)

class narrowfilelog(filelog):
    """Filelog variation to be used with narrow stores."""

    def __init__(self, opener, path, narrowmatch):
        super(narrowfilelog, self).__init__(opener, path)
        self._narrowmatch = narrowmatch

    def renamed(self, node):
        res = super(narrowfilelog, self).renamed(node)

        # Renames that come from outside the narrowspec are problematic
        # because we may lack the base text for the rename. This can result
        # in code attempting to walk the ancestry or compute a diff
        # encountering a missing revision. We address this by silently
        # removing rename metadata if the source file is outside the
        # narrow spec.
        #
        # A better solution would be to see if the base revision is available,
        # rather than assuming it isn't.
        #
        # An even better solution would be to teach all consumers of rename
        # metadata that the base revision may not be available.
        #
        # TODO consider better ways of doing this.
        if res and not self._narrowmatch(res[0]):
            return None

        return res

    def size(self, rev):
        # Because we have a custom renamed() that may lie, we need to call
        # the base renamed() to report accurate results.
        node = self.node(rev)
        if super(narrowfilelog, self).renamed(node):
            return len(self.read(node))
        else:
            return super(narrowfilelog, self).size(rev)

    def cmp(self, node, text):
        different = super(narrowfilelog, self).cmp(node, text)

        # Because renamed() may lie, we may get false positives for
        # different content. Check for this by comparing against the original
        # renamed() implementation.
        if different:
            if super(narrowfilelog, self).renamed(node):
                t2 = self.read(node)
                return t2 != text

        return different