fix(management): handle errors in object loading and application deployments instead of throwing exceptions

This will handle the DeisExceptions and derived Exceptions

Fixes #761
Fixes #741

Author: helgi

rootfs/api/management/commands/load_db_state_to_k8s.py

@@ -2,6 +2,7 @@
 from django.shortcuts import get_object_or_404
 
 from api.models import Key, App, Domain, Certificate, Config
+from api.exceptions import DeisException
 
 
 class Command(BaseCommand):
@@ -13,7 +14,11 @@ def handle(self, *args, **options):
         print("Publishing DB state to kubernetes...")
         for model in (Key, App, Domain, Certificate, Config):
             for obj in model.objects.all():
-                obj.save()
+                try:
+                    obj.save()
+                except DeisException as error:
+                    print('ERROR: Problem saving to model {} for {}'
+                          'due to {}'.format(str(model.__name__), str(obj), str(error)))
 
         # certificates have to be attached to domains to create k8s secrets
         for cert in Certificate.objects.all():
@@ -29,6 +34,11 @@ def handle(self, *args, **options):
                 print('WARNING: {} has no build associated with '
                       'its latest release. Skipping deployment...'.format(application))
                 continue
-            application.deploy(rel)
+
+            try:
+                application.deploy(rel)
+            except DeisException as error:
+                print('ERROR: There was a problem deploying {} '
+                      'due to {}'.format(application, str(error)))
 
         print("Done Publishing DB state to kubernetes.")

rootfs/api/models/config.py

@@ -102,7 +102,8 @@ def set_tags(self, previous_config):
         if old_tags:
             old = ['{}={}'.format(key, value) for key, value in old_tags.items()]
             new = set(labels) - set(old)
-            message += ' - Addition of {} is the cause'.format(', '.join(new))
+            if new:
+                message += ' - Addition of {} is the cause'.format(', '.join(new))
 
         raise DeisException(message)