def _report_single_requirement_conflict(
self, req: Requirement,
parent: Optional[Candidate]) -> DistributionNotFound:
if parent is None:
req_disp = str(req)
else:
req_disp = f"{req} (from {parent.name})"
cands = self._finder.find_all_candidates(req.project_name)
versions = [str(v) for v in sorted({c.version for c in cands})]
logger.critical(
"Could not find a version that satisfies the requirement %s "
"(from versions: %s)",
req_disp,
", ".join(versions) or "none",
)
if str(req) == "requirements.txt":
logger.info(
"HINT: You are attempting to install a package literally "
'named "requirements.txt" (which cannot exist). Consider '
"using the '-r' flag to install the packages listed in "
"requirements.txt")
return DistributionNotFound(
f"No matching distribution found for {req}")
def _report_single_requirement_conflict(self, req, parent):
# type: (Requirement, Candidate) -> DistributionNotFound
if parent is None:
req_disp = str(req)
else:
req_disp = f"{req} (from {parent.name})"
logger.critical(
"Could not find a version that satisfies the requirement %s",
req_disp,
)
return DistributionNotFound(
f"No matching distribution found for {req}")
def _report_single_requirement_conflict(self, req, parent):
# type: (Requirement, Optional[Candidate]) -> DistributionNotFound
if parent is None:
req_disp = str(req)
else:
req_disp = f"{req} (from {parent.name})"
cands = self._finder.find_all_candidates(req.project_name)
versions = [str(v) for v in sorted({c.version for c in cands})]
logger.critical(
"Could not find a version that satisfies the requirement %s "
"(from versions: %s)",
req_disp,
", ".join(versions) or "none",
)
return DistributionNotFound(f"No matching distribution found for {req}")
def get_available_package_versions(self, options, args):
# type: (Values, List[Any]) -> None
if len(args) != 1:
raise CommandError('You need to specify exactly one argument')
target_python = cmdoptions.make_target_python(options)
query = args[0]
with self._build_session(options) as session:
finder = self._build_package_finder(
options=options,
session=session,
target_python=target_python,
ignore_requires_python=options.ignore_requires_python,
)
versions: Iterable[Union[LegacyVersion, Version]] = (
candidate.version
for candidate in finder.find_all_candidates(query))
if not options.pre:
# Remove prereleases
versions = (version for version in versions
if not version.is_prerelease)
versions = set(versions)
if not versions:
raise DistributionNotFound(
'No matching distribution found for {}'.format(query))
formatted_versions = [
str(ver) for ver in sorted(versions, reverse=True)
]
latest = formatted_versions[0]
write_output('{} ({})'.format(query, latest))
write_output('Available versions: {}'.format(
', '.join(formatted_versions)))
print_dist_installation_info(query, latest)
def find_requirement(self, req, upgrade):
"""Try to find a Link matching req
Expects req, an InstallRequirement and upgrade, a boolean
Returns a Link if found,
Raises DistributionNotFound or BestVersionAlreadyInstalled otherwise
"""
all_candidates = self.find_all_candidates(req.name)
# Filter out anything which doesn't match our specifier
compatible_versions = set(
req.specifier.filter(
# We turn the version object into a str here because otherwise
# when we're debundled but setuptools isn't, Python will see
# packaging.version.Version and
# pkg_resources._vendor.packaging.version.Version as different
# types. This way we'll use a str as a common data interchange
# format. If we stop using the pkg_resources provided specifier
# and start using our own, we can drop the cast to str().
[str(c.version) for c in all_candidates],
prereleases=(self.allow_all_prereleases
if self.allow_all_prereleases else None),
))
applicable_candidates = [
# Again, converting to str to deal with debundling.
c for c in all_candidates if str(c.version) in compatible_versions
]
if applicable_candidates:
best_candidate = max(applicable_candidates,
key=self._candidate_sort_key)
else:
best_candidate = None
if req.satisfied_by is not None:
installed_version = parse_version(req.satisfied_by.version)
else:
installed_version = None
if installed_version is None and best_candidate is None:
logger.critical(
'Could not find a version that satisfies the requirement %s '
'(from versions: %s)', req, ', '.join(
sorted(
{str(c.version)
for c in all_candidates},
key=parse_version,
)))
raise DistributionNotFound(
'No matching distribution found for %s' % req)
best_installed = False
if installed_version and (best_candidate is None or
best_candidate.version <= installed_version):
best_installed = True
if not upgrade and installed_version is not None:
if best_installed:
logger.debug(
'Existing installed version (%s) is most up-to-date and '
'satisfies requirement',
installed_version,
)
else:
logger.debug(
'Existing installed version (%s) satisfies requirement '
'(most up-to-date version is %s)',
installed_version,
best_candidate.version,
)
return None
if best_installed:
# We have an existing version, and its the best version
logger.debug(
'Installed version (%s) is most up-to-date (past versions: '
'%s)',
installed_version,
', '.join(sorted(compatible_versions, key=parse_version))
or "none",
)
raise BestVersionAlreadyInstalled
logger.debug('Using version %s (newest of versions: %s)',
best_candidate.version,
', '.join(sorted(compatible_versions, key=parse_version)))
return best_candidate.location
def find_requirement(self, req, upgrade):
# type: (InstallRequirement, bool) -> Optional[Link]
"""Try to find a Link matching req
Expects req, an InstallRequirement and upgrade, a boolean
Returns a Link if found,
Raises DistributionNotFound or BestVersionAlreadyInstalled otherwise
"""
candidates = self.find_candidates(req.name, req.specifier)
best_candidate = candidates.get_best()
installed_version = None # type: Optional[_BaseVersion]
if req.satisfied_by is not None:
installed_version = parse_version(req.satisfied_by.version)
def _format_versions(cand_iter):
# This repeated parse_version and str() conversion is needed to
# handle different vendoring sources from pip and pkg_resources.
# If we stop using the pkg_resources provided specifier and start
# using our own, we can drop the cast to str().
return ", ".join(
sorted(
{str(c.version)
for c in cand_iter},
key=parse_version,
)) or "none"
if installed_version is None and best_candidate is None:
logger.critical(
'Could not find a version that satisfies the requirement %s '
'(from versions: %s)',
req,
_format_versions(candidates.iter_all()),
)
raise DistributionNotFound(
'No matching distribution found for %s' % req)
best_installed = False
if installed_version and (best_candidate is None or
best_candidate.version <= installed_version):
best_installed = True
if not upgrade and installed_version is not None:
if best_installed:
logger.debug(
'Existing installed version (%s) is most up-to-date and '
'satisfies requirement',
installed_version,
)
else:
logger.debug(
'Existing installed version (%s) satisfies requirement '
'(most up-to-date version is %s)',
installed_version,
best_candidate.version,
)
return None
if best_installed:
# We have an existing version, and its the best version
logger.debug(
'Installed version (%s) is most up-to-date (past versions: '
'%s)',
installed_version,
_format_versions(candidates.iter_applicable()),
)
raise BestVersionAlreadyInstalled
logger.debug(
'Using version %s (newest of versions: %s)',
best_candidate.version,
_format_versions(candidates.iter_applicable()),
)
return best_candidate.location
def get_installation_error(self, e):
# type: (ResolutionImpossible) -> InstallationError
assert e.causes, "Installation error reported with no cause"
# If one of the things we can't solve is "we need Python X.Y",
# that is what we report.
for cause in e.causes:
if isinstance(cause.requirement, RequiresPythonRequirement):
return self._report_requires_python_error(
cause.requirement,
cause.parent,
)
# Otherwise, we have a set of causes which can't all be satisfied
# at once.
# The simplest case is when we have *one* cause that can't be
# satisfied. We just report that case.
if len(e.causes) == 1:
req, parent = e.causes[0]
if parent is None:
req_disp = str(req)
else:
req_disp = f'{req} (from {parent.name})'
logger.critical(
"Could not find a version that satisfies the requirement %s",
req_disp,
)
return DistributionNotFound(
f'No matching distribution found for {req}')
# OK, we now have a list of requirements that can't all be
# satisfied at once.
# A couple of formatting helpers
def text_join(parts):
# type: (List[str]) -> str
if len(parts) == 1:
return parts[0]
return ", ".join(parts[:-1]) + " and " + parts[-1]
def describe_trigger(parent):
# type: (Candidate) -> str
ireq = parent.get_install_requirement()
if not ireq or not ireq.comes_from:
return f"{parent.name}=={parent.version}"
if isinstance(ireq.comes_from, InstallRequirement):
return str(ireq.comes_from.name)
return str(ireq.comes_from)
triggers = set()
for req, parent in e.causes:
if parent is None:
# This is a root requirement, so we can report it directly
trigger = req.format_for_error()
else:
trigger = describe_trigger(parent)
triggers.add(trigger)
if triggers:
info = text_join(sorted(triggers))
else:
info = "the requested packages"
msg = "Cannot install {} because these package versions " \
"have conflicting dependencies.".format(info)
logger.critical(msg)
msg = "\nThe conflict is caused by:"
for req, parent in e.causes:
msg = msg + "\n "
if parent:
msg = msg + "{} {} depends on ".format(parent.name,
parent.version)
else:
msg = msg + "The user requested "
msg = msg + req.format_for_error()
msg = msg + "\n\n" + \
"To fix this you could try to:\n" + \
"1. loosen the range of package versions you've specified\n" + \
"2. remove package versions to allow pip attempt to solve " + \
"the dependency conflict\n"
logger.info(msg)
return DistributionNotFound("ResolutionImpossible: for help visit "
"https://pip.pypa.io/en/latest/user_guide/"
"#fixing-conflicting-dependencies")
def find_requirement(self, req, upgrade):
# type: (InstallRequirement, bool) -> Optional[Link]
"""Try to find a Link matching req
Expects req, an InstallRequirement and upgrade, a boolean
Returns a Link if found,
Raises DistributionNotFound or BestVersionAlreadyInstalled otherwise
"""
hashes = req.hashes(trust_internet=False)
best_candidate_result = self.find_best_candidate(
req.name,
specifier=req.specifier,
hashes=hashes,
)
best_candidate = best_candidate_result.best_candidate
installed_version = None # type: Optional[_BaseVersion]
if req.satisfied_by is not None:
installed_version = parse_version(req.satisfied_by.version)
def _format_versions(cand_iter):
# type: (Iterable[InstallationCandidate]) -> str
# This repeated parse_version and str() conversion is needed to
# handle different vendoring sources from pip and pkg_resources.
# If we stop using the pkg_resources provided specifier and start
# using our own, we can drop the cast to str().
return (", ".join(
sorted(
{str(c.version)
for c in cand_iter},
key=parse_version,
)) or "none")
if installed_version is None and best_candidate is None:
logger.critical(
"Could not find a version that satisfies the requirement %s "
"(from versions: %s)",
req,
_format_versions(best_candidate_result.iter_all()),
)
raise DistributionNotFound(
"No matching distribution found for {}".format(req))
best_installed = False
if installed_version and (best_candidate is None or
best_candidate.version <= installed_version):
best_installed = True
if not upgrade and installed_version is not None:
if best_installed:
logger.debug(
"Existing installed version (%s) is most up-to-date and "
"satisfies requirement",
installed_version,
)
else:
logger.debug(
"Existing installed version (%s) satisfies requirement "
"(most up-to-date version is %s)",
installed_version,
best_candidate.version,
)
return None
if best_installed:
# We have an existing version, and its the best version
logger.debug(
"Installed version (%s) is most up-to-date (past versions: "
"%s)",
installed_version,
_format_versions(best_candidate_result.iter_applicable()),
)
raise BestVersionAlreadyInstalled
logger.debug(
"Using version %s (newest of versions: %s)",
best_candidate.version,
_format_versions(best_candidate_result.iter_applicable()),
)
return best_candidate.link
def resolve(self, root_reqs, check_supported_wheels):
# type: (List[InstallRequirement], bool) -> RequirementSet
constraints = {} # type: Dict[str, SpecifierSet]
user_requested = set() # type: Set[str]
requirements = []
for req in root_reqs:
if not req.match_markers():
continue
if req.constraint:
# Ensure we only accept valid constraints
reject_invalid_constraint_types(req)
name = canonicalize_name(req.name)
if name in constraints:
constraints[name] = constraints[name] & req.specifier
else:
constraints[name] = req.specifier
else:
if req.is_direct and req.name:
user_requested.add(canonicalize_name(req.name))
requirements.append(
self.factory.make_requirement_from_install_req(req))
provider = PipProvider(
factory=self.factory,
constraints=constraints,
ignore_dependencies=self.ignore_dependencies,
upgrade_strategy=self.upgrade_strategy,
user_requested=user_requested,
)
reporter = BaseReporter()
resolver = RLResolver(provider, reporter)
try:
try_to_avoid_resolution_too_deep = 2000000
self._result = resolver.resolve(
requirements,
max_rounds=try_to_avoid_resolution_too_deep,
)
except ResolutionImpossible as e:
error = self.factory.get_installation_error(e)
if not error:
# TODO: This needs fixing, we need to look at the
# factory.get_installation_error infrastructure, as that
# doesn't really allow for the logger.critical calls I'm
# using here.
for req, parent in e.causes:
logger.critical(
"Could not find a version that satisfies " +
"the requirement " + str(req) +
("" if parent is None else " (from {})".format(parent.
name)))
raise DistributionNotFound(
"No matching distribution found for " +
", ".join([r.name for r, _ in e.causes]))
six.raise_from(error, e)
req_set = RequirementSet(check_supported_wheels=check_supported_wheels)
for candidate in self._result.mapping.values():
ireq = candidate.get_install_requirement()
if ireq is None:
continue
ireq.should_reinstall = self.factory.should_reinstall(candidate)
req_set.add_named_requirement(ireq)
return req_set
def get_installation_error(
self,
e: "ResolutionImpossible[Requirement, Candidate]",
constraints: Dict[str, Constraint],
) -> InstallationError:
assert e.causes, "Installation error reported with no cause"
# If one of the things we can't solve is "we need Python X.Y",
# that is what we report.
requires_python_causes = [
cause for cause in e.causes
if isinstance(cause.requirement, RequiresPythonRequirement)
and not cause.requirement.is_satisfied_by(self._python_candidate)
]
if requires_python_causes:
# The comprehension above makes sure all Requirement instances are
# RequiresPythonRequirement, so let's cast for convinience.
return self._report_requires_python_error(
cast("Sequence[ConflictCause]", requires_python_causes), )
# Otherwise, we have a set of causes which can't all be satisfied
# at once.
# The simplest case is when we have *one* cause that can't be
# satisfied. We just report that case.
if len(e.causes) == 1:
req, parent = e.causes[0]
if req.name not in constraints:
return self._report_single_requirement_conflict(req, parent)
# OK, we now have a list of requirements that can't all be
# satisfied at once.
# A couple of formatting helpers
def text_join(parts: List[str]) -> str:
if len(parts) == 1:
return parts[0]
return ", ".join(parts[:-1]) + " and " + parts[-1]
def describe_trigger(parent: Candidate) -> str:
ireq = parent.get_install_requirement()
if not ireq or not ireq.comes_from:
return f"{parent.name}=={parent.version}"
if isinstance(ireq.comes_from, InstallRequirement):
return str(ireq.comes_from.name)
return str(ireq.comes_from)
triggers = set()
for req, parent in e.causes:
if parent is None:
# This is a root requirement, so we can report it directly
trigger = req.format_for_error()
else:
trigger = describe_trigger(parent)
triggers.add(trigger)
if triggers:
info = text_join(sorted(triggers))
else:
info = "the requested packages"
msg = ("Cannot install {} because these package versions "
"have conflicting dependencies.".format(info))
logger.critical(msg)
msg = "\nThe conflict is caused by:"
relevant_constraints = set()
for req, parent in e.causes:
if req.name in constraints:
relevant_constraints.add(req.name)
msg = msg + "\n "
if parent:
msg = msg + f"{parent.name} {parent.version} depends on "
else:
msg = msg + "The user requested "
msg = msg + req.format_for_error()
for key in relevant_constraints:
spec = constraints[key].specifier
msg += f"\n The user requested (constraint) {key}{spec}"
msg = (msg + "\n\n" + "To fix this you could try to:\n" +
"1. loosen the range of package versions you've specified\n" +
"2. remove package versions to allow pip attempt to solve " +
"the dependency conflict\n")
logger.info(msg)
return DistributionNotFound("ResolutionImpossible: for help visit "
"https://pip.pypa.io/en/latest/user_guide/"
"#fixing-conflicting-dependencies")
def get_installation_error(self, e):
# type: (ResolutionImpossible) -> InstallationError
assert e.causes, "Installation error reported with no cause"
# If one of the things we can't solve is "we need Python X.Y",
# that is what we report.
for cause in e.causes:
if isinstance(cause.requirement, RequiresPythonRequirement):
return self._report_requires_python_error(
cause.requirement,
cause.parent,
)
# Otherwise, we have a set of causes which can't all be satisfied
# at once.
# The simplest case is when we have *one* cause that can't be
# satisfied. We just report that case.
if len(e.causes) == 1:
req, parent = e.causes[0]
if parent is None:
req_disp = str(req)
else:
req_disp = f'{req} (from {parent.name})'
logger.critical(
"Could not find a version that satisfies the requirement %s",
req_disp,
)
return DistributionNotFound(
f'No matching distribution found for {req}'
)
# OK, we now have a list of requirements that can't all be
# satisfied at once.
# A couple of formatting helpers
def text_join(parts):
# type: (List[str]) -> str
if len(parts) == 1:
return parts[0]
return ", ".join(parts[:-1]) + " and " + parts[-1]
def describe_trigger(parent):
# type: (Candidate) -> str
ireq = parent.get_install_requirement()
if not ireq or not ireq.comes_from:
return f"{parent.name}=={parent.version}"
if isinstance(ireq.comes_from, InstallRequirement):
return str(ireq.comes_from.name)
return str(ireq.comes_from)
triggers = set()
for req, parent in e.causes:
if parent is None:
# This is a root requirement, so we can report it directly
trigger = req.format_for_error()
else:
trigger = describe_trigger(parent)
triggers.add(trigger)
if triggers:
info = text_join(sorted(triggers))
else:
info = "the requested packages"
msg = "Cannot install {} because these package versions " \
"have conflicting dependencies.".format(info)
info = "the requested packages"
msg = "Cannot install {} because these package versions " \
"have conflicting dependencies.".format(info)
logger.critical(msg)
msg = "\nThe conflict is caused by:"
for req, parent in e.causes:
msg = msg + "\n "
if parent:
msg = msg + "{} {} depends on ".format(
parent.name,
parent.version
)
else:
msg = msg + "The user requested "
msg = msg + req.format_for_error()
msg = msg + "\n\n" + \
"To fix this you could try to:\n" + \
"1. loosen the range of package versions you've specified\n" + \
"2. remove package versions to allow pip attempt to solve " + \
"the dependency conflict\n"
logger.info(msg)
return DistributionNotFound(
"ResolutionImpossible: for help visit "
"https://pip.pypa.io/en/latest/user_guide/"
"#fixing-conflicting-dependencies"
)
def resolve(self, root_reqs, check_supported_wheels):
# type: (List[InstallRequirement], bool) -> RequirementSet
constraints = {} # type: Dict[str, SpecifierSet]
user_requested = set() # type: Set[str]
requirements = []
for req in root_reqs:
if req.constraint:
# Ensure we only accept valid constraints
reject_invalid_constraint_types(req)
name = canonicalize_name(req.name)
if name in constraints:
constraints[name] = constraints[name] & req.specifier
else:
constraints[name] = req.specifier
else:
if req.is_direct and req.name:
user_requested.add(canonicalize_name(req.name))
r = self.factory.make_requirement_from_install_req(
req,
requested_extras=(),
)
if r is not None:
requirements.append(r)
provider = PipProvider(
factory=self.factory,
constraints=constraints,
ignore_dependencies=self.ignore_dependencies,
upgrade_strategy=self.upgrade_strategy,
user_requested=user_requested,
)
reporter = BaseReporter()
resolver = RLResolver(provider, reporter)
try:
try_to_avoid_resolution_too_deep = 2000000
self._result = resolver.resolve(
requirements,
max_rounds=try_to_avoid_resolution_too_deep,
)
except ResolutionImpossible as e:
error = self.factory.get_installation_error(e)
if not error:
# TODO: This needs fixing, we need to look at the
# factory.get_installation_error infrastructure, as that
# doesn't really allow for the logger.critical calls I'm
# using here.
for req, parent in e.causes:
logger.critical(
"Could not find a version that satisfies " +
"the requirement " + str(req) +
("" if parent is None else " (from {})".format(parent.
name)))
raise DistributionNotFound(
"No matching distribution found for " +
", ".join([r.name for r, _ in e.causes]))
six.raise_from(error, e)
req_set = RequirementSet(check_supported_wheels=check_supported_wheels)
for candidate in self._result.mapping.values():
ireq = candidate.get_install_requirement()
if ireq is None:
continue
link = candidate.source_link
if link and link.is_yanked:
# The reason can contain non-ASCII characters, Unicode
# is required for Python 2.
msg = (
u'The candidate selected for download or install is a '
u'yanked version: {name!r} candidate (version {version} '
u'at {link})\nReason for being yanked: {reason}').format(
name=candidate.name,
version=candidate.version,
link=link,
reason=link.yanked_reason or u'<none given>',
)
logger.warning(msg)
ireq.should_reinstall = self.factory.should_reinstall(candidate)
req_set.add_named_requirement(ireq)
return req_set
