Merge ~mwhudson/curtin:simplify-apt_update into curtin:master

[Michael Hudson-Doyle]

distro: remove disabling of deb-src lines in apt_update

The current code has the side-effect of ignoring deb822 .sources files
which is a problem that could be fixed but really it's hard to see why
this code is still useful (we do not expect to deploy images with
deb-src enabled!) so just deleting it makes more sense.

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:242ad6fe77f851698fda78e87bd349c01226ae48
https://jenkins.canonical.com/server-team/job/curtin-ci/188/
Executed test runs:
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/188/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/188/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/188/
    FAILURE: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/188/

Click here to trigger a rebuild:
https://jenkins.canonical.com/server-team/job/curtin-ci/188//rebuild

review: Needs Fixing (continuous-integration)

[Dan Bungert (dbungert)]

review: Approve

b3b8177... by Michael Hudson-Doyle on 2023-08-30

flakes

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:b3b81771a2b368c564bb7bd3735b159d1fdddae9
https://jenkins.canonical.com/server-team/job/curtin-ci/190/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-amd64/190/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-arm64/190/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-ppc64el/190/
    SUCCESS: https://jenkins.canonical.com/server-team/job/curtin-ci/nodes=metal-s390x/190/

Click here to trigger a rebuild:
https://jenkins.canonical.com/server-team/job/curtin-ci/190//rebuild

review: Approve (continuous-integration)

diff --git a/curtin/distro.py b/curtin/distro.py
index 433004c..622a520 100644
--- a/curtin/distro.py
+++ b/curtin/distro.py
@@ -3,8 +3,6 @@ import glob
 from collections import namedtuple
 import os
 import re
-import shutil
-import tempfile
 import textwrap
 from typing import Optional, Sequence
 
@@ -229,14 +227,7 @@ def apt_update(target=None, env=None, force=False, comment=None,
 
     restore_perms = []
 
-    abs_tmpdir = tempfile.mkdtemp(dir=target_path(target, "/tmp"))
     try:
-        abs_slist = abs_tmpdir + "/sources.list"
-        abs_slistd = abs_tmpdir + "/sources.list.d"
-        ch_tmpdir = "/tmp/" + os.path.basename(abs_tmpdir)
-        ch_slist = ch_tmpdir + "/sources.list"
-        ch_slistd = ch_tmpdir + "/sources.list.d"
-
         # this file gets executed on apt-get update sometimes. (LP: #1527710)
         motd_update = target_path(
             target, "/usr/lib/update-notifier/update-motd-updates-available")
@@ -244,23 +235,9 @@ def apt_update(target=None, env=None, force=False, comment=None,
         if pmode is not None:
             restore_perms.append((motd_update, pmode),)
 
-        # create tmpdir/sources.list with all lines other than deb-src
-        # avoid apt complaining by using existing and empty dir for sourceparts
-        os.mkdir(abs_slistd)
-        with open(abs_slist, "w") as sfp:
-            for sfile in listfiles:
-                with open(sfile, "r") as fp:
-                    contents = fp.read()
-                for line in contents.splitlines():
-                    line = line.lstrip()
-                    if not line.startswith("deb-src"):
-                        sfp.write(line + "\n")
-
         update_cmd = [
             'apt-get', '--quiet',
             '--option=Acquire::Languages=none',
-            '--option=Dir::Etc::sourcelist=%s' % ch_slist,
-            '--option=Dir::Etc::sourceparts=%s' % ch_slistd,
             'update']
 
         # do not using 'run_apt_command' so we can use 'retries' to subp
@@ -269,8 +246,6 @@ def apt_update(target=None, env=None, force=False, comment=None,
     finally:
         for fname, perms in restore_perms:
             os.chmod(fname, perms)
-        if abs_tmpdir:
-            shutil.rmtree(abs_tmpdir)
 
     with open(marker, "w") as fp:
         fp.write(comment + "\n")