httppeer: detect redirect to URL without query string (issue5860)
197d10e157ce subtly changed the HTTP peer's handling of HTTP redirects.
Before that changeset, we instantiated an HTTP peer instance and
performed the capabilities lookup with that instance. The old code had
the following relevant properties:
1) The HTTP request layer would automatically follow HTTP redirects.
2) An encountered HTTP redirect would update a peer instance variable
pointing to the repo URL.
3) The peer would automagically perform a "capabilities" command
request if a caller requested capabilities but capabilities were
not yet defined.
The first HTTP request issued by a peer is for ?cmd=capabilities. If
the server responds with an HTTP redirect to a ?cmd=capabilities URL,
the HTTP request layer automatically followed it, retrieved a valid
capabilities response, and the peer's base URL was updated
automatically so subsequent requests used the proper URL. In other
words, things "just worked."
In the case where the server redirected to a URL without the
?cmd=capabilities query string, the HTTP request layer would follow
the redirect and likely encounter HTML. The peer's base URL would be
updated and the unexpected Content-Type would raise a RepoError. We
would catch RepoError and immediately call between() (testing the case
for pre 0.9.1 servers not supporting the "capabilities" command). e.g.
try:
inst._fetchcaps()
except error.RepoError:
inst.between([(nullid, nullid)])
between() would eventually call into _callstream(). And _callstream()
made a call to self.capable('httpheader'). capable() would call
self.capabilities(), which would see that no capabilities were set
(because HTML was returned for that request) and call the "capabilities"
command to fetch capabilities. Because the base URL had been updated
from the redirect, this 2nd "capabilities" command would succeed and
the client would immediately call "between," which would also succeed.
The legacy handshake succeeded. Only because "capabilities" was
successfully executed as a side effect did the peer recognize that it
was talking to a modern server. In other words, this all appeared to
work accidentally.
After 197d10e157ce, we stopped calling the "capabilities" command on
the peer instance. Instead, we made the request via a low-level opener,
detected the redirect as part of response handling code, and passed the
redirected URL into the constructed peer instance.
For cases where the redirected URL included the query string, this
"just worked." But for cases where the redirected URL stripped the query
string, we threw RepoError and because we removed the "between" handshake
fallback, we fell through to the "is a static HTTP repo" check and
performed an HTTP request for .hg/requires.
While 197d10e157ce was marked as backwards incompatible, the only
intended backwards incompatible behavior was not performing the
"between" fallback. It was not realized that the "between" command
had the side-effect of recovering from an errant redirect that
dropped the query string.
This commit restores the previous behavior and allows clients to
handle a redirect that drops the query string. In the case where
the request is redirected and the query string is dropped, we raise
a special case of RepoError. We then catch this special exception in
the handshake code and perform another "capabilities" request against
the redirected URL. If that works, all is well. Otherwise, we fall back
to the "is a static HTTP repo" check.
The new code is arguably better than before 197d10e157ce, as it is
explicit about the expected behavior and we avoid performing a
"between" request, saving a server round trip.
Differential Revision: https://phab.mercurial-scm.org/D3433
"""automatically manage newlines in repository files
This extension allows you to manage the type of line endings (CRLF or
LF) that are used in the repository and in the local working
directory. That way you can get CRLF line endings on Windows and LF on
Unix/Mac, thereby letting everybody use their OS native line endings.
The extension reads its configuration from a versioned ``.hgeol``
configuration file found in the root of the working directory. The
``.hgeol`` file use the same syntax as all other Mercurial
configuration files. It uses two sections, ``[patterns]`` and
``[repository]``.
The ``[patterns]`` section specifies how line endings should be
converted between the working directory and the repository. The format is
specified by a file pattern. The first match is used, so put more
specific patterns first. The available line endings are ``LF``,
``CRLF``, and ``BIN``.
Files with the declared format of ``CRLF`` or ``LF`` are always
checked out and stored in the repository in that format and files
declared to be binary (``BIN``) are left unchanged. Additionally,
``native`` is an alias for checking out in the platform's default line
ending: ``LF`` on Unix (including Mac OS X) and ``CRLF`` on
Windows. Note that ``BIN`` (do nothing to line endings) is Mercurial's
default behavior; it is only needed if you need to override a later,
more general pattern.
The optional ``[repository]`` section specifies the line endings to
use for files stored in the repository. It has a single setting,
``native``, which determines the storage line endings for files
declared as ``native`` in the ``[patterns]`` section. It can be set to
``LF`` or ``CRLF``. The default is ``LF``. For example, this means
that on Windows, files configured as ``native`` (``CRLF`` by default)
will be converted to ``LF`` when stored in the repository. Files
declared as ``LF``, ``CRLF``, or ``BIN`` in the ``[patterns]`` section
are always stored as-is in the repository.
Example versioned ``.hgeol`` file::
[patterns]
**.py = native
**.vcproj = CRLF
**.txt = native
Makefile = LF
**.jpg = BIN
[repository]
native = LF
.. note::
The rules will first apply when files are touched in the working
directory, e.g. by updating to null and back to tip to touch all files.
The extension uses an optional ``[eol]`` section read from both the
normal Mercurial configuration files and the ``.hgeol`` file, with the
latter overriding the former. You can use that section to control the
overall behavior. There are three settings:
- ``eol.native`` (default ``os.linesep``) can be set to ``LF`` or
``CRLF`` to override the default interpretation of ``native`` for
checkout. This can be used with :hg:`archive` on Unix, say, to
generate an archive where files have line endings for Windows.
- ``eol.only-consistent`` (default True) can be set to False to make
the extension convert files with inconsistent EOLs. Inconsistent
means that there is both ``CRLF`` and ``LF`` present in the file.
Such files are normally not touched under the assumption that they
have mixed EOLs on purpose.
- ``eol.fix-trailing-newline`` (default False) can be set to True to
ensure that converted files end with a EOL character (either ``\\n``
or ``\\r\\n`` as per the configured patterns).
The extension provides ``cleverencode:`` and ``cleverdecode:`` filters
like the deprecated win32text extension does. This means that you can
disable win32text and enable eol and your filters will still work. You
only need to these filters until you have prepared a ``.hgeol`` file.
The ``win32text.forbid*`` hooks provided by the win32text extension
have been unified into a single hook named ``eol.checkheadshook``. The
hook will lookup the expected line endings from the ``.hgeol`` file,
which means you must migrate to a ``.hgeol`` file first before using
the hook. ``eol.checkheadshook`` only checks heads, intermediate
invalid revisions will be pushed. To forbid them completely, use the
``eol.checkallhook`` hook. These hooks are best used as
``pretxnchangegroup`` hooks.
See :hg:`help patterns` for more information about the glob patterns
used.
"""
from __future__ import absolute_import
import os
import re
from mercurial.i18n import _
from mercurial import (
config,
error as errormod,
extensions,
match,
pycompat,
registrar,
scmutil,
util,
)
from mercurial.utils import (
stringutil,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
configtable = {}
configitem = registrar.configitem(configtable)
configitem('eol', 'fix-trailing-newline',
default=False,
)
configitem('eol', 'native',
default=pycompat.oslinesep,
)
configitem('eol', 'only-consistent',
default=True,
)
# Matches a lone LF, i.e., one that is not part of CRLF.
singlelf = re.compile('(^|[^\r])\n')
def inconsistenteol(data):
return '\r\n' in data and singlelf.search(data)
def tolf(s, params, ui, **kwargs):
"""Filter to convert to LF EOLs."""
if stringutil.binary(s):
return s
if ui.configbool('eol', 'only-consistent') and inconsistenteol(s):
return s
if (ui.configbool('eol', 'fix-trailing-newline')
and s and s[-1] != '\n'):
s = s + '\n'
return util.tolf(s)
def tocrlf(s, params, ui, **kwargs):
"""Filter to convert to CRLF EOLs."""
if stringutil.binary(s):
return s
if ui.configbool('eol', 'only-consistent') and inconsistenteol(s):
return s
if (ui.configbool('eol', 'fix-trailing-newline')
and s and s[-1] != '\n'):
s = s + '\n'
return util.tocrlf(s)
def isbinary(s, params):
"""Filter to do nothing with the file."""
return s
filters = {
'to-lf': tolf,
'to-crlf': tocrlf,
'is-binary': isbinary,
# The following provide backwards compatibility with win32text
'cleverencode:': tolf,
'cleverdecode:': tocrlf
}
class eolfile(object):
def __init__(self, ui, root, data):
self._decode = {'LF': 'to-lf', 'CRLF': 'to-crlf', 'BIN': 'is-binary'}
self._encode = {'LF': 'to-lf', 'CRLF': 'to-crlf', 'BIN': 'is-binary'}
self.cfg = config.config()
# Our files should not be touched. The pattern must be
# inserted first override a '** = native' pattern.
self.cfg.set('patterns', '.hg*', 'BIN', 'eol')
# We can then parse the user's patterns.
self.cfg.parse('.hgeol', data)
isrepolf = self.cfg.get('repository', 'native') != 'CRLF'
self._encode['NATIVE'] = isrepolf and 'to-lf' or 'to-crlf'
iswdlf = ui.config('eol', 'native') in ('LF', '\n')
self._decode['NATIVE'] = iswdlf and 'to-lf' or 'to-crlf'
include = []
exclude = []
self.patterns = []
for pattern, style in self.cfg.items('patterns'):
key = style.upper()
if key == 'BIN':
exclude.append(pattern)
else:
include.append(pattern)
m = match.match(root, '', [pattern])
self.patterns.append((pattern, key, m))
# This will match the files for which we need to care
# about inconsistent newlines.
self.match = match.match(root, '', [], include, exclude)
def copytoui(self, ui):
for pattern, key, m in self.patterns:
try:
ui.setconfig('decode', pattern, self._decode[key], 'eol')
ui.setconfig('encode', pattern, self._encode[key], 'eol')
except KeyError:
ui.warn(_("ignoring unknown EOL style '%s' from %s\n")
% (key, self.cfg.source('patterns', pattern)))
# eol.only-consistent can be specified in ~/.hgrc or .hgeol
for k, v in self.cfg.items('eol'):
ui.setconfig('eol', k, v, 'eol')
def checkrev(self, repo, ctx, files):
failed = []
for f in (files or ctx.files()):
if f not in ctx:
continue
for pattern, key, m in self.patterns:
if not m(f):
continue
target = self._encode[key]
data = ctx[f].data()
if (target == "to-lf" and "\r\n" in data
or target == "to-crlf" and singlelf.search(data)):
failed.append((f, target, bytes(ctx)))
break
return failed
def parseeol(ui, repo, nodes):
try:
for node in nodes:
try:
if node is None:
# Cannot use workingctx.data() since it would load
# and cache the filters before we configure them.
data = repo.wvfs('.hgeol').read()
else:
data = repo[node]['.hgeol'].data()
return eolfile(ui, repo.root, data)
except (IOError, LookupError):
pass
except errormod.ParseError as inst:
ui.warn(_("warning: ignoring .hgeol file due to parse error "
"at %s: %s\n") % (inst.args[1], inst.args[0]))
return None
def ensureenabled(ui):
"""make sure the extension is enabled when used as hook
When eol is used through hooks, the extension is never formally loaded and
enabled. This has some side effect, for example the config declaration is
never loaded. This function ensure the extension is enabled when running
hooks.
"""
if 'eol' in ui._knownconfig:
return
ui.setconfig('extensions', 'eol', '', source='internal')
extensions.loadall(ui, ['eol'])
def _checkhook(ui, repo, node, headsonly):
# Get revisions to check and touched files at the same time
ensureenabled(ui)
files = set()
revs = set()
for rev in xrange(repo[node].rev(), len(repo)):
revs.add(rev)
if headsonly:
ctx = repo[rev]
files.update(ctx.files())
for pctx in ctx.parents():
revs.discard(pctx.rev())
failed = []
for rev in revs:
ctx = repo[rev]
eol = parseeol(ui, repo, [ctx.node()])
if eol:
failed.extend(eol.checkrev(repo, ctx, files))
if failed:
eols = {'to-lf': 'CRLF', 'to-crlf': 'LF'}
msgs = []
for f, target, node in sorted(failed):
msgs.append(_(" %s in %s should not have %s line endings") %
(f, node, eols[target]))
raise errormod.Abort(_("end-of-line check failed:\n") + "\n".join(msgs))
def checkallhook(ui, repo, node, hooktype, **kwargs):
"""verify that files have expected EOLs"""
_checkhook(ui, repo, node, False)
def checkheadshook(ui, repo, node, hooktype, **kwargs):
"""verify that files have expected EOLs"""
_checkhook(ui, repo, node, True)
# "checkheadshook" used to be called "hook"
hook = checkheadshook
def preupdate(ui, repo, hooktype, parent1, parent2):
p1node = scmutil.resolvehexnodeidprefix(repo, parent1)
repo.loadeol([p1node])
return False
def uisetup(ui):
ui.setconfig('hooks', 'preupdate.eol', preupdate, 'eol')
def extsetup(ui):
try:
extensions.find('win32text')
ui.warn(_("the eol extension is incompatible with the "
"win32text extension\n"))
except KeyError:
pass
def reposetup(ui, repo):
uisetup(repo.ui)
if not repo.local():
return
for name, fn in filters.iteritems():
repo.adddatafilter(name, fn)
ui.setconfig('patch', 'eol', 'auto', 'eol')
class eolrepo(repo.__class__):
def loadeol(self, nodes):
eol = parseeol(self.ui, self, nodes)
if eol is None:
return None
eol.copytoui(self.ui)
return eol.match
def _hgcleardirstate(self):
self._eolmatch = self.loadeol([None, 'tip'])
if not self._eolmatch:
self._eolmatch = util.never
return
oldeol = None
try:
cachemtime = os.path.getmtime(self.vfs.join("eol.cache"))
except OSError:
cachemtime = 0
else:
olddata = self.vfs.read("eol.cache")
if olddata:
oldeol = eolfile(self.ui, self.root, olddata)
try:
eolmtime = os.path.getmtime(self.wjoin(".hgeol"))
except OSError:
eolmtime = 0
if eolmtime > cachemtime:
self.ui.debug("eol: detected change in .hgeol\n")
hgeoldata = self.wvfs.read('.hgeol')
neweol = eolfile(self.ui, self.root, hgeoldata)
wlock = None
try:
wlock = self.wlock()
for f in self.dirstate:
if self.dirstate[f] != 'n':
continue
if oldeol is not None:
if not oldeol.match(f) and not neweol.match(f):
continue
oldkey = None
for pattern, key, m in oldeol.patterns:
if m(f):
oldkey = key
break
newkey = None
for pattern, key, m in neweol.patterns:
if m(f):
newkey = key
break
if oldkey == newkey:
continue
# all normal files need to be looked at again since
# the new .hgeol file specify a different filter
self.dirstate.normallookup(f)
# Write the cache to update mtime and cache .hgeol
with self.vfs("eol.cache", "w") as f:
f.write(hgeoldata)
except errormod.LockUnavailable:
# If we cannot lock the repository and clear the
# dirstate, then a commit might not see all files
# as modified. But if we cannot lock the
# repository, then we can also not make a commit,
# so ignore the error.
pass
finally:
if wlock is not None:
wlock.release()
def commitctx(self, ctx, error=False):
for f in sorted(ctx.added() + ctx.modified()):
if not self._eolmatch(f):
continue
fctx = ctx[f]
if fctx is None:
continue
data = fctx.data()
if stringutil.binary(data):
# We should not abort here, since the user should
# be able to say "** = native" to automatically
# have all non-binary files taken care of.
continue
if inconsistenteol(data):
raise errormod.Abort(_("inconsistent newline style "
"in %s\n") % f)
return super(eolrepo, self).commitctx(ctx, error)
repo.__class__ = eolrepo
repo._hgcleardirstate()