--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/bundlecaches.py Thu Oct 15 15:57:36 2020 +0200
@@ -0,0 +1,422 @@
+# bundlecaches.py - utility to deal with pre-computed bundle for servers
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+from .i18n import _
+
+from .thirdparty import attr
+
+from . import (
+ error,
+ sslutil,
+ util,
+)
+from .utils import stringutil
+
+urlreq = util.urlreq
+
+
+@attr.s
+class bundlespec(object):
+ compression = attr.ib()
+ wirecompression = attr.ib()
+ version = attr.ib()
+ wireversion = attr.ib()
+ params = attr.ib()
+ contentopts = attr.ib()
+
+
+# Maps bundle version human names to changegroup versions.
+_bundlespeccgversions = {
+ b'v1': b'01',
+ b'v2': b'02',
+ b'packed1': b's1',
+ b'bundle2': b'02', # legacy
+}
+
+# Maps bundle version with content opts to choose which part to bundle
+_bundlespeccontentopts = {
+ b'v1': {
+ b'changegroup': True,
+ b'cg.version': b'01',
+ b'obsolescence': False,
+ b'phases': False,
+ b'tagsfnodescache': False,
+ b'revbranchcache': False,
+ },
+ b'v2': {
+ b'changegroup': True,
+ b'cg.version': b'02',
+ b'obsolescence': False,
+ b'phases': False,
+ b'tagsfnodescache': True,
+ b'revbranchcache': True,
+ },
+ b'packed1': {b'cg.version': b's1'},
+}
+_bundlespeccontentopts[b'bundle2'] = _bundlespeccontentopts[b'v2']
+
+_bundlespecvariants = {
+ b"streamv2": {
+ b"changegroup": False,
+ b"streamv2": True,
+ b"tagsfnodescache": False,
+ b"revbranchcache": False,
+ }
+}
+
+# Compression engines allowed in version 1. THIS SHOULD NEVER CHANGE.
+_bundlespecv1compengines = {b'gzip', b'bzip2', b'none'}
+
+
+def parsebundlespec(repo, spec, strict=True):
+ """Parse a bundle string specification into parts.
+
+ Bundle specifications denote a well-defined bundle/exchange format.
+ The content of a given specification should not change over time in
+ order to ensure that bundles produced by a newer version of Mercurial are
+ readable from an older version.
+
+ The string currently has the form:
+
+ <compression>-<type>[;<parameter0>[;<parameter1>]]
+
+ Where <compression> is one of the supported compression formats
+ and <type> is (currently) a version string. A ";" can follow the type and
+ all text afterwards is interpreted as URI encoded, ";" delimited key=value
+ pairs.
+
+ If ``strict`` is True (the default) <compression> is required. Otherwise,
+ it is optional.
+
+ Returns a bundlespec object of (compression, version, parameters).
+ Compression will be ``None`` if not in strict mode and a compression isn't
+ defined.
+
+ An ``InvalidBundleSpecification`` is raised when the specification is
+ not syntactically well formed.
+
+ An ``UnsupportedBundleSpecification`` is raised when the compression or
+ bundle type/version is not recognized.
+
+ Note: this function will likely eventually return a more complex data
+ structure, including bundle2 part information.
+ """
+
+ def parseparams(s):
+ if b';' not in s:
+ return s, {}
+
+ params = {}
+ version, paramstr = s.split(b';', 1)
+
+ for p in paramstr.split(b';'):
+ if b'=' not in p:
+ raise error.InvalidBundleSpecification(
+ _(
+ b'invalid bundle specification: '
+ b'missing "=" in parameter: %s'
+ )
+ % p
+ )
+
+ key, value = p.split(b'=', 1)
+ key = urlreq.unquote(key)
+ value = urlreq.unquote(value)
+ params[key] = value
+
+ return version, params
+
+ if strict and b'-' not in spec:
+ raise error.InvalidBundleSpecification(
+ _(
+ b'invalid bundle specification; '
+ b'must be prefixed with compression: %s'
+ )
+ % spec
+ )
+
+ if b'-' in spec:
+ compression, version = spec.split(b'-', 1)
+
+ if compression not in util.compengines.supportedbundlenames:
+ raise error.UnsupportedBundleSpecification(
+ _(b'%s compression is not supported') % compression
+ )
+
+ version, params = parseparams(version)
+
+ if version not in _bundlespeccgversions:
+ raise error.UnsupportedBundleSpecification(
+ _(b'%s is not a recognized bundle version') % version
+ )
+ else:
+ # Value could be just the compression or just the version, in which
+ # case some defaults are assumed (but only when not in strict mode).
+ assert not strict
+
+ spec, params = parseparams(spec)
+
+ if spec in util.compengines.supportedbundlenames:
+ compression = spec
+ version = b'v1'
+ # Generaldelta repos require v2.
+ if b'generaldelta' in repo.requirements:
+ version = b'v2'
+ # Modern compression engines require v2.
+ if compression not in _bundlespecv1compengines:
+ version = b'v2'
+ elif spec in _bundlespeccgversions:
+ if spec == b'packed1':
+ compression = b'none'
+ else:
+ compression = b'bzip2'
+ version = spec
+ else:
+ raise error.UnsupportedBundleSpecification(
+ _(b'%s is not a recognized bundle specification') % spec
+ )
+
+ # Bundle version 1 only supports a known set of compression engines.
+ if version == b'v1' and compression not in _bundlespecv1compengines:
+ raise error.UnsupportedBundleSpecification(
+ _(b'compression engine %s is not supported on v1 bundles')
+ % compression
+ )
+
+ # The specification for packed1 can optionally declare the data formats
+ # required to apply it. If we see this metadata, compare against what the
+ # repo supports and error if the bundle isn't compatible.
+ if version == b'packed1' and b'requirements' in params:
+ requirements = set(params[b'requirements'].split(b','))
+ missingreqs = requirements - repo.supportedformats
+ if missingreqs:
+ raise error.UnsupportedBundleSpecification(
+ _(b'missing support for repository features: %s')
+ % b', '.join(sorted(missingreqs))
+ )
+
+ # Compute contentopts based on the version
+ contentopts = _bundlespeccontentopts.get(version, {}).copy()
+
+ # Process the variants
+ if b"stream" in params and params[b"stream"] == b"v2":
+ variant = _bundlespecvariants[b"streamv2"]
+ contentopts.update(variant)
+
+ engine = util.compengines.forbundlename(compression)
+ compression, wirecompression = engine.bundletype()
+ wireversion = _bundlespeccgversions[version]
+
+ return bundlespec(
+ compression, wirecompression, version, wireversion, params, contentopts
+ )
+
+
+def parseclonebundlesmanifest(repo, s):
+ """Parses the raw text of a clone bundles manifest.
+
+ Returns a list of dicts. The dicts have a ``URL`` key corresponding
+ to the URL and other keys are the attributes for the entry.
+ """
+ m = []
+ for line in s.splitlines():
+ fields = line.split()
+ if not fields:
+ continue
+ attrs = {b'URL': fields[0]}
+ for rawattr in fields[1:]:
+ key, value = rawattr.split(b'=', 1)
+ key = util.urlreq.unquote(key)
+ value = util.urlreq.unquote(value)
+ attrs[key] = value
+
+ # Parse BUNDLESPEC into components. This makes client-side
+ # preferences easier to specify since you can prefer a single
+ # component of the BUNDLESPEC.
+ if key == b'BUNDLESPEC':
+ try:
+ bundlespec = parsebundlespec(repo, value)
+ attrs[b'COMPRESSION'] = bundlespec.compression
+ attrs[b'VERSION'] = bundlespec.version
+ except error.InvalidBundleSpecification:
+ pass
+ except error.UnsupportedBundleSpecification:
+ pass
+
+ m.append(attrs)
+
+ return m
+
+
+def isstreamclonespec(bundlespec):
+ # Stream clone v1
+ if bundlespec.wirecompression == b'UN' and bundlespec.wireversion == b's1':
+ return True
+
+ # Stream clone v2
+ if (
+ bundlespec.wirecompression == b'UN'
+ and bundlespec.wireversion == b'02'
+ and bundlespec.contentopts.get(b'streamv2')
+ ):
+ return True
+
+ return False
+
+
+def filterclonebundleentries(repo, entries, streamclonerequested=False):
+ """Remove incompatible clone bundle manifest entries.
+
+ Accepts a list of entries parsed with ``parseclonebundlesmanifest``
+ and returns a new list consisting of only the entries that this client
+ should be able to apply.
+
+ There is no guarantee we'll be able to apply all returned entries because
+ the metadata we use to filter on may be missing or wrong.
+ """
+ newentries = []
+ for entry in entries:
+ spec = entry.get(b'BUNDLESPEC')
+ if spec:
+ try:
+ bundlespec = parsebundlespec(repo, spec, strict=True)
+
+ # If a stream clone was requested, filter out non-streamclone
+ # entries.
+ if streamclonerequested and not isstreamclonespec(bundlespec):
+ repo.ui.debug(
+ b'filtering %s because not a stream clone\n'
+ % entry[b'URL']
+ )
+ continue
+
+ except error.InvalidBundleSpecification as e:
+ repo.ui.debug(stringutil.forcebytestr(e) + b'\n')
+ continue
+ except error.UnsupportedBundleSpecification as e:
+ repo.ui.debug(
+ b'filtering %s because unsupported bundle '
+ b'spec: %s\n' % (entry[b'URL'], stringutil.forcebytestr(e))
+ )
+ continue
+ # If we don't have a spec and requested a stream clone, we don't know
+ # what the entry is so don't attempt to apply it.
+ elif streamclonerequested:
+ repo.ui.debug(
+ b'filtering %s because cannot determine if a stream '
+ b'clone bundle\n' % entry[b'URL']
+ )
+ continue
+
+ if b'REQUIRESNI' in entry and not sslutil.hassni:
+ repo.ui.debug(
+ b'filtering %s because SNI not supported\n' % entry[b'URL']
+ )
+ continue
+
+ if b'REQUIREDRAM' in entry:
+ try:
+ requiredram = util.sizetoint(entry[b'REQUIREDRAM'])
+ except error.ParseError:
+ repo.ui.debug(
+ b'filtering %s due to a bad REQUIREDRAM attribute\n'
+ % entry[b'URL']
+ )
+ continue
+ actualram = repo.ui.estimatememory()
+ if actualram is not None and actualram * 0.66 < requiredram:
+ repo.ui.debug(
+ b'filtering %s as it needs more than 2/3 of system memory\n'
+ % entry[b'URL']
+ )
+ continue
+
+ newentries.append(entry)
+
+ return newentries
+
+
+class clonebundleentry(object):
+ """Represents an item in a clone bundles manifest.
+
+ This rich class is needed to support sorting since sorted() in Python 3
+ doesn't support ``cmp`` and our comparison is complex enough that ``key=``
+ won't work.
+ """
+
+ def __init__(self, value, prefers):
+ self.value = value
+ self.prefers = prefers
+
+ def _cmp(self, other):
+ for prefkey, prefvalue in self.prefers:
+ avalue = self.value.get(prefkey)
+ bvalue = other.value.get(prefkey)
+
+ # Special case for b missing attribute and a matches exactly.
+ if avalue is not None and bvalue is None and avalue == prefvalue:
+ return -1
+
+ # Special case for a missing attribute and b matches exactly.
+ if bvalue is not None and avalue is None and bvalue == prefvalue:
+ return 1
+
+ # We can't compare unless attribute present on both.
+ if avalue is None or bvalue is None:
+ continue
+
+ # Same values should fall back to next attribute.
+ if avalue == bvalue:
+ continue
+
+ # Exact matches come first.
+ if avalue == prefvalue:
+ return -1
+ if bvalue == prefvalue:
+ return 1
+
+ # Fall back to next attribute.
+ continue
+
+ # If we got here we couldn't sort by attributes and prefers. Fall
+ # back to index order.
+ return 0
+
+ def __lt__(self, other):
+ return self._cmp(other) < 0
+
+ def __gt__(self, other):
+ return self._cmp(other) > 0
+
+ def __eq__(self, other):
+ return self._cmp(other) == 0
+
+ def __le__(self, other):
+ return self._cmp(other) <= 0
+
+ def __ge__(self, other):
+ return self._cmp(other) >= 0
+
+ def __ne__(self, other):
+ return self._cmp(other) != 0
+
+
+def sortclonebundleentries(ui, entries):
+ prefers = ui.configlist(b'ui', b'clonebundleprefers')
+ if not prefers:
+ return list(entries)
+
+ def _split(p):
+ if b'=' not in p:
+ hint = _(b"each comma separated item should be key=value pairs")
+ raise error.Abort(
+ _(b"invalid ui.clonebundleprefers item: %s") % p, hint=hint
+ )
+ return p.split(b'=', 1)
+
+ prefers = [_split(p) for p in prefers]
+
+ items = sorted(clonebundleentry(v, prefers) for v in entries)
+ return [i.value for i in items]