xmpp: Preseed debconf values before ejabberd and jwchat packages are installed.

actions/xmpp

@@ -39,6 +39,14 @@ def parse_arguments():
     parser = argparse.ArgumentParser()
     subparsers = parser.add_subparsers(dest='subcommand', help='Sub command')
 
+    # Preseed debconf values before packages are installed.
+    pre_install = subparsers.add_parser(
+        'pre-install',
+        help='Preseed debconf values before packages are installed.')
+    pre_install.add_argument(
+        '--domainname',
+        help='The domain name that will be used by the XMPP service.')
+
     # Prepare ejabberd for hostname change
     pre_hostname_change = subparsers.add_parser(
         'pre-change-hostname',
@@ -80,6 +88,21 @@ def parse_arguments():
     return parser.parse_args()
 
 
+def subcommand_pre_install(arguments):
+    """Preseed debconf values before packages are installed."""
+    domainname = arguments.domainname.strip("'")
+    if not domainname:
+        # If new domainname is blank, use hostname instead.
+        domainname = socket.gethostname()
+
+    subprocess.check_output(
+        ['debconf-set-selections'],
+        input=b'ejabberd ejabberd/hostname string ' + domainname.encode())
+    subprocess.check_output(
+        ['debconf-set-selections'],
+        input=b'jwchat jwchat/ApacheServerName string ' + domainname.encode())
+
+
 def subcommand_pre_change_hostname(arguments):
     """Prepare ejabberd for hostname change"""
     old_hostname = arguments.old_hostname

plinth/modules/xmpp/xmpp.py

@@ -61,8 +61,17 @@ def init():
     domainname_change.connect(on_domainname_change)
 
 
+def before_install():
+    """Preseed debconf values before the packages are installed."""
+    fqdn = socket.getfqdn()
+    domainname = '.'.join(fqdn.split('.')[1:])
+    LOGGER.info('XMPP service domainname will be ', domainname)
+    actions.superuser_run('xmpp', ['pre-install', '--domainname', domainname])
+
+
 @login_required
-@package.required(['jwchat', 'ejabberd'])
+@package.required(['jwchat', 'ejabberd'],
+                  before_install=before_install)
 def index(request):
     """Serve XMPP page"""
     return TemplateResponse(request, 'xmpp.html',

plinth/package.py

@@ -49,13 +49,14 @@ class PackageException(Exception):
 class Transaction(object):
     """Information about an ongoing transaction."""
 
-    def __init__(self, package_names, on_install=None):
+    def __init__(self, package_names, before_install=None, on_install=None):
         """Initialize transaction object.
 
         Set most values to None until they are sent as progress update.
         """
         self.package_names = package_names
         # XXX: This is hack, remove after implementing proper setup mechanism.
+        self.before_install = before_install
         self.on_install = on_install
 
         # Progress
@@ -97,6 +98,15 @@ class Transaction(object):
 
     def _install(self):
         """Run a PackageKit transaction to install given packages."""
+        try:
+            if self.before_install:
+                self.before_install()
+        except Exception as exception:
+            logger.exception('Error during setup before install - %s',
+                             exception)
+            self.finish(exception)
+            return
+
         try:
             self._do_install()
         except PackageException as exception:
@@ -209,7 +219,7 @@ class Transaction(object):
         return self.exception
 
 
-def required(package_names, on_install=None):
+def required(package_names, before_install=None, on_install=None):
     """Decorate a view to check and install required packages."""
 
     def wrapper2(func):
@@ -223,7 +233,8 @@ def required(package_names, on_install=None):
 
             view = plinth.views.PackageInstallView.as_view()
             return view(request, package_names=package_names,
-                        on_install=on_install, *args, **kwargs)
+                        before_install=before_install, on_install=on_install,
+                        *args, **kwargs)
 
         return wrapper
 
@@ -290,12 +301,14 @@ def is_installing(package_names):
     return frozenset(package_names) in transactions
 
 
-def start_install(package_names, on_install=None):
+def start_install(package_names, before_install=None, on_install=None):
     """Start a PackageKit transaction to install given list of packages.
 
     This operation is non-blocking at it spawns a new thread.
     """
-    transaction = Transaction(package_names, on_install=on_install)
+    transaction = Transaction(package_names,
+                              before_install=before_install,
+                              on_install=on_install)
     transactions[frozenset(package_names)] = transaction
 
     transaction.start_install()