setup: Run first time setup with apt

Due to problems with running PackageKit inside foriegn binary Qemu, this
is a fallback solution to use apt-get directly instead.

plinth/package.py

@@ -21,6 +21,7 @@ Framework for installing and updating distribution packages
 
 from django.utils.translation import ugettext as _
 import logging
+import subprocess
 
 from plinth.utils import import_from_gi
 glib = import_from_gi('GLib', '2.0')
@@ -166,3 +167,25 @@ class Transaction(object):
         else:
             logger.info('Unhandle packagekit progress callback - %s, %s',
                         progress, progress_type)
+
+
+class AptTransaction(object):
+    """Install a package using Apt."""
+    def __init__(self, package_names):
+        """Initialize transaction object."""
+        self.package_names = package_names
+
+    def install(self):
+        """Run a PackageKit transaction to install given packages.
+
+        Plinth needs to be running as root when calling this.
+        Currently, this is meant to be only during first time setup
+        when --setup is argument is passed.
+        """
+        try:
+            subprocess.run(['apt-get', 'update'])
+            subprocess.run(['apt-get', '-y', 'install'] + self.package_names,
+                           check=True)
+        except subprocess.CalledProcessError as exception:
+            logger.exception('Error installing package: %s', exception)
+            raise

plinth/setup.py

@@ -27,6 +27,8 @@ import plinth
 
 logger = logging.getLogger(__name__)
 
+running_initial_setup = False
+
 
 class Helper(object):
     """Helper routines for modules to show progress."""
@@ -91,6 +93,11 @@ class Helper(object):
         """Install a set of packages marking progress."""
         logger.info('Running install for module - %s, packages - %s',
                     self.module_name, package_names)
+        if running_initial_setup:
+            transaction = package.AptTransaction(package_names)
+            transaction.install()
+            return
+
         transaction = package.Transaction(package_names)
         self.current_operation = {
             'step': 'install',
@@ -153,6 +160,8 @@ def init(module_name, module):
 def setup_all_modules(essential=False):
     """Run setup on all essential modules and exit."""
     logger.info('Running setup for all modules, essential - %s', essential)
+    global running_initial_setup
+    running_initial_setup = True
     for module_name, module in plinth.module_loader.loaded_modules.items():
         if essential and not getattr(module, 'is_essential', False):
             continue