+# pinch: PIN CHannels - a replacement for `nix-channel --update`
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation, version 3.
+
+
import argparse
import configparser
import filecmp
import shutil
import subprocess
import sys
+import tarfile
import tempfile
import types
import urllib.parse
import xml.dom.minidom
from typing import (
+ Callable,
Dict,
Iterable,
List,
Union,
)
+import git_cache
+
# Use xdg module when it's less painful to have as a dependency
@staticmethod
def _color(s: str, c: int) -> str:
- return '\033[%2dm%s\033[00m' % (c, s)
+ return f'\033[{c:2d}m{s}\033[00m'
def result(self, r: bool) -> None:
message, color = {True: ('OK ', 92), False: ('FAIL', 91)}[r]
pass
+class SymlinkPin(NamedTuple):
+ @property
+ def release_name(self) -> str:
+ return 'link'
+
+
class GitPin(NamedTuple):
git_revision: str
release_name: str
tarball_sha256: str
-Pin = Union[AliasPin, GitPin, ChannelPin]
+Pin = Union[AliasPin, SymlinkPin, GitPin, ChannelPin]
+
+
+def copy_to_nix_store(v: Verification, filename: str) -> str:
+ v.status('Putting tarball in Nix store')
+ process = subprocess.run(
+ ['nix-store', '--add', filename], stdout=subprocess.PIPE)
+ v.result(process.returncode == 0)
+ return process.stdout.decode().strip() # type: ignore # (for old mypy)
+
+
+def symlink_archive(v: Verification, path: str) -> str:
+ with tempfile.TemporaryDirectory() as td:
+ archive_filename = os.path.join(td, 'link.tar.gz')
+ os.symlink(path, os.path.join(td, 'link'))
+ with tarfile.open(archive_filename, mode='x:gz') as t:
+ t.add(os.path.join(td, 'link'), arcname='link')
+ return copy_to_nix_store(v, archive_filename)
class AliasSearchPath(NamedTuple):
alias_of: str
- # pylint: disable=no-self-use
def pin(self, _: Verification, __: Optional[Pin]) -> AliasPin:
return AliasPin()
+class SymlinkSearchPath(NamedTuple):
+ path: str
+
+ def pin(self, _: Verification, __: Optional[Pin]) -> SymlinkPin:
+ return SymlinkPin()
+
+ def fetch(self, v: Verification, _: Pin) -> str:
+ return symlink_archive(v, self.path)
+
+
class GitSearchPath(NamedTuple):
git_ref: str
git_repo: str
def pin(self, v: Verification, old_pin: Optional[Pin]) -> GitPin:
+ _, new_revision = git_cache.fetch(self.git_repo, self.git_ref)
if old_pin is not None:
assert isinstance(old_pin, GitPin)
- old_revision = old_pin.git_revision if old_pin is not None else None
-
- new_revision = git_fetch(v, self, None, old_revision)
+ verify_git_ancestry(v, self, old_pin.git_revision, new_revision)
return GitPin(release_name=git_revision_name(v, self, new_revision),
git_revision=new_revision)
def fetch(self, v: Verification, pin: Pin) -> str:
assert isinstance(pin, GitPin)
- ensure_git_rev_available(v, self, pin, None)
+ git_cache.ensure_rev_available(
+ self.git_repo, self.git_ref, pin.git_revision)
return git_get_tarball(v, self, pin)
def pin(self, v: Verification, old_pin: Optional[Pin]) -> ChannelPin:
if old_pin is not None:
assert isinstance(old_pin, ChannelPin)
- old_revision = old_pin.git_revision if old_pin is not None else None
channel_html, forwarded_url = fetch_channel(v, self)
table, new_gitpin = parse_channel(v, channel_html)
+ if old_pin is not None and old_pin.git_revision == new_gitpin.git_revision:
+ return old_pin
fetch_resources(v, new_gitpin, forwarded_url, table)
- ensure_git_rev_available(v, self, new_gitpin, old_revision)
+ git_cache.ensure_rev_available(
+ self.git_repo, self.git_ref, new_gitpin.git_revision)
+ if old_pin is not None:
+ verify_git_ancestry(
+ v, self, old_pin.git_revision, new_gitpin.git_revision)
check_channel_contents(v, self, table, new_gitpin)
return ChannelPin(
release_name=new_gitpin.release_name,
tarball_sha256=table['nixexprs.tar.xz'].digest,
git_revision=new_gitpin.git_revision)
- # pylint: disable=no-self-use
def fetch(self, v: Verification, pin: Pin) -> str:
assert isinstance(pin, ChannelPin)
v, pin.tarball_url, Digest16(pin.tarball_sha256))
-SearchPath = Union[AliasSearchPath, GitSearchPath, ChannelSearchPath]
+SearchPath = Union[AliasSearchPath,
+ SymlinkSearchPath,
+ GitSearchPath,
+ ChannelSearchPath]
TarrableSearchPath = Union[GitSearchPath, ChannelSearchPath]
def fetch_channel(
v: Verification, channel: ChannelSearchPath) -> Tuple[str, str]:
- v.status('Fetching channel')
- request = urllib.request.urlopen(channel.channel_url, timeout=10)
- channel_html = request.read()
- forwarded_url = request.geturl()
- v.result(request.status == 200) # type: ignore # (for old mypy)
+ v.status(f'Fetching channel from {channel.channel_url}')
+ with urllib.request.urlopen(channel.channel_url, timeout=10) as request:
+ channel_html = request.read().decode()
+ forwarded_url = request.geturl()
+ v.result(request.status == 200)
v.check('Got forwarded', channel.channel_url != forwarded_url)
return channel_html, forwarded_url
return Digest16(hasher.hexdigest())
+@functools.lru_cache
+def _experimental_flag_needed(v: Verification) -> bool:
+ v.status('Checking Nix version')
+ process = subprocess.run(['nix', '--help'], stdout=subprocess.PIPE)
+ v.result(process.returncode == 0)
+ return b'--experimental-features' in process.stdout
+
+
+def _nix_command(v: Verification) -> List[str]:
+ return ['nix', '--experimental-features',
+ 'nix-command'] if _experimental_flag_needed(v) else ['nix']
+
+
def to_Digest16(v: Verification, digest32: Digest32) -> Digest16:
v.status('Converting digest to base16')
- process = subprocess.run(
- ['nix', 'to-base16', '--type', 'sha256', digest32], stdout=subprocess.PIPE)
+ process = subprocess.run(_nix_command(v) + [
+ 'to-base16',
+ '--type',
+ 'sha256',
+ digest32],
+ stdout=subprocess.PIPE)
v.result(process.returncode == 0)
return Digest16(process.stdout.decode().strip())
def to_Digest32(v: Verification, digest16: Digest16) -> Digest32:
v.status('Converting digest to base32')
- process = subprocess.run(
- ['nix', 'to-base32', '--type', 'sha256', digest16], stdout=subprocess.PIPE)
+ process = subprocess.run(_nix_command(v) + [
+ 'to-base32',
+ '--type',
+ 'sha256',
+ digest16],
+ stdout=subprocess.PIPE)
v.result(process.returncode == 0)
return Digest32(process.stdout.decode().strip())
v: Verification,
url: str,
digest: Digest16) -> str:
- v.status('Fetching %s' % url)
+ v.status(f'Fetching {url}')
process = subprocess.run(
['nix-prefetch-url', '--print-path', url, digest], stdout=subprocess.PIPE)
v.result(process.returncode == 0)
assert empty == ''
v.check("Verifying nix-prefetch-url's digest",
to_Digest16(v, Digest32(prefetch_digest)) == digest)
- v.status("Verifying file digest")
+ v.status(f"Verifying digest of {path}")
file_digest = digest_file(path)
v.result(file_digest == digest)
return path # type: ignore # (for old mypy)
fields.file = fetch_with_nix_prefetch_url(
v, fields.absolute_url, fields.digest)
v.status('Verifying git commit on main page matches git commit in table')
- v.result(open(table['git-revision'].file).read(999) == pin.git_revision)
-
-
-def git_cachedir(git_repo: str) -> str:
- return os.path.join(
- xdg.XDG_CACHE_HOME,
- 'pinch/git',
- digest_string(git_repo.encode()))
+ with open(table['git-revision'].file, encoding='utf-8') as rev_file:
+ v.result(rev_file.read(999) == pin.git_revision)
def tarball_cache_file(channel: TarrableSearchPath, pin: GitPin) -> str:
return os.path.join(
xdg.XDG_CACHE_HOME,
'pinch/git-tarball',
- '%s-%s-%s' %
- (digest_string(channel.git_repo.encode()),
- pin.git_revision,
- pin.release_name))
+ f'{digest_string(channel.git_repo.encode())}-{pin.git_revision}-{pin.release_name}')
def verify_git_ancestry(
v: Verification,
channel: TarrableSearchPath,
- new_revision: str,
- old_revision: Optional[str]) -> None:
- cachedir = git_cachedir(channel.git_repo)
- v.status('Verifying rev is an ancestor of ref')
+ old_revision: str,
+ new_revision: str) -> None:
+ cachedir = git_cache.git_cachedir(channel.git_repo)
+ v.status(f'Verifying rev is an ancestor of previous rev {old_revision}')
process = subprocess.run(['git',
'-C',
cachedir,
'merge-base',
'--is-ancestor',
- new_revision,
- channel.git_ref])
+ old_revision,
+ new_revision])
v.result(process.returncode == 0)
- if old_revision is not None:
- v.status(
- 'Verifying rev is an ancestor of previous rev %s' %
- old_revision)
- process = subprocess.run(['git',
- '-C',
- cachedir,
- 'merge-base',
- '--is-ancestor',
- old_revision,
- new_revision])
- v.result(process.returncode == 0)
-
-
-def git_fetch(
- v: Verification,
- channel: TarrableSearchPath,
- desired_revision: Optional[str],
- old_revision: Optional[str]) -> str:
- # It would be nice if we could share the nix git cache, but as of the time
- # of writing it is transitioning from gitv2 (deprecated) to gitv3 (not ready
- # yet), and trying to straddle them both is too far into nix implementation
- # details for my comfort. So we re-implement here half of nix.fetchGit.
- # :(
-
- cachedir = git_cachedir(channel.git_repo)
- if not os.path.exists(cachedir):
- v.status("Initializing git repo")
- process = subprocess.run(
- ['git', 'init', '--bare', cachedir])
- v.result(process.returncode == 0)
-
- v.status('Fetching ref "%s" from %s' % (channel.git_ref, channel.git_repo))
- # We don't use --force here because we want to abort and freak out if forced
- # updates are happening.
- process = subprocess.run(['git',
- '-C',
- cachedir,
- 'fetch',
- channel.git_repo,
- '%s:%s' % (channel.git_ref,
- channel.git_ref)])
- v.result(process.returncode == 0)
-
- if desired_revision is not None:
- v.status('Verifying that fetch retrieved this rev')
- process = subprocess.run(
- ['git', '-C', cachedir, 'cat-file', '-e', desired_revision])
- v.result(process.returncode == 0)
-
- new_revision = open(
- os.path.join(
- cachedir,
- 'refs',
- 'heads',
- channel.git_ref)).read(999).strip()
-
- verify_git_ancestry(v, channel, new_revision, old_revision)
-
- return new_revision
-
-
-def ensure_git_rev_available(
- v: Verification,
- channel: TarrableSearchPath,
- pin: GitPin,
- old_revision: Optional[str]) -> None:
- cachedir = git_cachedir(channel.git_repo)
- if os.path.exists(cachedir):
- v.status('Checking if we already have this rev:')
- process = subprocess.run(
- ['git', '-C', cachedir, 'cat-file', '-e', pin.git_revision])
- if process.returncode == 0:
- v.status('yes')
- if process.returncode == 1:
- v.status('no')
- v.result(process.returncode == 0 or process.returncode == 1)
- if process.returncode == 0:
- verify_git_ancestry(v, channel, pin.git_revision, old_revision)
- return
- git_fetch(v, channel, pin.git_revision, old_revision)
-
def compare_tarball_and_git(
v: Verification,
match, mismatch, errors = compare(os.path.join(
channel_contents, pin.release_name), git_contents)
v.ok()
- v.check('%d files match' % len(match), len(match) > 0)
- v.check('%d files differ' % len(mismatch), len(mismatch) == 0)
+ v.check(f'{len(match)} files match', len(match) > 0)
+ v.check(f'{len(mismatch)} files differ', len(mismatch) == 0)
expected_errors = [
'.git-revision',
'.version-suffix',
errors.remove(ee)
benign_errors.append(ee)
v.check(
- '%d unexpected incomparable files' %
- len(errors),
+ f'{len(errors)} unexpected incomparable files: {errors}',
len(errors) == 0)
v.check(
- '(%d of %d expected incomparable files)' %
- (len(benign_errors),
- len(expected_errors)),
+ f'({len(benign_errors)} of {len(expected_errors)} expected incomparable files)',
len(benign_errors) == len(expected_errors))
v: Verification,
table: Dict[str, ChannelTableEntry],
dest: str) -> None:
- v.status('Extracting tarball %s' % table['nixexprs.tar.xz'].file)
+ v.status(f"Extracting tarball {table['nixexprs.tar.xz'].file}")
shutil.unpack_archive(table['nixexprs.tar.xz'].file, dest)
v.ok()
pin: GitPin,
dest: str) -> None:
v.status('Checking out corresponding git revision')
- git = subprocess.Popen(['git',
- '-C',
- git_cachedir(channel.git_repo),
- 'archive',
- pin.git_revision],
- stdout=subprocess.PIPE)
- tar = subprocess.Popen(
- ['tar', 'x', '-C', dest, '-f', '-'], stdin=git.stdout)
- if git.stdout:
- git.stdout.close()
- tar.wait()
- git.wait()
- v.result(git.returncode == 0 and tar.returncode == 0)
+ with subprocess.Popen(
+ ['git', '-C', git_cache.git_cachedir(channel.git_repo), 'archive', pin.git_revision],
+ stdout=subprocess.PIPE) as git:
+ with subprocess.Popen(['tar', 'x', '-C', dest, '-f', '-'], stdin=git.stdout) as tar:
+ if git.stdout:
+ git.stdout.close()
+ tar.wait()
+ git.wait()
+ v.result(git.returncode == 0 and tar.returncode == 0)
def git_get_tarball(
pin: GitPin) -> str:
cache_file = tarball_cache_file(channel, pin)
if os.path.exists(cache_file):
- cached_tarball = open(cache_file).read(9999)
- if os.path.exists(cached_tarball):
- return cached_tarball
+ with open(cache_file, encoding='utf-8') as f:
+ cached_tarball = f.read(9999)
+ if os.path.exists(cached_tarball):
+ return cached_tarball
with tempfile.TemporaryDirectory() as output_dir:
output_filename = os.path.join(
output_dir, pin.release_name + '.tar.xz')
- with open(output_filename, 'w') as output_file:
- v.status(
- 'Generating tarball for git revision %s' %
- pin.git_revision)
- git = subprocess.Popen(['git',
- '-C',
- git_cachedir(channel.git_repo),
- 'archive',
- '--prefix=%s/' % pin.release_name,
- pin.git_revision],
- stdout=subprocess.PIPE)
- xz = subprocess.Popen(['xz'], stdin=git.stdout, stdout=output_file)
- xz.wait()
- git.wait()
- v.result(git.returncode == 0 and xz.returncode == 0)
-
- v.status('Putting tarball in Nix store')
- process = subprocess.run(
- ['nix-store', '--add', output_filename], stdout=subprocess.PIPE)
- v.result(process.returncode == 0)
- store_tarball = process.stdout.decode().strip()
+ with open(output_filename, 'w', encoding='utf-8') as output_file:
+ v.status(f'Generating tarball for git revision {pin.git_revision}')
+ with subprocess.Popen(
+ ['git', '-C', git_cache.git_cachedir(channel.git_repo),
+ 'archive', f'--prefix={pin.release_name}/', pin.git_revision],
+ stdout=subprocess.PIPE) as git:
+ with subprocess.Popen(['xz'], stdin=git.stdout, stdout=output_file) as xz:
+ xz.wait()
+ git.wait()
+ v.result(git.returncode == 0 and xz.returncode == 0)
+
+ store_tarball = copy_to_nix_store(v, output_filename)
os.makedirs(os.path.dirname(cache_file), exist_ok=True)
- open(cache_file, 'w').write(store_tarball)
+ with open(cache_file, 'w', encoding='utf-8') as f:
+ f.write(store_tarball)
return store_tarball # type: ignore # (for old mypy)
pin: GitPin,
channel_contents: str) -> None:
v.status('Verifying git commit in channel tarball')
- v.result(
- open(
- os.path.join(
- channel_contents,
- pin.release_name,
- '.git-revision')).read(999) == pin.git_revision)
+ with open(os.path.join(channel_contents, pin.release_name, '.git-revision'),
+ encoding='utf-8') as f:
+ v.result(f.read(999) == pin.git_revision)
v.status(
- 'Verifying version-suffix is a suffix of release name %s:' %
- pin.release_name)
- version_suffix = open(
- os.path.join(
- channel_contents,
- pin.release_name,
- '.version-suffix')).read(999)
+ f'Verifying version-suffix is a suffix of release name {pin.release_name}:')
+ with open(os.path.join(channel_contents, pin.release_name, '.version-suffix'),
+ encoding='utf-8') as f:
+ version_suffix = f.read(999)
v.status(version_suffix)
v.result(pin.release_name.endswith(version_suffix))
v.status('Getting commit date')
process = subprocess.run(['git',
'-C',
- git_cachedir(channel.git_repo),
+ git_cache.git_cachedir(channel.git_repo),
'log',
'-n1',
'--format=%ct-%h',
git_revision],
stdout=subprocess.PIPE)
v.result(process.returncode == 0 and process.stdout != b'')
- return '%s-%s' % (os.path.basename(channel.git_repo),
- process.stdout.decode().strip())
+ return f'{os.path.basename(channel.git_repo)}-{process.stdout.decode().strip()}'
K = TypeVar('K')
V = TypeVar('V')
-def filter_dict(d: Dict[K, V], fields: Set[K]
- ) -> Tuple[Dict[K, V], Dict[K, V]]:
+def partition_dict(pred: Callable[[K, V], bool],
+ d: Dict[K, V]) -> Tuple[Dict[K, V], Dict[K, V]]:
selected: Dict[K, V] = {}
remaining: Dict[K, V] = {}
for k, v in d.items():
- if k in fields:
+ if pred(k, v):
selected[k] = v
else:
remaining[k] = v
return selected, remaining
-def read_search_path(
+def filter_dict(d: Dict[K, V], fields: Set[K]
+ ) -> Tuple[Dict[K, V], Dict[K, V]]:
+ return partition_dict(lambda k, v: k in fields, d)
+
+
+def read_config_section(
conf: configparser.SectionProxy) -> Tuple[SearchPath, Optional[Pin]]:
mapping: Mapping[str, Tuple[Type[SearchPath], Type[Pin]]] = {
'alias': (AliasSearchPath, AliasPin),
'channel': (ChannelSearchPath, ChannelPin),
'git': (GitSearchPath, GitPin),
+ 'symlink': (SymlinkSearchPath, SymlinkPin),
}
SP, P = mapping[conf['type']]
_, all_fields = filter_dict(dict(conf.items()), set(['type']))
pin_fields, remaining_fields = filter_dict(all_fields, set(P._fields))
# Error suppression works around https://github.com/python/mypy/issues/9007
- pin_present = pin_fields != {} or P._fields == ()
- pin = P(**pin_fields) if pin_present else None # type:ignore[call-arg]
+ pin_present = pin_fields or P._fields == ()
+ pin = P(**pin_fields) if pin_present else None # type: ignore
return SP(**remaining_fields), pin
+def read_pinned_config_section(
+ section: str, conf: configparser.SectionProxy) -> Tuple[SearchPath, Pin]:
+ sp, pin = read_config_section(conf)
+ if pin is None:
+ raise RuntimeError(
+ f'Cannot update unpinned channel "{section}" (Run "pin" before "update")')
+ return sp, pin
+
+
def read_config(filename: str) -> configparser.ConfigParser:
config = configparser.ConfigParser()
- config.read_file(open(filename), filename)
+ with open(filename, encoding='utf-8') as f:
+ config.read_file(f, filename)
return config
config = read_config(file)
for section in config.sections():
if section in merged_config:
- raise Exception('Duplicate channel "%s"' % section)
+ raise RuntimeError('Duplicate channel "{section}"')
merged_config[section] = config[section]
return merged_config
if args.channels and section not in args.channels:
continue
- sp, old_pin = read_search_path(config[section])
+ sp, old_pin = read_config_section(config[section])
config[section].update(sp.pin(v, old_pin)._asdict())
- with open(args.channels_file, 'w') as configfile:
+ with open(args.channels_file, 'w', encoding='utf-8') as configfile:
config.write(configfile)
def updateCommand(args: argparse.Namespace) -> None:
v = Verification()
exprs: Dict[str, str] = {}
- config = read_config_files(args.channels_file)
- for section in config:
- sp, pin = read_search_path(config[section])
- if pin is None:
- raise Exception(
- 'Cannot update unpinned channel "%s" (Run "pin" before "update")' %
- section)
- if isinstance(sp, AliasSearchPath):
- assert 'git_repo' not in config[section]
- continue
+ profile_manifest = os.path.join(args.profile, "manifest.nix")
+ search_paths: List[str] = [
+ "-I", "pinch_profile=" + args.profile,
+ "-I", "pinch_profile_manifest=" + os.readlink(profile_manifest)
+ ] if os.path.exists(profile_manifest) else []
+ config = {
+ section: read_pinned_config_section(section, conf) for section,
+ conf in read_config_files(
+ args.channels_file).items()}
+ alias, nonalias = partition_dict(
+ lambda k, v: isinstance(v[0], AliasSearchPath), config)
+
+ for section, (sp, pin) in sorted(nonalias.items()):
+ assert not isinstance(sp, AliasSearchPath) # mypy can't see through
+ assert not isinstance(pin, AliasPin) # partition_dict()
tarball = sp.fetch(v, pin)
+ search_paths.extend(
+ ["-I", f"pinch_tarball_for_{pin.release_name}={tarball}"])
exprs[section] = (
- 'f: f { name = "%s"; channelName = "%%s"; src = builtins.storePath "%s"; }' %
- (config[section]['release_name'], tarball))
+ f'f: f {{ name = "{pin.release_name}"; channelName = "%s"; '
+ f'src = builtins.storePath "{tarball}"; }}')
- for section in config:
- if 'alias_of' in config[section]:
- exprs[section] = exprs[str(config[section]['alias_of'])]
+ for section, (sp, pin) in alias.items():
+ assert isinstance(sp, AliasSearchPath) # For mypy
+ exprs[section] = exprs[sp.alias_of]
command = [
'nix-env',
'--profile',
- '/nix/var/nix/profiles/per-user/%s/channels' %
- getpass.getuser(),
+ args.profile,
'--show-trace',
'--file',
'<nix/unpack-channel.nix>',
'--install',
- '--from-expression'] + [exprs[name] % name for name in sorted(exprs.keys())]
+ '--remove-all',
+ ] + search_paths + ['--from-expression'] + [
+ exprs[name] % name for name in sorted(exprs.keys())]
if args.dry_run:
print(' '.join(map(shlex.quote, command)))
else:
parser_pin.set_defaults(func=pinCommand)
parser_update = subparsers.add_parser('update')
parser_update.add_argument('--dry-run', action='store_true')
+ parser_update.add_argument('--profile', default=(
+ f'/nix/var/nix/profiles/per-user/{getpass.getuser()}/channels'))
parser_update.add_argument('channels_file', type=str, nargs='+')
parser_update.set_defaults(func=updateCommand)
args = parser.parse_args()