view hgext/largefiles/remotestore.py @ 48782:c7dbfc363655

filemerge: when using in-memory merge, always put backup files in temp dir

Before calling a merge tool, we create a backup of the local side of
the merge. That file can be put in the working copy or in a temporary
directory, depending on the user's config. When we're merging in
memory, we don't want to write to the actual, on-disk working copy, so
we write the file to the in-memory working copy instead. However,
since we don't support external merge tools with in-memory merge, it
makes no difference where the file is actually stored (and if we ever
do add support for external merge tools, then the file clearly can't
live in the in-memory working-copy object anyway). So, since it
doesn't matter where the file is stored, we can simplify by always
putting them in the system's temp directory.

Differential Revision: https://phab.mercurial-scm.org/D12187

# Copyright 2010-2011 Fog Creek Software
# Copyright 2010-2011 Unity Technologies
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''remote largefile store; the base class for wirestore'''
from __future__ import absolute_import

from mercurial.i18n import _

from mercurial import (
    error,
    pycompat,
    util,
)

from mercurial.utils import (
    stringutil,
    urlutil,
)

from . import (
    basestore,
    lfutil,
    localstore,
)

urlerr = util.urlerr
urlreq = util.urlreq


class remotestore(basestore.basestore):
    '''a largefile store accessed over a network'''

    def __init__(self, ui, repo, url):
        super(remotestore, self).__init__(ui, repo, url)
        self._lstore = None
        if repo is not None:
            self._lstore = localstore.localstore(self.ui, self.repo, self.repo)

    def put(self, source, hash):
        if self.sendfile(source, hash):
            raise error.Abort(
                _(b'remotestore: could not put %s to remote store %s')
                % (source, urlutil.hidepassword(self.url))
            )
        self.ui.debug(
            _(b'remotestore: put %s to remote store %s\n')
            % (source, urlutil.hidepassword(self.url))
        )

    def exists(self, hashes):
        return {
            h: s == 0
            for (h, s) in pycompat.iteritems(
                self._stat(hashes)
            )  # dict-from-generator
        }

    def sendfile(self, filename, hash):
        self.ui.debug(b'remotestore: sendfile(%s, %s)\n' % (filename, hash))
        try:
            with lfutil.httpsendfile(self.ui, filename) as fd:
                return self._put(hash, fd)
        except IOError as e:
            raise error.Abort(
                _(b'remotestore: could not open file %s: %s')
                % (filename, stringutil.forcebytestr(e))
            )

    def _getfile(self, tmpfile, filename, hash):
        try:
            chunks = self._get(hash)
        except urlerr.httperror as e:
            # 401s get converted to error.Aborts; everything else is fine being
            # turned into a StoreError
            raise basestore.StoreError(
                filename, hash, self.url, stringutil.forcebytestr(e)
            )
        except urlerr.urlerror as e:
            # This usually indicates a connection problem, so don't
            # keep trying with the other files... they will probably
            # all fail too.
            raise error.Abort(
                b'%s: %s' % (urlutil.hidepassword(self.url), e.reason)
            )
        except IOError as e:
            raise basestore.StoreError(
                filename, hash, self.url, stringutil.forcebytestr(e)
            )

        return lfutil.copyandhash(chunks, tmpfile)

    def _hashesavailablelocally(self, hashes):
        existslocallymap = self._lstore.exists(hashes)
        localhashes = [hash for hash in hashes if existslocallymap[hash]]
        return localhashes

    def _verifyfiles(self, contents, filestocheck):
        failed = False
        expectedhashes = [
            expectedhash for cset, filename, expectedhash in filestocheck
        ]
        localhashes = self._hashesavailablelocally(expectedhashes)
        stats = self._stat(
            [
                expectedhash
                for expectedhash in expectedhashes
                if expectedhash not in localhashes
            ]
        )

        for cset, filename, expectedhash in filestocheck:
            if expectedhash in localhashes:
                filetocheck = (cset, filename, expectedhash)
                verifyresult = self._lstore._verifyfiles(
                    contents, [filetocheck]
                )
                if verifyresult:
                    failed = True
            else:
                stat = stats[expectedhash]
                if stat:
                    if stat == 1:
                        self.ui.warn(
                            _(b'changeset %s: %s: contents differ\n')
                            % (cset, filename)
                        )
                        failed = True
                    elif stat == 2:
                        self.ui.warn(
                            _(b'changeset %s: %s missing\n') % (cset, filename)
                        )
                        failed = True
                    else:
                        raise RuntimeError(
                            b'verify failed: unexpected response '
                            b'from statlfile (%r)' % stat
                        )
        return failed

    def _put(self, hash, fd):
        '''Put file with the given hash in the remote store.'''
        raise NotImplementedError(b'abstract method')

    def _get(self, hash):
        '''Get a iterator for content with the given hash.'''
        raise NotImplementedError(b'abstract method')

    def _stat(self, hashes):
        """Get information about availability of files specified by
        hashes in the remote store. Return dictionary mapping hashes
        to return code where 0 means that file is available, other
        values if not."""
        raise NotImplementedError(b'abstract method')