]> git.scottworley.com Git - pinch/blobdiff - pinch.py
Duplicate searchpath checking in one place
[pinch] / pinch.py
index b1471007f9399db512013a95a226210ef8cdf04c..26982260cc62c5f485175c6ee77e84868909a0a5 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -25,29 +25,17 @@ from typing import (
     Tuple,
 )
 
-Digest16 = NewType('Digest16', str)
-Digest32 = NewType('Digest32', str)
+# Use xdg module when it's less painful to have as a dependency
 
 
-class ChannelTableEntry(types.SimpleNamespace):
-    absolute_url: str
-    digest: Digest16
-    file: str
-    size: int
-    url: str
+class XDG(types.SimpleNamespace):
+    XDG_CACHE_HOME: str
 
 
-class Channel(types.SimpleNamespace):
-    alias_of: str
-    channel_html: bytes
-    channel_url: str
-    forwarded_url: str
-    git_ref: str
-    git_repo: str
-    git_revision: str
-    old_git_revision: str
-    release_name: str
-    table: Dict[str, ChannelTableEntry]
+xdg = XDG(
+    XDG_CACHE_HOME=os.getenv(
+        'XDG_CACHE_HOME',
+        os.path.expanduser('~/.cache')))
 
 
 class VerificationError(Exception):
@@ -70,7 +58,7 @@ class Verification:
     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), file=sys.stderr)
         self.line_length = 0
@@ -85,6 +73,68 @@ class Verification:
         self.result(True)
 
 
+Digest16 = NewType('Digest16', str)
+Digest32 = NewType('Digest32', str)
+
+
+class ChannelTableEntry(types.SimpleNamespace):
+    absolute_url: str
+    digest: Digest16
+    file: str
+    size: int
+    url: str
+
+
+class SearchPath(types.SimpleNamespace):
+    release_name: str
+
+
+class Channel(SearchPath):
+    alias_of: str
+    channel_html: bytes
+    channel_url: str
+    forwarded_url: str
+    git_ref: str
+    git_repo: str
+    git_revision: str
+    old_git_revision: str
+    table: Dict[str, ChannelTableEntry]
+
+    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+        if hasattr(self, 'alias_of'):
+            assert not hasattr(self, 'git_repo')
+            return
+
+        if hasattr(self, 'git_revision'):
+            self.old_git_revision = self.git_revision
+            del self.git_revision
+
+        if 'channel_url' in conf:
+            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
+        else:
+            git_fetch(v, self)
+            conf['release_name'] = git_revision_name(v, self)
+        conf['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)
+
+        if 'channel_url' in conf:
+            return fetch_with_nix_prefetch_url(
+                v, conf['tarball_url'], Digest16(
+                    conf['tarball_sha256']))
+
+        ensure_git_rev_available(v, self)
+        return git_get_tarball(v, self)
+
+
 def compare(a: str, b: str) -> Tuple[List[str], List[str], List[str]]:
 
     def throw(error: OSError) -> None:
@@ -118,7 +168,7 @@ def fetch(v: Verification, channel: Channel) -> None:
     request = urllib.request.urlopen(channel.channel_url, timeout=10)
     channel.channel_html = request.read()
     channel.forwarded_url = request.geturl()
-    v.result(request.status == 200)
+    v.result(request.status == 200)  # type: ignore  # (for old mypy)
     v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
 
 
@@ -171,7 +221,7 @@ def digest_file(filename: str) -> Digest16:
 def to_Digest16(v: Verification, digest32: Digest32) -> Digest16:
     v.status('Converting digest to base16')
     process = subprocess.run(
-        ['nix', 'to-base16', '--type', 'sha256', digest32], capture_output=True)
+        ['nix', 'to-base16', '--type', 'sha256', digest32], stdout=subprocess.PIPE)
     v.result(process.returncode == 0)
     return Digest16(process.stdout.decode().strip())
 
@@ -179,7 +229,7 @@ def to_Digest16(v: Verification, digest32: Digest32) -> Digest16:
 def to_Digest32(v: Verification, digest16: Digest16) -> Digest32:
     v.status('Converting digest to base32')
     process = subprocess.run(
-        ['nix', 'to-base32', '--type', 'sha256', digest16], capture_output=True)
+        ['nix', 'to-base32', '--type', 'sha256', digest16], stdout=subprocess.PIPE)
     v.result(process.returncode == 0)
     return Digest32(process.stdout.decode().strip())
 
@@ -190,7 +240,7 @@ def fetch_with_nix_prefetch_url(
         digest: Digest16) -> str:
     v.status('Fetching %s' % url)
     process = subprocess.run(
-        ['nix-prefetch-url', '--print-path', url, digest], capture_output=True)
+        ['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 == ''
@@ -199,7 +249,7 @@ def fetch_with_nix_prefetch_url(
     v.status("Verifying file digest")
     file_digest = digest_file(path)
     v.result(file_digest == digest)
-    return path
+    return path  # type: ignore  # (for old mypy)
 
 
 def fetch_resources(v: Verification, channel: Channel) -> None:
@@ -216,11 +266,20 @@ def fetch_resources(v: Verification, channel: Channel) -> None:
 
 
 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()))
+    return os.path.join(
+        xdg.XDG_CACHE_HOME,
+        'pinch/git',
+        digest_string(git_repo.encode()))
+
+
+def tarball_cache_file(channel: Channel) -> 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: Channel) -> None:
@@ -360,13 +419,20 @@ def git_checkout(v: Verification, channel: Channel, dest: str) -> None:
                            stdout=subprocess.PIPE)
     tar = subprocess.Popen(
         ['tar', 'x', '-C', dest, '-f', '-'], stdin=git.stdout)
-    git.stdout.close()
+    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: Channel) -> 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')
@@ -388,9 +454,13 @@ def git_get_tarball(v: Verification, channel: Channel) -> str:
 
         v.status('Putting tarball in Nix store')
         process = subprocess.run(
-            ['nix-store', '--add', output_filename], capture_output=True)
+            ['nix-store', '--add', output_filename], stdout=subprocess.PIPE)
         v.result(process.returncode == 0)
-        return process.stdout.decode().strip()
+        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(
@@ -445,44 +515,50 @@ def git_revision_name(v: Verification, channel: Channel) -> str:
     process = subprocess.run(['git',
                               '-C',
                               git_cachedir(channel.git_repo),
-                              'lo',
+                              'log',
                               '-n1',
                               '--format=%ct-%h',
                               '--abbrev=11',
+                              '--no-show-signature',
                               channel.git_revision],
-                             capture_output=True)
-    v.result(process.returncode == 0 and process.stdout != '')
+                             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:
+    return Channel(**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()
-    config = configparser.ConfigParser()
-    config.read_file(open(args.channels_file), args.channels_file)
+    config = read_config(args.channels_file)
     for section in config.sections():
         if args.channels and section not in args.channels:
             continue
 
-        channel = Channel(**dict(config[section].items()))
-
-        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
+        sp = read_search_path(config[section])
 
-        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
+        sp.pin(v, config[section])
 
     with open(args.channels_file, 'w') as configfile:
         config.write(configfile)
@@ -490,29 +566,19 @@ def pin(args: argparse.Namespace) -> None:
 
 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():
-
+    exprs: Dict[str, str] = {}
+    config = read_config_files(args.channels_file)
+    for section in config:
         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)
-
+        sp = read_search_path(config[section])
+        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.sections():
+    for section in config:
         if 'alias_of' in config[section]:
             exprs[section] = exprs[str(config[section]['alias_of'])]
 
@@ -543,10 +609,11 @@ def main() -> None:
     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.add_argument('channels_file', type=str, nargs='+')
     parser_update.set_defaults(func=update)
     args = parser.parse_args()
     args.func(args)
 
 
-main()
+if __name__ == '__main__':
+    main()