Backups: uploading and import with temporarily stored file

Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/__main__.py

@@ -308,6 +308,7 @@ def configure_django():
             'plinth.middleware.FirstSetupMiddleware',
             'plinth.modules.first_boot.middleware.FirstBootMiddleware',
             'plinth.middleware.SetupMiddleware',
+            'plinth.modules.backups.middleware.BackupsMiddleware',
         ),
         ROOT_URLCONF='plinth.urls',
         SECURE_BROWSER_XSS_FILTER=True,

plinth/modules/backups/__init__.py

@@ -49,6 +49,8 @@ MANIFESTS_FOLDER = '/var/lib/plinth/backups-manifests/'
 BACKUP_FOLDER_NAME = 'FreedomBox-backups'
 # default backup path for temporary actions like imports or download
 TMP_BACKUP_PATH = '/tmp/freedombox-backup.tar.gz'
+# session variable name that stores when a backup file should be deleted
+SESSION_BACKUP_VARIABLE = 'fbx-backup-filestamp'
 
 
 def init():
@@ -109,6 +111,10 @@ def create_archive(name, app_names):
 def delete_archive(name):
     actions.superuser_run('backups', ['delete', '--name', name])
 
+def delete_tmp_backup_file():
+    if os.path.isfile(TMP_BACKUP_PATH):
+        os.remove(TMP_BACKUP_PATH)
+
 
 def export_archive(name, location, tmp_dir=False):
     # TODO: find a better solution for distinguishing exports to /tmp
@@ -194,6 +200,12 @@ def _restore_handler(packet):
                           input=locations_data.encode())
 
 
+def restore_from_tmp(apps=None):
+    """Restore files from temporary backup file"""
+    api.restore_apps(_restore_handler, app_names=apps, create_subvolume=False,
+                 backup_file=TMP_BACKUP_PATH)
+
+
 def restore_exported(device, archive_name, apps=None):
     """Restore files from exported backup archive."""
     filename = find_exported_archive(device, archive_name)

plinth/modules/backups/forms.py

@@ -75,6 +75,20 @@ class ExportArchiveForm(forms.Form):
                                        for location in get_export_locations()]
 
 
+class RestoreFromTmpForm(forms.Form):
+    selected_apps = forms.MultipleChoiceField(
+        label=_('Restore apps'),
+        widget=forms.CheckboxSelectMultiple)
+
+    def __init__(self, *args, **kwargs):
+        """Initialize the form with selectable apps."""
+        apps = kwargs.pop('apps')
+        super().__init__(*args, **kwargs)
+        self.fields['selected_apps'].choices = [
+            (app[0], app[1].name) for app in apps]
+        self.fields['selected_apps'].initial = [app[0] for app in apps]
+
+
 class RestoreForm(forms.Form):
     selected_apps = forms.MultipleChoiceField(
         label=_('Restore apps'),
@@ -123,3 +137,10 @@ class UploadForm(forms.Form):
                     "File %s already exists" % file.name)
             else:
                 self.cleaned_data.update({'filepath': filepath})
+
+
+class UploadToTmpForm(forms.Form):
+    file = forms.FileField(label=_('Upload File'), required=True,
+            validators=[FileExtensionValidator(['gz'],
+                'Backup files have to be in .tar.gz format')],
+            help_text=_('Select the backup file you want to upload'))

plinth/modules/backups/middleware.py

@@ -0,0 +1,48 @@
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+"""
+Django middleware to redirect to firstboot wizard if it has not be run
+yet.
+"""
+
+import logging
+import random
+import time
+
+from django.utils.deprecation import MiddlewareMixin
+
+from plinth.modules import backups
+
+LOGGER = logging.getLogger(__name__)
+
+
+class BackupsMiddleware(MiddlewareMixin):
+    """Delete outdated backup file."""
+
+    @staticmethod
+    def process_request(request):
+        """Handle a request as Django middleware request handler."""
+        if random.random() > 0.9:
+            if request.session.has_key(backups.SESSION_BACKUP_VARIABLE):
+                now = time.time()
+                if now > request.session[backups.SESSION_BACKUP_VARIABLE]:
+                    backups.delete_tmp_backup_file()
+                    del request.session[backups.SESSION_BACKUP_VARIABLE]
+            else:
+                backups.delete_tmp_backup_file()
+        return

plinth/modules/backups/templates/backups_restore_from_tmp.html

@@ -0,0 +1,45 @@
+{% extends "base.html" %}
+{% comment %}
+#
+# This file is part of FreedomBox.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+{% endcomment %}
+
+{% load bootstrap %}
+{% load i18n %}
+
+{% block content %}
+  <h2>{{ title }}</h2>
+
+  <p>
+    <form class="form" method="post">
+      {% csrf_token %}
+
+      {{ form|bootstrap }}
+
+      <input type="submit" class="btn btn-primary"
+             value="{% blocktrans trimmed %}
+                      Restore data
+                    {% endblocktrans %}"/>
+      <a title="{% trans 'Abort' %}"
+         role="button" class="btn btn-warning"
+         href="{% url 'backups:index' %}">
+        {% trans 'Abort' %}
+      </a>
+    </form>
+  </p>
+
+{% endblock %}

plinth/modules/backups/urls.py

@@ -22,7 +22,7 @@ from django.conf.urls import url
 
 from .views import IndexView, CreateArchiveView, DownloadArchiveView, \
     DeleteArchiveView, ExportArchiveView, RestoreView, UploadArchiveView, \
-    ExportAndDownloadView
+    ExportAndDownloadView, RestoreFromTmpView
 
 urlpatterns = [
     url(r'^sys/backups/$', IndexView.as_view(), name='index'),
@@ -38,4 +38,6 @@ urlpatterns = [
     url(r'^sys/backups/upload/$', UploadArchiveView.as_view(), name='upload'),
     url(r'^sys/backups/restore/(?P<device>[^/]+)/(?P<name>[^/]+)/$',
         RestoreView.as_view(), name='restore'),
+    url(r'^sys/backups/restore-from-tmp/$',
+        RestoreFromTmpView.as_view(), name='restore-from-tmp'),
 ]

plinth/modules/backups/views.py

@@ -19,8 +19,9 @@ Views for the backups app.
 """
 
 import mimetypes
-import os
 from datetime import datetime
+import os
+import time
 from urllib.parse import unquote
 
 from django.contrib import messages
@@ -34,8 +35,11 @@ from django.views.generic import View, FormView, TemplateView
 
 from plinth.modules import backups
 
-from . import api, find_exported_archive, TMP_BACKUP_PATH, forms
+from . import api, find_exported_archive, TMP_BACKUP_PATH, forms, \
+        SESSION_BACKUP_VARIABLE, delete_tmp_backup_file
 
+# number of seconds an uploaded backup file should be kept/stored
+KEEP_UPLOADED_BACKUP_FOR = 60*10
 
 subsubmenu = [{
     'url': reverse_lazy('backups:index'),
@@ -161,16 +165,14 @@ class create_temporary_backup_file:
         return self.path
 
     def __exit__(self, type, value, traceback):
-        if os.path.isfile(self.path):
-            os.remove(self.path)
+        delete_tmp_backup_file()
 
 
 class UploadArchiveView(SuccessMessageMixin, FormView):
-    form_class = forms.UploadForm
+    form_class = forms.UploadToTmpForm
     prefix = 'backups'
     template_name = 'backups_upload.html'
-    success_url = reverse_lazy('backups:index')
-    success_message = _('Backup file uploaded.')
+    success_url = reverse_lazy('backups:restore-from-tmp')
 
     def get_context_data(self, **kwargs):
         """Return additional context for rendering the template."""
@@ -181,9 +183,11 @@ class UploadArchiveView(SuccessMessageMixin, FormView):
 
     def form_valid(self, form):
         """store uploaded file."""
-        with open(form.cleaned_data['filepath'], 'wb+') as destination:
+        with open(TMP_BACKUP_PATH, 'wb+') as destination:
             for chunk in self.request.FILES['backups-file'].chunks():
                 destination.write(chunk)
+        self.request.session[SESSION_BACKUP_VARIABLE] = time.time() + \
+                KEEP_UPLOADED_BACKUP_FOR
         return super().form_valid(form)
 
 
@@ -223,7 +227,10 @@ class RestoreView(SuccessMessageMixin, FormView):
         """Save some data used to instantiate the form."""
         device = unquote(self.kwargs['device'])
         name = unquote(self.kwargs['name'])
-        filename = backups.find_exported_archive(device, name)
+        if self.kwargs['use_tmp_file'] == 'true':
+            filename = TMP_BACKUP_PATH
+        else:
+            filename = backups.find_exported_archive(device, name)
         return backups.get_export_apps(filename)
 
     def get_form_kwargs(self):
@@ -250,3 +257,47 @@ class RestoreView(SuccessMessageMixin, FormView):
             unquote(self.kwargs['device']), self.kwargs['name'],
             form.cleaned_data['selected_apps'])
         return super().form_valid(form)
+
+
+class RestoreFromTmpView(SuccessMessageMixin, FormView):
+    """View to restore files from an exported archive.
+    
+    TODO: combine with RestoreView"""
+    # TODO: display more information about the backup, like the date
+    form_class = forms.RestoreFromTmpForm
+    prefix = 'backups'
+    template_name = 'backups_restore_from_tmp.html'
+    success_url = reverse_lazy('backups:index')
+    success_message = _('Restored files from backup.')
+
+    def get(self, *args, **kwargs):
+        if not os.path.isfile(TMP_BACKUP_PATH):
+            messages.error(self.request, _('No backup file found.'))
+            return redirect(reverse_lazy('backups:index'))
+        else:
+            return super().get(*args, **kwargs)
+
+    def _get_included_apps(self):
+        """Save some data used to instantiate the form."""
+        return backups.get_export_apps(TMP_BACKUP_PATH)
+
+    def get_form_kwargs(self):
+        """Pass additional keyword args for instantiating the form."""
+        kwargs = super().get_form_kwargs()
+        included_apps = self._get_included_apps()
+        installed_apps = api.get_all_apps_for_backup()
+        kwargs['apps'] = [
+            app for app in installed_apps if app[0] in included_apps
+        ]
+        return kwargs
+
+    def get_context_data(self, **kwargs):
+        """Return additional context for rendering the template."""
+        context = super().get_context_data(**kwargs)
+        context['title'] = _('Restore data')
+        return context
+
+    def form_valid(self, form):
+        """Restore files from the archive on valid form submission."""
+        backups.restore_from_tmp(form.cleaned_data['selected_apps'])
+        return super().form_valid(form)