Aliases

[pinch] / pinch.py

diff --git a/pinch.py b/pinch.py
index e3b6882bb9fb1ffb6e08cd32c0363fb9b96251a8..b1471007f9399db512013a95a226210ef8cdf04c 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -1,10 +1,13 @@
+import argparse

 import configparser
 import filecmp
 import functools
 import configparser
 import filecmp
 import functools

+import getpass

 import hashlib
 import operator
 import os
 import os.path
 import hashlib
 import operator
 import os
 import os.path

+import shlex

 import shutil
 import subprocess
 import sys
 import shutil
 import subprocess
 import sys


@@ -35,13 +38,14 @@ class ChannelTableEntry(types.SimpleNamespace):
 
 
 class Channel(types.SimpleNamespace):
 
 
 class Channel(types.SimpleNamespace):

+    alias_of: str

     channel_html: bytes
     channel_url: str
     forwarded_url: str
     channel_html: bytes
     channel_url: str
     forwarded_url: str

-    git_cachedir: str

     git_ref: str
     git_repo: str
     git_revision: str
     git_ref: str
     git_repo: str
     git_revision: str

+    old_git_revision: str

     release_name: str
     table: Dict[str, ChannelTableEntry]
 
     release_name: str
     table: Dict[str, ChannelTableEntry]
 


@@ -56,7 +60,7 @@ class Verification:
         self.line_length = 0
 
     def status(self, s: str) -> None:
         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
         self.line_length += 1 + len(s)  # Unicode??
 
     @staticmethod


@@ -68,7 +72,7 @@ class Verification:
         length = len(message)
         cols = shutil.get_terminal_size().columns
         pad = (cols - (self.line_length + length)) % cols
         length = len(message)
         cols = shutil.get_terminal_size().columns
         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.line_length = 0
         if not r:
             raise VerificationError()


@@ -211,6 +215,40 @@ def fetch_resources(v: Verification, channel: Channel) -> None:
             channel.table['git-revision'].file).read(999) == channel.git_revision)
 
 
             channel.table['git-revision'].file).read(999) == channel.git_revision)
 
 

+def git_cachedir(git_repo: str) -> str:
+    # TODO: Consider using pyxdg to find this path.
+    return os.path.expanduser(
+        '~/.cache/pinch/git/%s' %
+        digest_string(
+            git_repo.encode()))
+
+
+def verify_git_ancestry(v: Verification, channel: Channel) -> 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: Channel) -> 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
 def git_fetch(v: Verification, channel: Channel) -> 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


@@ -218,51 +256,56 @@ def git_fetch(v: Verification, channel: Channel) -> None:
     # details for my comfort.  So we re-implement here half of nix.fetchGit.
     # :(
 
     # details for my comfort.  So we re-implement here half of nix.fetchGit.
     # :(
 

-    # TODO: Consider using pyxdg to find this path.
-    channel.git_cachedir = os.path.expanduser(
-        '~/.cache/nix-pin-channel/git/%s' %
-        digest_string(
-            channel.git_repo.encode()))
-    if not os.path.exists(channel.git_cachedir):
+    cachedir = git_cachedir(channel.git_repo)
+    if not os.path.exists(cachedir):

         v.status("Initializing git repo")
         process = subprocess.run(
         v.status("Initializing git repo")
         process = subprocess.run(

-            ['git', 'init', '--bare', channel.git_cachedir])
+            ['git', 'init', '--bare', cachedir])

         v.result(process.returncode == 0)
 
         v.result(process.returncode == 0)
 

-    v.status('Checking if we already have this rev:')
-    process = subprocess.run(
-        ['git', '-C', channel.git_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 == 1:
-        v.status('Fetching ref "%s"' % channel.git_ref)
-        # We don't use --force here because we want to abort and freak out if forced
-        # updates are happening.
-        process = subprocess.run(['git',
-                                  '-C',
-                                  channel.git_cachedir,
-                                  'fetch',
-                                  channel.git_repo,
-                                  '%s:%s' % (channel.git_ref,
-                                             channel.git_ref)])
-        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(
         v.status('Verifying that fetch retrieved this rev')
         process = subprocess.run(

-            ['git', '-C', channel.git_cachedir, 'cat-file', '-e', channel.git_revision])
+            ['git', '-C', cachedir, 'cat-file', '-e', channel.git_revision])

         v.result(process.returncode == 0)
         v.result(process.returncode == 0)

+    else:
+        channel.git_revision = open(
+            os.path.join(
+                cachedir,
+                'refs',
+                'heads',
+                channel.git_ref)).read(999).strip()

 
 

-    v.status('Verifying rev is an ancestor of ref')
-    process = subprocess.run(['git',
-                              '-C',
-                              channel.git_cachedir,
-                              'merge-base',
-                              '--is-ancestor',
-                              channel.git_revision,
-                              channel.git_ref])
-    v.result(process.returncode == 0)
+    verify_git_ancestry(v, channel)
+
+
+def ensure_git_rev_available(v: Verification, channel: Channel) -> 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(
 
 
 def compare_tarball_and_git(


@@ -311,7 +354,7 @@ def git_checkout(v: Verification, channel: Channel, dest: str) -> None:
     v.status('Checking out corresponding git revision')
     git = subprocess.Popen(['git',
                             '-C',
     v.status('Checking out corresponding git revision')
     git = subprocess.Popen(['git',
                             '-C',

-                            channel.git_cachedir,
+                            git_cachedir(channel.git_repo),

                             'archive',
                             channel.git_revision],
                            stdout=subprocess.PIPE)
                             'archive',
                             channel.git_revision],
                            stdout=subprocess.PIPE)


@@ -323,6 +366,33 @@ def git_checkout(v: Verification, channel: Channel, dest: str) -> None:
     v.result(git.returncode == 0 and tar.returncode == 0)
 
 
     v.result(git.returncode == 0 and tar.returncode == 0)
 
 

+def git_get_tarball(v: Verification, channel: Channel) -> str:
+    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], capture_output=True)
+        v.result(process.returncode == 0)
+        return process.stdout.decode().strip()
+
+

 def check_channel_metadata(
         v: Verification,
         channel: Channel,
 def check_channel_metadata(
         v: Verification,
         channel: Channel,


@@ -362,22 +432,121 @@ def check_channel_contents(v: Verification, channel: Channel) -> None:
     v.ok()
 
 
     v.ok()
 
 

-def main(argv: List[str]) -> None:
+def pin_channel(v: Verification, channel: Channel) -> 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: Channel) -> str:
+    v.status('Getting commit date')
+    process = subprocess.run(['git',
+                              '-C',
+                              git_cachedir(channel.git_repo),
+                              'lo',
+                              '-n1',
+                              '--format=%ct-%h',
+                              '--abbrev=11',
+                              channel.git_revision],
+                             capture_output=True)
+    v.result(process.returncode == 0 and process.stdout != '')
+    return '%s-%s' % (os.path.basename(channel.git_repo),
+                      process.stdout.decode().strip())
+
+
+def pin(args: argparse.Namespace) -> None:

     v = Verification()
     config = configparser.ConfigParser()
     v = Verification()
     config = configparser.ConfigParser()

-    config.read_file(open(argv[1]), argv[1])
+    config.read_file(open(args.channels_file), args.channels_file)

     for section in config.sections():
     for section in config.sections():

+        if args.channels and section not in args.channels:
+            continue
+

         channel = Channel(**dict(config[section].items()))
         channel = Channel(**dict(config[section].items()))

-        fetch(v, channel)
-        parse_channel(v, channel)
-        fetch_resources(v, channel)
-        git_fetch(v, channel)
-        check_channel_contents(v, channel)
-        config[section]['git_rev'] = channel.git_revision
-        config[section]['tarball_url'] = channel.table['nixexprs.tar.xz'].absolute_url
-        config[section]['tarball_sha256'] = channel.table['nixexprs.tar.xz'].digest
-    with open(argv[1], 'w') as configfile:
+
+        if hasattr(channel, 'alias_of'):
+            assert not hasattr(channel, 'git_repo')
+            continue
+
+        if hasattr(channel, 'git_revision'):
+            channel.old_git_revision = channel.git_revision
+            del channel.git_revision
+
+        if 'channel_url' in config[section]:
+            pin_channel(v, channel)
+            config[section]['release_name'] = channel.release_name
+            config[section]['tarball_url'] = channel.table['nixexprs.tar.xz'].absolute_url
+            config[section]['tarball_sha256'] = channel.table['nixexprs.tar.xz'].digest
+        else:
+            git_fetch(v, channel)
+            config[section]['release_name'] = git_revision_name(v, channel)
+        config[section]['git_revision'] = channel.git_revision
+
+    with open(args.channels_file, 'w') as configfile:

         config.write(configfile)
 
 
         config.write(configfile)
 
 

-main(sys.argv)
+def update(args: argparse.Namespace) -> None:
+    v = Verification()
+    config = configparser.ConfigParser()
+    config.read_file(open(args.channels_file), args.channels_file)
+    exprs = {}
+    for section in config.sections():
+
+        if 'alias_of' in config[section]:
+            assert 'git_repo' not in config[section]
+            continue
+
+        if 'channel_url' in config[section]:
+            tarball = fetch_with_nix_prefetch_url(
+                v, config[section]['tarball_url'], Digest16(
+                    config[section]['tarball_sha256']))
+        else:
+            channel = Channel(**dict(config[section].items()))
+            ensure_git_rev_available(v, channel)
+            tarball = git_get_tarball(v, channel)
+
+        exprs[section] = (
+            'f: f { name = "%s"; channelName = "%%s"; src = builtins.storePath "%s"; }' %
+            (config[section]['release_name'], tarball))
+
+    for section in config.sections():
+        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)
+    parser_update.set_defaults(func=update)
+    args = parser.parse_args()
+    args.func(args)
+
+
+main()