implement the bulk of subiquity-configure-apt in the server process

This uses a kind of crazy approach where the hook script we get curtin
to run makes an API call to the server process to do the actual
configuration. I can't work out if this is genius or insane or both but
anyway it is only a step on to the way to doing the apt configuration
before we start curtin so it won't be around for long.

bin/subiquity-configure-apt

@@ -1,67 +1,3 @@
 #!/bin/bash -eux
 
-# Configure apt so that installs from the pool on the cdrom are preferred
+curl --fail --unix-socket /run/subiquity/socket --data '' a/install/configure_apt
-# during installation but not in the installed system.
-#
-# This has a few steps.
-#
-# 1. As the remaining steps mean that any changes to apt configuration are do
-#    not persist into the installed system, we get curtin to configure apt a
-#    bit earlier than it would by default.
-#
-# 2. Bind-mount the cdrom into the installed system as /run/cdrom
-#
-# 3. Set up an overlay over /target/etc/apt. This means that any changes we
-#    make will not persist into the installed system and we do not have to
-#    worry about cleaning up after ourselves.
-#
-# 4. Configure apt in /target to look at the pool on the cdrom.  This has two
-#    subcases:
-#
-#     a. if we expect the network to be working, this basically means
-#        prepending "deb file:///run/cdrom $(lsb_release -sc) main restricted"
-#        to the sources.list file.
-#
-#     b. if the network is not expected to be working, we replace the
-#        sources.list with a file just referencing the cdrom.
-#
-# 5. If the network is not expected to be working, we also set up an overlay
-#    over /target/var/lib/apt/lists (if the network is working, we'll run "apt
-#    update" after the /target/etc/apt overlay has been cleared).
-
-if [ -z "$TARGET_MOUNT_POINT" ]; then
-    # Nothing good can happen from running this script without
-    # TARGET_MOUNT_POINT set.
-    exit 1;
-fi
-
-PY=$1
-HAS_NETWORK=$2
-
-$PY -m curtin apt-config
-
-setup_overlay () {
-    local dir=$1
-    local t=$(mktemp -d)
-    mkdir $t/work $t/upper
-    mount -t overlay overlay -o lowerdir=$dir,workdir=$t/work,upperdir=$t/upper $dir
-}
-
-setup_overlay $TARGET_MOUNT_POINT/etc/apt
-
-mkdir -p "$TARGET_MOUNT_POINT/cdrom"
-mount --bind /cdrom "$TARGET_MOUNT_POINT/cdrom"
-
-if [ $HAS_NETWORK = 'true' ]; then
-    mv "$TARGET_MOUNT_POINT/etc/apt/sources.list" "$TARGET_MOUNT_POINT/etc/apt/sources.list.d/original.list"
-else
-    # Do not use the configured proxy during the install if one was configured.
-    rm -f $TARGET_MOUNT_POINT/etc/apt/apt.conf.d/90curtin-aptproxy
-    setup_overlay $TARGET_MOUNT_POINT/var/lib/apt/lists
-fi
-
-cat > "$TARGET_MOUNT_POINT/etc/apt/sources.list" <<EOF
-deb [check-date=no] file:///cdrom $(chroot $TARGET_MOUNT_POINT lsb_release -sc) main restricted
-EOF
-
-$PY -m curtin in-target -- apt-get update

subiquity/common/apidef.py

@@ -294,6 +294,11 @@ class API:
         def GET() -> TimeZoneInfo: ...
         def POST(tz: str): ...
 
+    class install:
+        class configure_apt:
+            def POST():
+                "Not for client use."
+
     class shutdown:
         def POST(mode: ShutdownMode, immediate: bool = False): ...
 

subiquity/models/subiquity.py

@@ -18,7 +18,6 @@ from collections import OrderedDict
 import functools
 import logging
 import os
-import sys
 import uuid
 import yaml
 
@@ -338,7 +337,6 @@ class SubiquityModel:
             'curthooks_commands': {
                 '001-configure-apt': [
                     resource_path('bin/subiquity-configure-apt'),
-                    sys.executable, str(self.network.has_network).lower(),
                     ],
                 },
 

subiquity/server/controllers/install.py

@@ -18,6 +18,7 @@ import logging
 import os
 import re
 import shutil
+import tempfile
 
 from curtin.commands.install import (
     ERROR_TARFILE,
@@ -31,7 +32,9 @@ from subiquitycore.async_helpers import (
     run_in_thread,
     )
 from subiquitycore.context import with_context
+from subiquitycore.lsb_release import lsb_release
 
+from subiquity.common.apidef import API
 from subiquity.common.errorreport import ErrorReportKind
 from subiquity.common.types import (
     ApplicationState,
@@ -47,7 +50,6 @@ from subiquity.server.controller import (
     SubiquityController,
     )
 
-
 log = logging.getLogger("subiquity.server.controllers.install")
 
 
@@ -72,6 +74,8 @@ class TracebackExtractor:
 
 class InstallController(SubiquityController):
 
+    endpoint = API.install
+
     def __init__(self, app):
         super().__init__(app)
         self.model = app.base_model
@@ -80,6 +84,9 @@ class InstallController(SubiquityController):
         self.unattended_upgrades_ctx = None
         self.tb_extractor = TracebackExtractor()
 
+    def interactive(self):
+        return True
+
     def stop_uu(self):
         if self.app.state == ApplicationState.UU_RUNNING:
             self.app.update_state(ApplicationState.UU_CANCELLING)
@@ -147,14 +154,14 @@ class InstallController(SubiquityController):
 
             self.app.update_state(ApplicationState.RUNNING)
 
-            config_location = self.write_config()
+            self.config_location = self.write_config()
 
             if os.path.exists(self.model.target):
                 await self.unmount_target(
                     context=context, target=self.model.target)
 
             await self.curtin_install(
-                context=context, config_location=config_location)
+                context=context, config_location=self.config_location)
 
             self.app.update_state(ApplicationState.POST_WAIT)
 
@@ -257,6 +264,88 @@ class InstallController(SubiquityController):
                self.unattended_upgrades_cmd is not None:
                 self.unattended_upgrades_cmd.proc.terminate()
 
+    async def configure_apt_POST(self, context):
+        # Configure apt so that installs from the pool on the cdrom are
+        # preferred during installation but not in the installed system.
+        #
+        # This has a few steps.
+        #
+        # 1. As the remaining steps mean that any changes to apt configuration
+        #    are do not persist into the installed system, we get curtin to
+        #    configure apt a bit earlier than it would by default.
+        #
+        # 2. Bind-mount the cdrom into the installed system as /cdrom.
+        #
+        # 3. Set up an overlay over /target/etc/apt. This means that any
+        #    changes we make will not persist into the installed system and we
+        #    do not have to worry about cleaning up after ourselves.
+        #
+        # 4. Configure apt in /target to look at the pool on the cdrom.  This
+        #    has two subcases:
+        #
+        #     a. if we expect the network to be working, this basically means
+        #        prepending
+        #        "deb file:///run/cdrom $(lsb_release -sc) main restricted"
+        #        to the sources.list file.
+        #
+        #     b. if the network is not expected to be working, we replace the
+        #        sources.list with a file just referencing the cdrom.
+        #
+        # 5. If the network is not expected to be working, we also set up an
+        #    overlay over /target/var/lib/apt/lists (if the network is working,
+        #    we'll run "apt update" after the /target/etc/apt overlay has been
+        #    cleared).
+
+        async def mount(device, mountpoint, options=None, type=None):
+            opts = []
+            if options is not None:
+                opts.extend(['-o', options])
+            if type is not None:
+                opts.extend(['-t', type])
+            await self.app.command_runner.run(
+                ['mount'] + opts + [device, mountpoint])
+
+        async def unmount(mountpoint):
+            await self.app.command_runner.run(['umount', mountpoint])
+
+        async def setup_overlay(dir):
+            tdir = tempfile.mkdtemp()
+            w = f'{tdir}/work'
+            u = f'{tdir}/upper'
+            for d in w, u:
+                os.mkdir(d)
+            await mount(
+                'overlay', dir, type='overlay',
+                options=f'lowerdir={dir},upperdir={u},workdir={w}')
+
+        await run_curtin_command(
+            self.app, context, 'apt-config', '-t', self.tpath(),
+            config=self.config_location)
+
+        await setup_overlay(self.tpath('etc/apt'))
+
+        os.mkdir(self.tpath('cdrom'))
+        await mount('/cdrom', self.tpath('cdrom'), options='bind')
+
+        if self.model.network.has_network:
+            os.rename(
+                self.tpath('etc/apt/sources.list'),
+                self.tpath('etc/apt/sources.list.d/original.list'))
+        else:
+            os.unlink(self.tpath('etc/apt/apt.conf.d/90curtin-aptproxy'))
+            await setup_overlay(self.tpath('var/lib/apt/lists'))
+
+        codename = lsb_release()['codename']
+
+        write_file(
+            self.tpath('etc/apt/sources.list'),
+            f'deb [check-date=no] file:///cdrom {codename} main restricted\n',
+            )
+
+        await run_curtin_command(
+            self.app, context, "in-target", "-t", self.tpath(),
+            "--", "apt-get", "update")
+
 
 uu_apt_conf = b"""\
 # Config for the unattended-upgrades run to avoid failing on battery power or