From 736c25ebc1f9814c84429ed9dd16cd23104576f5 Mon Sep 17 00:00:00 2001
From: Scott Worley <scottworley@scottworley.com>
Date: Fri, 10 Apr 2020 16:40:01 -0700
Subject: [PATCH] Update channels from pins

---
 pinch.py | 83 ++++++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 72 insertions(+), 11 deletions(-)

diff --git a/pinch.py b/pinch.py
index 0f8f00a..5bb4e95 100644
--- a/pinch.py
+++ b/pinch.py
@@ -2,6 +2,7 @@ import argparse
 import configparser
 import filecmp
 import functools
+import getpass
 import hashlib
 import operator
 import os
@@ -362,6 +363,33 @@ def git_checkout(v: Verification, channel: Channel, dest: str) -> None:
     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,
@@ -425,40 +453,73 @@ def git_revision_name(v: Verification, channel: Channel) -> str:
                       process.stdout.decode().strip())
 
 
-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 pin(args: argparse.Namespace) -> None:
     v = Verification()
     config = configparser.ConfigParser()
     config.read_file(open(args.channels_file), args.channels_file)
     for section in config.sections():
-        channel = make_channel(config[section])
+
+        channel = Channel(**dict(config[section].items()))
+        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]['name'] = channel.release_name
+            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]['name'] = git_revision_name(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)
 
 
+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 '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.append(
+            'f: f { name = "%s"; channelName = "%s"; src = builtins.storePath "%s"; }' %
+            (config[section]['release_name'], section, tarball))
+    v.status('Installing channels with nix-env')
+    process = subprocess.run(
+        [
+            'nix-env',
+            '--profile',
+            '/nix/var/nix/profiles/per-user/%s/channels' %
+            getpass.getuser(),
+            '--show-trace',
+            '--file',
+            '<nix/unpack-channel.nix>',
+            '--install',
+            '--from-expression'] +
+        exprs)
+    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.set_defaults(func=pin)
+    parser_update = subparsers.add_parser('update')
+    parser_update.add_argument('channels_file', type=str)
+    parser_update.set_defaults(func=update)
     args = parser.parse_args()
     args.func(args)
 
-- 
2.44.1