+from abc import ABC, abstractmethod
+import argparse
+import configparser
import filecmp
import functools
+import getpass
import hashlib
import operator
import os
import os.path
+import shlex
import shutil
+import subprocess
+import sys
import tempfile
+import types
import urllib.parse
import urllib.request
import xml.dom.minidom
from typing import (
- Any,
Dict,
Iterable,
List,
- Sequence,
+ NamedTuple,
+ NewType,
Tuple,
+ Union,
)
+# Use xdg module when it's less painful to have as a dependency
+
+
+class XDG(types.SimpleNamespace):
+ XDG_CACHE_HOME: str
+
+
+xdg = XDG(
+ XDG_CACHE_HOME=os.getenv(
+ 'XDG_CACHE_HOME',
+ os.path.expanduser('~/.cache')))
+
class VerificationError(Exception):
pass
self.line_length = 0
def status(self, s: str) -> None:
- print(s, end=' ', flush=True)
+ print(s, end=' ', file=sys.stderr, flush=True)
self.line_length += 1 + len(s) # Unicode??
@staticmethod
def result(self, r: bool) -> None:
message, color = {True: ('OK ', 92), False: ('FAIL', 91)}[r]
length = len(message)
- cols = shutil.get_terminal_size().columns
+ cols = shutil.get_terminal_size().columns or 80
pad = (cols - (self.line_length + length)) % cols
- print(' ' * pad + self._color(message, color))
+ print(' ' * pad + self._color(message, color), file=sys.stderr)
self.line_length = 0
if not r:
raise VerificationError()
self.result(True)
-def compare(a: str,
- b: str) -> Tuple[Sequence[str],
- Sequence[str],
- Sequence[str]]:
+Digest16 = NewType('Digest16', str)
+Digest32 = NewType('Digest32', str)
+
+
+class ChannelTableEntry(types.SimpleNamespace):
+ absolute_url: str
+ digest: Digest16
+ file: str
+ size: int
+ url: str
+
+
+class AliasPin(NamedTuple):
+ pass
+
+
+class GitPin(NamedTuple):
+ git_revision: str
+ release_name: str
+
+
+class ChannelPin(NamedTuple):
+ git_revision: str
+ release_name: str
+ tarball_url: str
+ tarball_sha256: str
+
+
+Pin = Union[AliasPin, GitPin, ChannelPin]
+
+
+class SearchPath(types.SimpleNamespace, ABC):
+
+ @abstractmethod
+ def pin(self, v: Verification) -> Pin:
+ pass
+
+
+class AliasSearchPath(SearchPath):
+ alias_of: str
+
+ def pin(self, v: Verification) -> AliasPin:
+ assert not hasattr(self, 'git_repo')
+ return AliasPin()
+
+
+# (This lint-disable is for pylint bug https://github.com/PyCQA/pylint/issues/179
+# which is fixed in pylint 2.5.)
+class TarrableSearchPath(SearchPath, ABC): # pylint: disable=abstract-method
+ channel_html: bytes
+ channel_url: str
+ forwarded_url: str
+ git_ref: str
+ git_repo: str
+ old_git_revision: str
+ table: Dict[str, ChannelTableEntry]
+
+
+class GitSearchPath(TarrableSearchPath):
+ def pin(self, v: Verification) -> GitPin:
+ if hasattr(self, 'git_revision'):
+ self.old_git_revision = self.git_revision
+ del self.git_revision
+
+ git_fetch(v, self)
+ return GitPin(release_name=git_revision_name(v, self),
+ git_revision=self.git_revision)
+
+ def fetch(self, v: Verification, section: str,
+ conf: configparser.SectionProxy) -> str:
+ if 'git_repo' not in conf or 'release_name' not in conf:
+ raise Exception(
+ 'Cannot update unpinned channel "%s" (Run "pin" before "update")' %
+ section)
+
+ ensure_git_rev_available(v, self)
+ return git_get_tarball(v, self)
+
+
+class ChannelSearchPath(TarrableSearchPath):
+ def pin(self, v: Verification) -> ChannelPin:
+ if hasattr(self, 'git_revision'):
+ self.old_git_revision = self.git_revision
+ del self.git_revision
+
+ pin_channel(v, self)
+ return ChannelPin(
+ release_name=self.release_name,
+ tarball_url=self.table['nixexprs.tar.xz'].absolute_url,
+ tarball_sha256=self.table['nixexprs.tar.xz'].digest,
+ git_revision=self.git_revision)
+
+ # Lint TODO: Put tarball_url and tarball_sha256 in ChannelSearchPath
+ # pylint: disable=no-self-use
+ def fetch(self, v: Verification, section: str,
+ conf: configparser.SectionProxy) -> str:
+ if 'git_repo' not in conf or 'release_name' not in conf:
+ raise Exception(
+ 'Cannot update unpinned channel "%s" (Run "pin" before "update")' %
+ section)
+
+ return fetch_with_nix_prefetch_url(
+ v, conf['tarball_url'], Digest16(
+ conf['tarball_sha256']))
+
+
+def compare(a: str, b: str) -> Tuple[List[str], List[str], List[str]]:
def throw(error: OSError) -> None:
raise error
return filecmp.cmpfiles(a, b, files, shallow=False)
-def fetch(v: Verification, channel_url: str) -> Dict[str, Any]:
- info: Dict[str, Any] = {'url': channel_url}
+def fetch(v: Verification, channel: TarrableSearchPath) -> None:
v.status('Fetching channel')
- request = urllib.request.urlopen(
- 'https://channels.nixos.org/nixos-20.03', timeout=10)
- info['channel_html'] = request.read()
- info['forwarded_url'] = request.geturl()
- v.result(request.status == 200)
- v.check('Got forwarded', info['url'] != info['forwarded_url'])
- return info
+ request = urllib.request.urlopen(channel.channel_url, timeout=10)
+ channel.channel_html = request.read()
+ channel.forwarded_url = request.geturl()
+ v.result(request.status == 200) # type: ignore # (for old mypy)
+ v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
-def parse(v: Verification, info: Dict[str, Any]) -> None:
+def parse_channel(v: Verification, channel: TarrableSearchPath) -> None:
v.status('Parsing channel description as XML')
- d = xml.dom.minidom.parseString(info['channel_html'])
+ d = xml.dom.minidom.parseString(channel.channel_html)
v.ok()
- v.status('Extracting git commit')
+ v.status('Extracting release name:')
+ title_name = d.getElementsByTagName(
+ 'title')[0].firstChild.nodeValue.split()[2]
+ h1_name = d.getElementsByTagName('h1')[0].firstChild.nodeValue.split()[2]
+ v.status(title_name)
+ v.result(title_name == h1_name)
+ channel.release_name = title_name
+
+ v.status('Extracting git commit:')
git_commit_node = d.getElementsByTagName('tt')[0]
- info['git_commit'] = git_commit_node.firstChild.nodeValue
+ channel.git_revision = git_commit_node.firstChild.nodeValue
+ v.status(channel.git_revision)
v.ok()
v.status('Verifying git commit label')
v.result(git_commit_node.previousSibling.nodeValue == 'Git commit ')
v.status('Parsing table')
- info['table'] = {}
+ channel.table = {}
for row in d.getElementsByTagName('tr')[1:]:
name = row.childNodes[0].firstChild.firstChild.nodeValue
url = row.childNodes[0].firstChild.getAttribute('href')
size = int(row.childNodes[1].firstChild.nodeValue)
- digest = row.childNodes[2].firstChild.firstChild.nodeValue
- info['table'][name] = {'url': url, 'digest': digest, 'size': size}
+ digest = Digest16(row.childNodes[2].firstChild.firstChild.nodeValue)
+ channel.table[name] = ChannelTableEntry(
+ url=url, digest=digest, size=size)
v.ok()
-def fetch_resources(v: Verification, info: Dict[str, Any]) -> None:
+def digest_string(s: bytes) -> Digest16:
+ return Digest16(hashlib.sha256(s).hexdigest())
+
+
+def digest_file(filename: str) -> Digest16:
+ hasher = hashlib.sha256()
+ with open(filename, 'rb') as f:
+ # pylint: disable=cell-var-from-loop
+ for block in iter(lambda: f.read(4096), b''):
+ hasher.update(block)
+ return Digest16(hasher.hexdigest())
+
+
+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)
+ 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)
+ v.result(process.returncode == 0)
+ return Digest32(process.stdout.decode().strip())
+
+def fetch_with_nix_prefetch_url(
+ v: Verification,
+ url: str,
+ digest: Digest16) -> str:
+ v.status('Fetching %s' % url)
+ process = subprocess.run(
+ ['nix-prefetch-url', '--print-path', url, digest], stdout=subprocess.PIPE)
+ v.result(process.returncode == 0)
+ prefetch_digest, path, empty = process.stdout.decode().split('\n')
+ assert empty == ''
+ v.check("Verifying nix-prefetch-url's digest",
+ to_Digest16(v, Digest32(prefetch_digest)) == digest)
+ v.status("Verifying file digest")
+ file_digest = digest_file(path)
+ v.result(file_digest == digest)
+ return path # type: ignore # (for old mypy)
+
+
+def fetch_resources(v: Verification, channel: TarrableSearchPath) -> None:
for resource in ['git-revision', 'nixexprs.tar.xz']:
- fields = info['table'][resource]
- v.status('Fetching resource "%s"' % resource)
- url = urllib.parse.urljoin(info['forwarded_url'], fields['url'])
- request = urllib.request.urlopen(url, timeout=10)
- if fields['size'] < 4096:
- fields['content'] = request.read()
- else:
- with tempfile.NamedTemporaryFile(suffix='.nixexprs.tar.xz', delete=False) as tmp_file:
- shutil.copyfileobj(request, tmp_file)
- fields['file'] = tmp_file.name
- v.result(request.status == 200)
- v.status('Verifying digest for "%s"' % resource)
- if fields['size'] < 4096:
- actual_hash = hashlib.sha256(fields['content']).hexdigest()
- else:
- hasher = hashlib.sha256()
- with open(fields['file'], 'rb') as f:
- # pylint: disable=cell-var-from-loop
- for block in iter(lambda: f.read(4096), b''):
- hasher.update(block)
- actual_hash = hasher.hexdigest()
- v.result(actual_hash == fields['digest'])
- v.check('Verifying git commit on main page matches git commit in table',
- info['table']['git-revision']['content'].decode() == info['git_commit'])
-
-
-def extract_channel(v: Verification, info: Dict[str, Any]) -> None:
- with tempfile.TemporaryDirectory() as d:
- v.status('Extracting nixexprs.tar.xz')
- shutil.unpack_archive(info['table']['nixexprs.tar.xz']['file'], d)
- v.ok()
- v.status('Removing temporary directory')
+ fields = channel.table[resource]
+ fields.absolute_url = urllib.parse.urljoin(
+ channel.forwarded_url, fields.url)
+ 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(
+ channel.table['git-revision'].file).read(999) == channel.git_revision)
+
+
+def git_cachedir(git_repo: str) -> str:
+ return os.path.join(
+ xdg.XDG_CACHE_HOME,
+ 'pinch/git',
+ digest_string(git_repo.encode()))
+
+
+def tarball_cache_file(channel: TarrableSearchPath) -> str:
+ return os.path.join(
+ xdg.XDG_CACHE_HOME,
+ 'pinch/git-tarball',
+ '%s-%s-%s' %
+ (digest_string(channel.git_repo.encode()),
+ channel.git_revision,
+ channel.release_name))
+
+
+def verify_git_ancestry(v: Verification, channel: TarrableSearchPath) -> None:
+ cachedir = git_cachedir(channel.git_repo)
+ v.status('Verifying rev is an ancestor of ref')
+ process = subprocess.run(['git',
+ '-C',
+ cachedir,
+ 'merge-base',
+ '--is-ancestor',
+ channel.git_revision,
+ channel.git_ref])
+ v.result(process.returncode == 0)
+
+ if hasattr(channel, 'old_git_revision'):
+ v.status(
+ 'Verifying rev is an ancestor of previous rev %s' %
+ channel.old_git_revision)
+ process = subprocess.run(['git',
+ '-C',
+ cachedir,
+ 'merge-base',
+ '--is-ancestor',
+ channel.old_git_revision,
+ channel.git_revision])
+ v.result(process.returncode == 0)
+
+
+def git_fetch(v: Verification, channel: TarrableSearchPath) -> None:
+ # 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 hasattr(channel, 'git_revision'):
+ v.status('Verifying that fetch retrieved this rev')
+ process = subprocess.run(
+ ['git', '-C', cachedir, 'cat-file', '-e', channel.git_revision])
+ v.result(process.returncode == 0)
+ else:
+ channel.git_revision = open(
+ os.path.join(
+ cachedir,
+ 'refs',
+ 'heads',
+ channel.git_ref)).read(999).strip()
+
+ verify_git_ancestry(v, channel)
+
+
+def ensure_git_rev_available(
+ v: Verification,
+ channel: TarrableSearchPath) -> 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', channel.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)
+ return
+ git_fetch(v, channel)
+
+
+def compare_tarball_and_git(
+ v: Verification,
+ channel: TarrableSearchPath,
+ channel_contents: str,
+ git_contents: str) -> None:
+ v.status('Comparing channel tarball with git checkout')
+ match, mismatch, errors = compare(os.path.join(
+ channel_contents, channel.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)
+ expected_errors = [
+ '.git-revision',
+ '.version-suffix',
+ 'nixpkgs',
+ 'programs.sqlite',
+ 'svn-revision']
+ benign_errors = []
+ for ee in expected_errors:
+ if ee in errors:
+ errors.remove(ee)
+ benign_errors.append(ee)
+ v.check(
+ '%d unexpected incomparable files' %
+ len(errors),
+ len(errors) == 0)
+ v.check(
+ '(%d of %d expected incomparable files)' %
+ (len(benign_errors),
+ len(expected_errors)),
+ len(benign_errors) == len(expected_errors))
+
+
+def extract_tarball(
+ v: Verification,
+ channel: TarrableSearchPath,
+ dest: str) -> None:
+ v.status('Extracting tarball %s' %
+ channel.table['nixexprs.tar.xz'].file)
+ shutil.unpack_archive(
+ channel.table['nixexprs.tar.xz'].file,
+ dest)
v.ok()
-def main() -> None:
+def git_checkout(
+ v: Verification,
+ channel: TarrableSearchPath,
+ dest: str) -> None:
+ v.status('Checking out corresponding git revision')
+ git = subprocess.Popen(['git',
+ '-C',
+ git_cachedir(channel.git_repo),
+ 'archive',
+ channel.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)
+
+
+def git_get_tarball(v: Verification, channel: TarrableSearchPath) -> str:
+ cache_file = tarball_cache_file(channel)
+ if os.path.exists(cache_file):
+ cached_tarball = open(cache_file).read(9999)
+ if os.path.exists(cached_tarball):
+ return cached_tarball
+
+ with tempfile.TemporaryDirectory() as output_dir:
+ output_filename = os.path.join(
+ output_dir, channel.release_name + '.tar.xz')
+ with open(output_filename, 'w') as output_file:
+ v.status(
+ 'Generating tarball for git revision %s' %
+ channel.git_revision)
+ git = subprocess.Popen(['git',
+ '-C',
+ git_cachedir(channel.git_repo),
+ 'archive',
+ '--prefix=%s/' % channel.release_name,
+ channel.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()
+
+ os.makedirs(os.path.dirname(cache_file), exist_ok=True)
+ open(cache_file, 'w').write(store_tarball)
+ return store_tarball # type: ignore # (for old mypy)
+
+
+def check_channel_metadata(
+ v: Verification,
+ channel: TarrableSearchPath,
+ channel_contents: str) -> None:
+ v.status('Verifying git commit in channel tarball')
+ v.result(
+ open(
+ os.path.join(
+ channel_contents,
+ channel.release_name,
+ '.git-revision')).read(999) == channel.git_revision)
+
+ v.status(
+ 'Verifying version-suffix is a suffix of release name %s:' %
+ channel.release_name)
+ version_suffix = open(
+ os.path.join(
+ channel_contents,
+ channel.release_name,
+ '.version-suffix')).read(999)
+ v.status(version_suffix)
+ v.result(channel.release_name.endswith(version_suffix))
+
+
+def check_channel_contents(
+ v: Verification,
+ channel: TarrableSearchPath) -> None:
+ with tempfile.TemporaryDirectory() as channel_contents, \
+ tempfile.TemporaryDirectory() as git_contents:
+
+ extract_tarball(v, channel, channel_contents)
+ check_channel_metadata(v, channel, channel_contents)
+
+ git_checkout(v, channel, git_contents)
+
+ compare_tarball_and_git(v, channel, channel_contents, git_contents)
+
+ v.status('Removing temporary directories')
+ v.ok()
+
+
+def pin_channel(v: Verification, channel: TarrableSearchPath) -> None:
+ fetch(v, channel)
+ parse_channel(v, channel)
+ fetch_resources(v, channel)
+ ensure_git_rev_available(v, channel)
+ check_channel_contents(v, channel)
+
+
+def git_revision_name(v: Verification, channel: TarrableSearchPath) -> str:
+ v.status('Getting commit date')
+ process = subprocess.run(['git',
+ '-C',
+ git_cachedir(channel.git_repo),
+ 'log',
+ '-n1',
+ '--format=%ct-%h',
+ '--abbrev=11',
+ '--no-show-signature',
+ channel.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())
+
+
+def read_search_path(conf: configparser.SectionProxy) -> SearchPath:
+ if 'alias_of' in conf:
+ return AliasSearchPath(**dict(conf.items()))
+ if 'channel_url' in conf:
+ return ChannelSearchPath(**dict(conf.items()))
+ return GitSearchPath(**dict(conf.items()))
+
+
+def read_config(filename: str) -> configparser.ConfigParser:
+ config = configparser.ConfigParser()
+ config.read_file(open(filename), filename)
+ return config
+
+
+def read_config_files(
+ filenames: Iterable[str]) -> Dict[str, configparser.SectionProxy]:
+ merged_config: Dict[str, configparser.SectionProxy] = {}
+ for file in filenames:
+ config = read_config(file)
+ for section in config.sections():
+ if section in merged_config:
+ raise Exception('Duplicate channel "%s"' % section)
+ merged_config[section] = config[section]
+ return merged_config
+
+
+def pin(args: argparse.Namespace) -> None:
v = Verification()
- info = fetch(v, 'https://channels.nixos.org/nixos-20.03')
- parse(v, info)
- fetch_resources(v, info)
- extract_channel(v, info)
- print(info)
+ config = read_config(args.channels_file)
+ for section in config.sections():
+ if args.channels and section not in args.channels:
+ continue
+ sp = read_search_path(config[section])
-main()
+ config[section].update(sp.pin(v)._asdict())
+
+ with open(args.channels_file, 'w') as configfile:
+ config.write(configfile)
+
+
+def update(args: argparse.Namespace) -> None:
+ v = Verification()
+ exprs: Dict[str, str] = {}
+ config = read_config_files(args.channels_file)
+ for section in config:
+ sp = read_search_path(config[section])
+ if isinstance(sp, AliasSearchPath):
+ assert 'git_repo' not in config[section]
+ continue
+ tarball = sp.fetch(v, section, config[section])
+ exprs[section] = (
+ 'f: f { name = "%s"; channelName = "%%s"; src = builtins.storePath "%s"; }' %
+ (config[section]['release_name'], tarball))
+
+ for section in config:
+ if 'alias_of' in config[section]:
+ exprs[section] = exprs[str(config[section]['alias_of'])]
+
+ command = [
+ 'nix-env',
+ '--profile',
+ '/nix/var/nix/profiles/per-user/%s/channels' %
+ getpass.getuser(),
+ '--show-trace',
+ '--file',
+ '<nix/unpack-channel.nix>',
+ '--install',
+ '--from-expression'] + [exprs[name] % name for name in sorted(exprs.keys())]
+ if args.dry_run:
+ print(' '.join(map(shlex.quote, command)))
+ else:
+ v.status('Installing channels with nix-env')
+ process = subprocess.run(command)
+ v.result(process.returncode == 0)
+
+
+def main() -> None:
+ parser = argparse.ArgumentParser(prog='pinch')
+ subparsers = parser.add_subparsers(dest='mode', required=True)
+ parser_pin = subparsers.add_parser('pin')
+ parser_pin.add_argument('channels_file', type=str)
+ parser_pin.add_argument('channels', type=str, nargs='*')
+ parser_pin.set_defaults(func=pin)
+ parser_update = subparsers.add_parser('update')
+ parser_update.add_argument('--dry-run', action='store_true')
+ parser_update.add_argument('channels_file', type=str, nargs='+')
+ parser_update.set_defaults(func=update)
+ args = parser.parse_args()
+ args.func(args)
+
+
+if __name__ == '__main__':
+ main()
projects / pinch / blobdiff