issue #1: synchronise programs' schedules and later diffusions (update, delete); fix signal import in apps

aircox/__init__.py

@@ -0,0 +1,3 @@
+
+default_app_config = 'aircox.apps.AircoxConfig'
+

aircox/admin.py

@@ -81,9 +81,8 @@ class ProgramAdmin(NameableAdmin):
     schedule.boolean = True
     schedule.short_description = _("Schedule")
 
-    list_display = ('id', 'name', 'active', 'schedule')
-    fields = NameableAdmin.fields + [ 'active', 'station' ]
-    # TODO list_display
+    list_display = ('id', 'name', 'active', 'schedule', 'sync')
+    fields = NameableAdmin.fields + [ 'active', 'station','sync' ]
     inlines = [ ScheduleInline, StreamInline ]
 
     # SO#8074161

aircox/apps.py

@@ -0,0 +1,10 @@
+from django.apps import AppConfig
+
+
+class AircoxConfig(AppConfig):
+    name = 'aircox'
+    verbose_name = 'Aircox'
+
+    def ready(self):
+        import aircox.signals
+

aircox/management/commands/diffusions_monitor.py

@@ -128,16 +128,18 @@ class Command (BaseCommand):
             '--update', action='store_true',
             help='generate (unconfirmed) diffusions for the given month. '
                  'These diffusions must be confirmed manually by changing '
-                 'their type to "normal"')
+                 'their type to "normal"'
+        )
         group.add_argument(
             '--clean', action='store_true',
-            help='remove unconfirmed diffusions older than the given month')
-
+            help='remove unconfirmed diffusions older than the given month'
+        )
         group.add_argument(
             '--check', action='store_true',
-            help='check future unconfirmed diffusions from the given date '
-                 'agains\'t schedules and remove it if that do not match any '
-                 'schedule')
+            help='check unconfirmed later diffusions from the given '
+                 'date again'\'t schedule. If no schedule is found, remove '
+                 'it.'
+        )
 
         group = parser.add_argument_group('date')
         group.add_argument(
@@ -161,7 +163,6 @@ class Command (BaseCommand):
                  'diffusions except those that conflicts with others'
         )
 
-
     def handle (self, *args, **options):
         date = tz.datetime(year = options.get('year'),
                                  month = options.get('month'),

aircox/models.py

@@ -294,6 +294,11 @@ class Program(Nameable):
         default = True,
         help_text = _('if not checked this program is no longer active')
     )
+    sync = models.BooleanField(
+        _('syncronise'),
+        default = True,
+        help_text = _('update later diffusions according to schedule changes')
+    )
 
     @property
     def path(self):
@@ -503,6 +508,24 @@ class Schedule(models.Model):
         help_text = 'this schedule is a rerun of this one',
     )
 
+    # initial cached data
+    __initial = None
+
+    def changed(self, fields = ['date','duration','frequency']):
+        initial = self._Schedule__initial
+        if not initial:
+            return
+
+        before, now = self.__initial, self.__dict__
+        before, now = {
+            f: getattr(before, f) for f in fields
+            if hasattr(before, f)
+        }, {
+            f: getattr(now, f) for f in fields
+            if hasattr(now, f)
+        }
+        return before == now
+
     @property
     def end(self):
         return self.date + utils.to_timedelta(self.duration)
@@ -627,6 +650,10 @@ class Schedule(models.Model):
         ]
         return diffusions
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.__initial = self.__dict__.copy()
+
     def __str__(self):
         return ' | '.join([ '#' + str(self.id), self.program.name,
                             self.get_frequency_display(),

aircox/signals.py

@@ -0,0 +1,63 @@
+from django.db.models.signals import post_save, pre_delete
+
+from django.dispatch import receiver
+from django.utils.translation import ugettext as _, ugettext_lazy
+from django.contrib.contenttypes.models import ContentType
+
+import aircox.models as models
+import aircox.utils as utils
+
+# FIXME: avoid copy of the code in schedule_post_saved and
+#        schedule_pre_delete
+
+@receiver(post_save, sender=models.Schedule)
+def schedule_post_saved(sender, instance, created, *args, **kwargs):
+    if not instance.program.sync:
+        return
+
+    initial = instance._Schedule__initial
+    if not initial or not instance.changed(['date','duration', 'frequency']):
+        return
+
+    # old schedule and timedelta
+    old_sched = models.Schedule(
+        date = initial['date'],
+        duration = initial['duration'],
+        frequency = initial['frequency'],
+    )
+    delta = instance.date - old_sched.date
+
+    # update diffusions...
+    qs = models.Diffusion.objects.get_after().filter(
+        program = instance.program
+    )
+    for diff in qs:
+        if not old_sched.match(diff.date):
+            continue
+        diff.start += delta
+        diff.end = diff.start + utils.to_timedelta(instance.duration)
+        diff.save()
+
+@receiver(pre_delete, sender=models.Schedule)
+def schedule_pre_delete(sender, instance, *args, **kwargs):
+    if not instance.program.sync:
+        return
+
+    initial = instance._Schedule__initial
+    if not initial or not instance.changed(['date','duration', 'frequency']):
+        return
+
+    old_sched = models.Schedule(
+        date = initial['date'],
+        duration = initial['duration'],
+        frequency = initial['frequency'],
+    )
+
+    qs = models.Diffusion.objects.get_after().filter(
+        program = instance.program
+    )
+    for diff in qs:
+        if not old_sched.match(diff.date):
+            continue
+        diff.delete()
+