fetch_resource is just for Channels

[pinch] / pinch.py

diff --git a/pinch.py b/pinch.py
index bfc6ac635dfd0866e8cae54d56ac4a9c1daae44f..d8bf75cf3747f44f9b0547b0db72d631166775da 100644 (file)
--- a/pinch.py
+++ b/pinch.py
@@ -22,8 +22,12 @@ from typing import (
     Dict,
     Iterable,
     List,
     Dict,
     Iterable,
     List,

+    Mapping,
+    NamedTuple,

     NewType,
     Tuple,
     NewType,
     Tuple,

+    Type,
+    Union,

 )
 
 # Use xdg module when it's less painful to have as a dependency
 )
 
 # Use xdg module when it's less painful to have as a dependency


@@ -86,45 +90,61 @@ class ChannelTableEntry(types.SimpleNamespace):
     url: str
 
 
     url: str
 
 

-class SearchPath(types.SimpleNamespace, ABC):
+class AliasPin(NamedTuple):
+    pass
+
+
+class GitPin(NamedTuple):
+    git_revision: str

     release_name: 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
     @abstractmethod

-    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+    def pin(self, v: Verification) -> Pin:

         pass
 
 
 class AliasSearchPath(SearchPath):
     alias_of: str
 
         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')
         assert not hasattr(self, 'git_repo')

+        return AliasPin()

 
 
 
 

-class Channel(SearchPath):
+# (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
     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]
 
     old_git_revision: str
     table: Dict[str, ChannelTableEntry]
 

-    def pin(self, v: Verification, conf: configparser.SectionProxy) -> None:
+
+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
 
         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
+        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:
 
     def fetch(self, v: Verification, section: str,
               conf: configparser.SectionProxy) -> str:


@@ -133,15 +153,41 @@ class Channel(SearchPath):
                 'Cannot update unpinned channel "%s" (Run "pin" before "update")' %
                 section)
 
                 '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)
 
 
         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
+
+        fetch(v, self)
+        parse_channel(v, self)
+        fetch_resources(v, self)
+        ensure_git_rev_available(v, self)
+        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
+    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:
 def compare(a: str, b: str) -> Tuple[List[str], List[str], List[str]]:
 
     def throw(error: OSError) -> None:


@@ -170,7 +216,7 @@ def compare(a: str, b: str) -> Tuple[List[str], List[str], List[str]]:
     return filecmp.cmpfiles(a, b, files, shallow=False)
 
 
     return filecmp.cmpfiles(a, b, files, shallow=False)
 
 

-def fetch(v: Verification, channel: Channel) -> None:
+def fetch(v: Verification, channel: TarrableSearchPath) -> None:

     v.status('Fetching channel')
     request = urllib.request.urlopen(channel.channel_url, timeout=10)
     channel.channel_html = request.read()
     v.status('Fetching channel')
     request = urllib.request.urlopen(channel.channel_url, timeout=10)
     channel.channel_html = request.read()


@@ -179,7 +225,7 @@ def fetch(v: Verification, channel: Channel) -> None:
     v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
 
 
     v.check('Got forwarded', channel.channel_url != channel.forwarded_url)
 
 

-def parse_channel(v: Verification, channel: Channel) -> None:
+def parse_channel(v: Verification, channel: TarrableSearchPath) -> None:

     v.status('Parsing channel description as XML')
     d = xml.dom.minidom.parseString(channel.channel_html)
     v.ok()
     v.status('Parsing channel description as XML')
     d = xml.dom.minidom.parseString(channel.channel_html)
     v.ok()


@@ -259,7 +305,7 @@ def fetch_with_nix_prefetch_url(
     return path  # type: ignore  # (for old mypy)
 
 
     return path  # type: ignore  # (for old mypy)
 
 

-def fetch_resources(v: Verification, channel: Channel) -> None:
+def fetch_resources(v: Verification, channel: ChannelSearchPath) -> None:

     for resource in ['git-revision', 'nixexprs.tar.xz']:
         fields = channel.table[resource]
         fields.absolute_url = urllib.parse.urljoin(
     for resource in ['git-revision', 'nixexprs.tar.xz']:
         fields = channel.table[resource]
         fields.absolute_url = urllib.parse.urljoin(


@@ -279,7 +325,7 @@ def git_cachedir(git_repo: str) -> str:
         digest_string(git_repo.encode()))
 
 
         digest_string(git_repo.encode()))
 
 

-def tarball_cache_file(channel: Channel) -> str:
+def tarball_cache_file(channel: TarrableSearchPath) -> str:

     return os.path.join(
         xdg.XDG_CACHE_HOME,
         'pinch/git-tarball',
     return os.path.join(
         xdg.XDG_CACHE_HOME,
         'pinch/git-tarball',


@@ -289,7 +335,7 @@ def tarball_cache_file(channel: Channel) -> str:
          channel.release_name))
 
 
          channel.release_name))
 
 

-def verify_git_ancestry(v: Verification, channel: Channel) -> None:
+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',
     cachedir = git_cachedir(channel.git_repo)
     v.status('Verifying rev is an ancestor of ref')
     process = subprocess.run(['git',


@@ -315,7 +361,7 @@ def verify_git_ancestry(v: Verification, channel: Channel) -> None:
         v.result(process.returncode == 0)
 
 
         v.result(process.returncode == 0)
 
 

-def git_fetch(v: Verification, channel: Channel) -> None:
+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
     # 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


@@ -357,7 +403,9 @@ def git_fetch(v: Verification, channel: Channel) -> None:
     verify_git_ancestry(v, channel)
 
 
     verify_git_ancestry(v, channel)
 
 

-def ensure_git_rev_available(v: Verification, channel: Channel) -> None:
+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:')
     cachedir = git_cachedir(channel.git_repo)
     if os.path.exists(cachedir):
         v.status('Checking if we already have this rev:')


@@ -376,7 +424,7 @@ def ensure_git_rev_available(v: Verification, channel: Channel) -> None:
 
 def compare_tarball_and_git(
         v: Verification,
 
 def compare_tarball_and_git(
         v: Verification,

-        channel: Channel,
+        channel: TarrableSearchPath,

         channel_contents: str,
         git_contents: str) -> None:
     v.status('Comparing channel tarball with git checkout')
         channel_contents: str,
         git_contents: str) -> None:
     v.status('Comparing channel tarball with git checkout')


@@ -407,7 +455,10 @@ def compare_tarball_and_git(
         len(benign_errors) == len(expected_errors))
 
 
         len(benign_errors) == len(expected_errors))
 
 

-def extract_tarball(v: Verification, channel: Channel, dest: str) -> None:
+def extract_tarball(
+        v: Verification,
+        channel: TarrableSearchPath,
+        dest: str) -> None:

     v.status('Extracting tarball %s' %
              channel.table['nixexprs.tar.xz'].file)
     shutil.unpack_archive(
     v.status('Extracting tarball %s' %
              channel.table['nixexprs.tar.xz'].file)
     shutil.unpack_archive(


@@ -416,7 +467,10 @@ def extract_tarball(v: Verification, channel: Channel, dest: str) -> None:
     v.ok()
 
 
     v.ok()
 
 

-def git_checkout(v: Verification, channel: Channel, dest: str) -> None:
+def git_checkout(
+        v: Verification,
+        channel: TarrableSearchPath,
+        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',


@@ -433,7 +487,7 @@ 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:
+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)
     cache_file = tarball_cache_file(channel)
     if os.path.exists(cache_file):
         cached_tarball = open(cache_file).read(9999)


@@ -472,7 +526,7 @@ def git_get_tarball(v: Verification, channel: Channel) -> str:
 
 def check_channel_metadata(
         v: Verification,
 
 def check_channel_metadata(
         v: Verification,

-        channel: Channel,
+        channel: TarrableSearchPath,

         channel_contents: str) -> None:
     v.status('Verifying git commit in channel tarball')
     v.result(
         channel_contents: str) -> None:
     v.status('Verifying git commit in channel tarball')
     v.result(


@@ -494,7 +548,9 @@ def check_channel_metadata(
     v.result(channel.release_name.endswith(version_suffix))
 
 
     v.result(channel.release_name.endswith(version_suffix))
 
 

-def check_channel_contents(v: Verification, channel: Channel) -> None:
+def check_channel_contents(
+        v: Verification,
+        channel: TarrableSearchPath) -> None:

     with tempfile.TemporaryDirectory() as channel_contents, \
             tempfile.TemporaryDirectory() as git_contents:
 
     with tempfile.TemporaryDirectory() as channel_contents, \
             tempfile.TemporaryDirectory() as git_contents:
 


@@ -509,15 +565,7 @@ def check_channel_contents(v: Verification, channel: Channel) -> None:
     v.ok()
 
 
     v.ok()
 
 

-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:
+def git_revision_name(v: Verification, channel: TarrableSearchPath) -> str:

     v.status('Getting commit date')
     process = subprocess.run(['git',
                               '-C',
     v.status('Getting commit date')
     process = subprocess.run(['git',
                               '-C',


@@ -535,9 +583,12 @@ def git_revision_name(v: Verification, channel: Channel) -> str:
 
 
 def read_search_path(conf: configparser.SectionProxy) -> SearchPath:
 
 
 def read_search_path(conf: configparser.SectionProxy) -> SearchPath:

-    if 'alias_of' in conf:
-        return AliasSearchPath(**dict(conf.items()))
-    return Channel(**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:
 
 
 def read_config(filename: str) -> configparser.ConfigParser:


@@ -567,7 +618,7 @@ def pin(args: argparse.Namespace) -> None:
 
         sp = read_search_path(config[section])
 
 
         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)
 
     with open(args.channels_file, 'w') as configfile:
         config.write(configfile)