Call curtin installer from subiquity

Hacky method, but in welcome controller, use subprocess to
call a script which invokes curtin at a known location with
a specific set of parameters.

Modify the installer configuration and start-up scripts to
ensure Subiquity runs on tty1 and keeps the service running.

Upon hitting 'Confirm' Subiquity will exec curtin_wrap.sh
which calls the *real* curtin.  Cloud-init user-data has been
modified to unpack the curtin archive embedded.

When complete, the target.img file is bootable.

Signed-off-by: Ryan Harper <ryan.harper@canonical.com>

bin/curtin_wrap.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+CMD="-v --showtrace install cp:///"
+CURTIN="/usr/local/curtin/bin/curtin"
+OUTPUT="/tmp/.curtin_wrap_ran"
+
+if [ -e $CURTIN ]; then 
+   $CURTIN $CMD | tee -a $OUTPUT
+else
+   echo "$CURTIN not found" > $OUTPUT
+   echo $CURTIN $CMD | tee -a $OUTPUT
+fi
+echo "Shutting down after running $CURTIN $CMD"
+telinit 0

installer/geninstaller

@@ -302,7 +302,7 @@ generate_seed() {
     # append the curtin-cmd file
     rm -f ${seed}/user-data &&
     cp $installer_user_data $seed/user-data &&
-    userdata_write_file "/usr/local/bin/curtin" \
+    userdata_write_file "/usr/local/bin/curtin-archive" \
                          "root:root" "0755" "none" \
                          "$curtin_cmd" >> $seed/user-data || {
         log "Failed to embed curtin into $seed";

installer/resources/user-data/installer-user-data

@@ -6,24 +6,20 @@ output: {all: '| tee -a /var/log/cloud-init-output.log'}
 packages:
  - python-urwid
  - python3-urwid
-power_state:
- mode: poweroff
- message: Bye Bye
- timeout: 30
 runcmd:
     - cp /usr/share/doc/python-urwid/examples/input_test.py /tmp/installer.py
     - tar -C /usr/local -xf /tmp/subiquity.tar
     - chmod +x /tmp/installer.py /usr/local/bin/subiquity
+    - (cd /usr/local && bin/curtin-archive extract --no-execute)
     - systemctl enable subiquity.service
     - systemctl stop getty@tty1.service
 #   - systemctl stop serial-getty@ttyS0.service
     - /tmp/installer.sh
-    - telinit 0
 write_files:
 -   content: |
         #!/bin/bash
 
-        chvt 2
+        chvt 1
         systemctl start subiquity
         # restart getty service after exiting "installer"
         # systemctl stop serial-getty@ttyS0.service
@@ -51,4 +47,4 @@ write_files:
         WantedBy=default.target
     path: /lib/systemd/system/subiquity.service
     owner: root:root
-    permissions: '0755'
+    permissions: '0644'

subiquity/controllers/welcome.py

@@ -15,6 +15,7 @@
 
 from subiquity.controllers import BaseController
 from subiquity.views.welcome import WelcomeView
+import subprocess
 
 
 class WelcomeController(BaseController):
@@ -25,4 +26,5 @@ class WelcomeController(BaseController):
         return WelcomeView(self.finish)
 
     def finish(self, code, val):
+        subprocess.check_call("/usr/local/bin/curtin_wrap.sh")
         raise SystemExit("Saw res: {}, val: {}".format(code, val))