Formatting

[pinch] / pinch.py

diff --git a/pinch.py b/pinch.py
index dd707180d0ff474a2af30d649a98a44c80be32ca..b3f65c69b9f8c9a943f150c3d99b61e90e465fa5 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -36,14 +36,15 @@ class ChannelTableEntry(types.SimpleNamespace):
 
 class Channel(types.SimpleNamespace):
     channel_html: bytes
+    channel_url: str
     forwarded_url: str
     git_cachedir: str
     git_ref: str
     git_repo: str
     git_revision: str
+    old_git_revision: str
     release_name: str
     table: Dict[str, ChannelTableEntry]
-    url: str
 
 
 class VerificationError(Exception):
@@ -111,11 +112,11 @@ def compare(a: str, b: str) -> Tuple[List[str], List[str], List[str]]:
 
 def fetch(v: Verification, channel: Channel) -> None:
     v.status('Fetching channel')
-    request = urllib.request.urlopen(channel.url, timeout=10)
+    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.check('Got forwarded', channel.url != channel.forwarded_url)
+    v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
 
 
 def parse_channel(v: Verification, channel: Channel) -> None:
@@ -222,23 +223,29 @@ def git_fetch(v: Verification, channel: Channel) -> None:
     channel.git_cachedir = os.path.expanduser(
         '~/.cache/nix-pin-channel/git/%s' %
         digest_string(
-            channel.url.encode()))
+            channel.git_repo.encode()))
     if not os.path.exists(channel.git_cachedir):
         v.status("Initializing git repo")
         process = subprocess.run(
             ['git', 'init', '--bare', channel.git_cachedir])
         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)
+    have_rev = False
+    if hasattr(channel, 'git_revision'):
+        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)
+        have_rev = process.returncode == 0
+
+    if not have_rev:
+        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',
@@ -249,10 +256,19 @@ def git_fetch(v: Verification, channel: Channel) -> None:
                                   '%s:%s' % (channel.git_ref,
                                              channel.git_ref)])
         v.result(process.returncode == 0)
-        v.status('Verifying that fetch retrieved this rev')
-        process = subprocess.run(
-            ['git', '-C', channel.git_cachedir, 'cat-file', '-e', channel.git_revision])
-        v.result(process.returncode == 0)
+        if hasattr(channel, 'git_revision'):
+            v.status('Verifying that fetch retrieved this rev')
+            process = subprocess.run(
+                ['git', '-C', channel.git_cachedir, 'cat-file', '-e', channel.git_revision])
+            v.result(process.returncode == 0)
+
+    if not hasattr(channel, 'git_revision'):
+        channel.git_revision = open(
+            os.path.join(
+                channel.git_cachedir,
+                'refs',
+                'heads',
+                channel.git_ref)).read(999).strip()
 
     v.status('Verifying rev is an ancestor of ref')
     process = subprocess.run(['git',
@@ -264,6 +280,19 @@ def git_fetch(v: Verification, channel: Channel) -> None:
                               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',
+                                  channel.git_cachedir,
+                                  'merge-base',
+                                  '--is-ancestor',
+                                  channel.old_git_revision,
+                                  channel.git_revision])
+        v.result(process.returncode == 0)
+
 
 def compare_tarball_and_git(
         v: Verification,
@@ -362,20 +391,36 @@ def check_channel_contents(v: Verification, channel: Channel) -> None:
     v.ok()
 
 
+def pin_channel(v: Verification, channel: Channel) -> None:
+    fetch(v, channel)
+    parse_channel(v, channel)
+    fetch_resources(v, channel)
+    git_fetch(v, channel)
+    check_channel_contents(v, channel)
+
+
+def make_channel(conf: configparser.SectionProxy) -> Channel:
+    channel = Channel(**dict(conf.items()))
+    if hasattr(channel, 'git_revision'):
+        channel.old_git_revision = channel.git_revision
+        del channel.git_revision
+    return channel
+
+
 def main(argv: List[str]) -> None:
     v = Verification()
     config = configparser.ConfigParser()
     config.read_file(open(argv[1]), argv[1])
     for section in config.sections():
-        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
+        channel = make_channel(config[section])
+        if 'channel_url' in config[section]:
+            pin_channel(v, channel)
+            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]['git_revision'] = channel.git_revision
+
     with open(argv[1], 'w') as configfile:
         config.write(configfile)