]> git.scottworley.com Git - pinch/blobdiff - pinch.py
Continue pulling release_name and git_revision out of SearchPath
[pinch] / pinch.py
index 58f7a3290cc507760303858cd90ba351f118d0e0..1b11709901e79825fe98a3e9bb10699be374db9d 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -22,8 +22,13 @@ from typing import (
     Dict,
     Iterable,
     List,
+    Mapping,
+    NamedTuple,
     NewType,
+    Optional,
     Tuple,
+    Type,
+    Union,
 )
 
 # Use xdg module when it's less painful to have as a dependency
@@ -86,19 +91,38 @@ class ChannelTableEntry(types.SimpleNamespace):
     url: str
 
 
-class SearchPath(types.SimpleNamespace, ABC):
+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, conf: configparser.SectionProxy) -> None:
+    def pin(self, v: Verification) -> Pin:
         pass
 
 
 class AliasSearchPath(SearchPath):
     alias_of: str
 
-    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+    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
@@ -109,43 +133,51 @@ class TarrableSearchPath(SearchPath, ABC):  # pylint: disable=abstract-method
     forwarded_url: str
     git_ref: str
     git_repo: str
-    git_revision: str
-    old_git_revision: str
     table: Dict[str, ChannelTableEntry]
 
 
 class GitSearchPath(TarrableSearchPath):
-    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+    def pin(self, v: Verification) -> GitPin:
+        old_revision = (
+            self.git_revision if hasattr(self, 'git_revision') else None)
         if hasattr(self, 'git_revision'):
-            self.old_git_revision = self.git_revision
             del self.git_revision
 
-        git_fetch(v, self)
-        conf['release_name'] = git_revision_name(v, self)
-        conf['git_revision'] = self.git_revision
+        new_revision = git_fetch(v, self, None, old_revision)
+        return GitPin(release_name=git_revision_name(v, self, new_revision),
+                      git_revision=new_revision)
 
     def fetch(self, v: Verification, section: str,
               conf: configparser.SectionProxy) -> str:
-        if 'git_repo' not in conf or 'release_name' not in conf:
+        if 'git_revision' not in conf or 'release_name' not in conf:
             raise Exception(
                 'Cannot update unpinned channel "%s" (Run "pin" before "update")' %
                 section)
+        the_pin = GitPin(
+            release_name=conf['release_name'],
+            git_revision=conf['git_revision'])
 
-        ensure_git_rev_available(v, self)
-        return git_get_tarball(v, self)
+        ensure_git_rev_available(v, self, the_pin, None)
+        return git_get_tarball(v, self, the_pin)
 
 
 class ChannelSearchPath(TarrableSearchPath):
-    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+    def pin(self, v: Verification) -> ChannelPin:
+        old_revision = (
+            self.git_revision if hasattr(self, 'git_revision') else None)
         if hasattr(self, 'git_revision'):
-            self.old_git_revision = self.git_revision
             del self.git_revision
 
-        pin_channel(v, self)
-        conf['release_name'] = self.release_name
-        conf['tarball_url'] = self.table['nixexprs.tar.xz'].absolute_url
-        conf['tarball_sha256'] = self.table['nixexprs.tar.xz'].digest
-        conf['git_revision'] = self.git_revision
+        fetch(v, self)
+        new_gitpin = parse_channel(v, self)
+        fetch_resources(v, self, new_gitpin)
+        ensure_git_rev_available(v, self, new_gitpin, old_revision)
+        check_channel_contents(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
@@ -198,7 +230,7 @@ def fetch(v: Verification, channel: TarrableSearchPath) -> None:
     v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
 
 
-def parse_channel(v: Verification, channel: TarrableSearchPath) -> None:
+def parse_channel(v: Verification, channel: TarrableSearchPath) -> GitPin:
     v.status('Parsing channel description as XML')
     d = xml.dom.minidom.parseString(channel.channel_html)
     v.ok()
@@ -229,6 +261,7 @@ def parse_channel(v: Verification, channel: TarrableSearchPath) -> None:
         channel.table[name] = ChannelTableEntry(
             url=url, digest=digest, size=size)
     v.ok()
+    return GitPin(release_name=title_name, git_revision=channel.git_revision)
 
 
 def digest_string(s: bytes) -> Digest16:
@@ -278,7 +311,10 @@ def fetch_with_nix_prefetch_url(
     return path  # type: ignore  # (for old mypy)
 
 
-def fetch_resources(v: Verification, channel: TarrableSearchPath) -> None:
+def fetch_resources(
+        v: Verification,
+        channel: ChannelSearchPath,
+        pin: GitPin) -> None:
     for resource in ['git-revision', 'nixexprs.tar.xz']:
         fields = channel.table[resource]
         fields.absolute_url = urllib.parse.urljoin(
@@ -288,7 +324,7 @@ def fetch_resources(v: Verification, channel: TarrableSearchPath) -> None:
     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)
+            channel.table['git-revision'].file).read(999) == pin.git_revision)
 
 
 def git_cachedir(git_repo: str) -> str:
@@ -308,7 +344,11 @@ def tarball_cache_file(channel: TarrableSearchPath) -> str:
          channel.release_name))
 
 
-def verify_git_ancestry(v: Verification, channel: TarrableSearchPath) -> None:
+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')
     process = subprocess.run(['git',
@@ -316,25 +356,29 @@ def verify_git_ancestry(v: Verification, channel: TarrableSearchPath) -> None:
                               cachedir,
                               'merge-base',
                               '--is-ancestor',
-                              channel.git_revision,
+                              new_revision,
                               channel.git_ref])
     v.result(process.returncode == 0)
 
-    if hasattr(channel, 'old_git_revision'):
+    if old_revision is not None:
         v.status(
             'Verifying rev is an ancestor of previous rev %s' %
-            channel.old_git_revision)
+            old_revision)
         process = subprocess.run(['git',
                                   '-C',
                                   cachedir,
                                   'merge-base',
                                   '--is-ancestor',
-                                  channel.old_git_revision,
-                                  channel.git_revision])
+                                  old_revision,
+                                  new_revision])
         v.result(process.returncode == 0)
 
 
-def git_fetch(v: Verification, channel: TarrableSearchPath) -> None:
+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
@@ -360,39 +404,43 @@ def git_fetch(v: Verification, channel: TarrableSearchPath) -> None:
                                          channel.git_ref)])
     v.result(process.returncode == 0)
 
-    if hasattr(channel, 'git_revision'):
+    if desired_revision is not None:
         v.status('Verifying that fetch retrieved this rev')
         process = subprocess.run(
-            ['git', '-C', cachedir, 'cat-file', '-e', channel.git_revision])
+            ['git', '-C', cachedir, 'cat-file', '-e', desired_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)
+    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) -> None:
+        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', channel.git_revision])
+            ['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)
+            verify_git_ancestry(v, channel, pin.git_revision, old_revision)
             return
-    git_fetch(v, channel)
+    git_fetch(v, channel, pin.git_revision, old_revision)
 
 
 def compare_tarball_and_git(
@@ -460,7 +508,10 @@ def git_checkout(
     v.result(git.returncode == 0 and tar.returncode == 0)
 
 
-def git_get_tarball(v: Verification, channel: TarrableSearchPath) -> str:
+def git_get_tarball(
+        v: Verification,
+        channel: TarrableSearchPath,
+        pin: GitPin) -> str:
     cache_file = tarball_cache_file(channel)
     if os.path.exists(cache_file):
         cached_tarball = open(cache_file).read(9999)
@@ -469,17 +520,17 @@ def git_get_tarball(v: Verification, channel: TarrableSearchPath) -> str:
 
     with tempfile.TemporaryDirectory() as output_dir:
         output_filename = os.path.join(
-            output_dir, channel.release_name + '.tar.xz')
+            output_dir, pin.release_name + '.tar.xz')
         with open(output_filename, 'w') as output_file:
             v.status(
                 'Generating tarball for git revision %s' %
-                channel.git_revision)
+                pin.git_revision)
             git = subprocess.Popen(['git',
                                     '-C',
                                     git_cachedir(channel.git_repo),
                                     'archive',
-                                    '--prefix=%s/' % channel.release_name,
-                                    channel.git_revision],
+                                    '--prefix=%s/' % pin.release_name,
+                                    pin.git_revision],
                                    stdout=subprocess.PIPE)
             xz = subprocess.Popen(['xz'], stdin=git.stdout, stdout=output_file)
             xz.wait()
@@ -538,15 +589,10 @@ def check_channel_contents(
     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:
+def git_revision_name(
+        v: Verification,
+        channel: TarrableSearchPath,
+        git_revision: str) -> str:
     v.status('Getting commit date')
     process = subprocess.run(['git',
                               '-C',
@@ -556,7 +602,7 @@ def git_revision_name(v: Verification, channel: TarrableSearchPath) -> str:
                               '--format=%ct-%h',
                               '--abbrev=11',
                               '--no-show-signature',
-                              channel.git_revision],
+                              git_revision],
                              stdout=subprocess.PIPE)
     v.result(process.returncode == 0 and process.stdout != b'')
     return '%s-%s' % (os.path.basename(channel.git_repo),
@@ -564,11 +610,12 @@ def git_revision_name(v: Verification, channel: TarrableSearchPath) -> str:
 
 
 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()))
+    mapping: Mapping[str, Type[SearchPath]] = {
+        'alias': AliasSearchPath,
+        'channel': ChannelSearchPath,
+        'git': GitSearchPath,
+    }
+    return mapping[conf['type']](**dict(conf.items()))
 
 
 def read_config(filename: str) -> configparser.ConfigParser:
@@ -589,7 +636,7 @@ def read_config_files(
     return merged_config
 
 
-def pin(args: argparse.Namespace) -> None:
+def pinCommand(args: argparse.Namespace) -> None:
     v = Verification()
     config = read_config(args.channels_file)
     for section in config.sections():
@@ -598,13 +645,13 @@ def pin(args: argparse.Namespace) -> None:
 
         sp = read_search_path(config[section])
 
-        sp.pin(v, config[section])
+        config[section].update(sp.pin(v)._asdict())
 
     with open(args.channels_file, 'w') as configfile:
         config.write(configfile)
 
 
-def update(args: argparse.Namespace) -> None:
+def updateCommand(args: argparse.Namespace) -> None:
     v = Verification()
     exprs: Dict[str, str] = {}
     config = read_config_files(args.channels_file)
@@ -646,11 +693,11 @@ def main() -> None:
     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_pin.set_defaults(func=pinCommand)
     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)
+    parser_update.set_defaults(func=updateCommand)
     args = parser.parse_args()
     args.func(args)