Improvements on orders

TODO.md

@@ -57,3 +57,8 @@ Remember that, as always with QuerySets, any subsequent chained methods which im
 
 
 * Settings dictionary like DRF2 in order to better override large settings like WEBSITES_APPLICATIONS.etc
+
+
+* DOCUMENT: orchestration.middleware: we need to know when an operation starts and ends in order to perform bulk server updates and also to wait for related objects to be saved (base object is saved first and then related)
+            orders.signales: we perform changes right away because data model state can change under monitoring and other periodik task, and we should keep orders consistency under any situation.
+                             dependency collector with max_recursion that matches the number of dots on service.match and service.metric

orchestra/admin/utils.py

@@ -17,7 +17,7 @@ def get_modeladmin(model, import_module=True):
     """ returns the modeladmin registred for model """
     for k,v in admin.site._registry.iteritems():
         if k is model:
-            return type(v)
+            return v
     if import_module:
         # Sometimes the admin module is not yet imported
         app_label = model._meta.app_label
@@ -32,7 +32,7 @@ def insertattr(model, name, value, weight=0):
     """ Inserts attribute to a modeladmin """
     modeladmin = model
     if models.Model in model.__mro__:
-        modeladmin = get_modeladmin(model)
+        modeladmin = type(get_modeladmin(model))
     # Avoid inlines defined on parent class be shared between subclasses
     # Seems that if we use tuples they are lost in some conditions like changing
     # the tuple in modeladmin.__init__

orchestra/apps/miscellaneous/admin.py

@@ -29,6 +29,13 @@ class MiscServiceAdmin(admin.ModelAdmin):
 class MiscellaneousAdmin(AccountAdminMixin, admin.ModelAdmin):
     list_display = ('service', 'amount', 'account_link')
     
+    def get_fields(self, request, obj=None):
+        if obj is None:
+            return ('service', 'account', 'description', 'amount', 'is_active')
+        if not obj.service.has_amount:
+            return ('service', 'account_link', 'description', 'is_active')
+        return ('service', 'account_link', 'description', 'amount', 'is_active')
+
 
 admin.site.register(MiscService, MiscServiceAdmin)
 admin.site.register(Miscellaneous, MiscellaneousAdmin)

orchestra/apps/miscellaneous/models.py

@@ -7,6 +7,9 @@ from orchestra.core import services
 class MiscService(models.Model):
     name = models.CharField(_("name"), max_length=256)
     description = models.TextField(blank=True)
+    has_amount = models.BooleanField(default=False,
+            help_text=_("Designates whether this service has <tt>amount</tt> "
+                        "property or not."))
     is_active = models.BooleanField(default=True,
             help_text=_("Whether new instances of this service can be created "
                         "or not. Unselect this instead of deleting services."))

orchestra/apps/orders/admin.py

@@ -2,6 +2,7 @@ from django import forms
 from django.contrib import admin
 from django.utils.translation import ugettext_lazy as _
 
+from orchestra.apps.accounts.admin import AccountAdminMixin
 from orchestra.core import services
 
 from .models import Service, Order, MetricStorage
@@ -36,7 +37,7 @@ class ServiceAdmin(admin.ModelAdmin):
         return super(ServiceAdmin, self).formfield_for_dbfield(db_field, **kwargs)
 
 
-class OrderAdmin(admin.ModelAdmin):
+class OrderAdmin(AccountAdminMixin, admin.ModelAdmin):
     pass
 
 

orchestra/apps/orders/helpers.py

@@ -0,0 +1,38 @@
+import inspect
+
+from orchestra.apps.accounts.models import Account
+
+
+def search_for_related(origin, max_depth=2):
+    """
+    Introspects origin object and return the first related service object
+    
+    WARNING this is NOT an exhaustive search but a compromise between cost and
+            flexibility. A more comprehensive approach may be considered if
+            a use-case calls for it.
+    """
+    
+    def related_iterator(node):
+        for field in node._meta.virtual_fields:
+            if hasattr(field, 'ct_field'):
+                yield getattr(node, field.name)
+        for field in node._meta.fields:
+            if field.rel:
+                yield getattr(node, field.name)
+    
+    # BFS model relation transversal
+    queue = [[origin]]
+    while queue:
+        models = queue.pop(0)
+        if len(models) > max_depth:
+            return None
+        node = models[-1]
+        if len(models) > 1:
+            if hasattr(node, 'account') or isinstance(node, Account):
+                return node
+        for related in related_iterator(node):
+            if related not in models:
+                new_models = list(models)
+                new_models.append(related)
+                queue.append(new_models)
+

orchestra/apps/orders/middlewares.py

@@ -1,79 +0,0 @@
-from threading import local
-
-from django.db.models.signals import pre_delete, pre_save
-from django.dispatch import receiver
-from django.http.response import HttpResponseServerError
-
-from orchestra.core import services
-from orchestra.utils.python import OrderedSet
-
-from .models import Order
-
-
-@receiver(pre_save, dispatch_uid='orders.ppre_save_collector')
-def pre_save_collector(sender, *args, **kwargs):
-    if sender in services:
-        OrderMiddleware.collect(Order.SAVE, **kwargs)
-
-@receiver(pre_delete, dispatch_uid='orders.pre_delete_collector')
-def pre_delete_collector(sender, *args, **kwargs):
-    if sender in services:
-        OrderMiddleware.collect(Order.DELETE, **kwargs)
-
-
-class OrderCandidate(object):
-    def __unicode__(self):
-        return "{}.{}()".format(str(self.instance), self.action)
-    
-    def __init__(self, instance, action):
-        self.instance = instance
-        self.action = action
-    
-    def __hash__(self):
-        """ set() """
-        opts = self.instance._meta
-        model = opts.app_label + opts.model_name
-        return hash(model + str(self.instance.pk) + self.action)
-    
-    def __eq__(self, candidate):
-        """ set() """
-        return hash(self) == hash(candidate)
-
-
-class OrderMiddleware(object):
-    """
-    Stores all the operations derived from save and delete signals and executes them
-    at the end of the request/response cycle
-    """
-    # Thread local is used because request object is not available on model signals
-    thread_locals = local()
-    
-    @classmethod
-    def get_order_candidates(cls):
-        # Check if an error poped up before OrdersMiddleware.process_request()
-        if hasattr(cls.thread_locals, 'request'):
-            request = cls.thread_locals.request
-            if not hasattr(request, 'order_candidates'):
-                request.order_candidates = OrderedSet()
-            return request.order_candidates
-        return set()
-    
-    @classmethod
-    def collect(cls, action, **kwargs):
-        """ Collects all pending operations derived from model signals """
-        request = getattr(cls.thread_locals, 'request', None)
-        if request is None:
-            return
-        order_candidates = cls.get_order_candidates()
-        instance = kwargs['instance']
-        order_candidates.add(OrderCandidate(instance, action))
-    
-    def process_request(self, request):
-        """ Store request on a thread local variable """
-        type(self).thread_locals.request = request
-    
-    def process_response(self, request, response):
-        if not isinstance(response, HttpResponseServerError):
-            candidates = type(self).get_order_candidates()
-            Order.process_candidates(candidates)
-        return response

orchestra/apps/orders/models.py

@@ -1,9 +1,15 @@
 from django.db import models
+from django.db.models import Q
+from django.db.models.signals import pre_delete, post_delete, post_save
+from django.dispatch import receiver
+from django.contrib.admin.models import LogEntry
 from django.contrib.contenttypes import generic
 from django.contrib.contenttypes.models import ContentType
+from django.utils import timezone
 from django.utils.translation import ugettext_lazy as _
 
 from . import settings
+from .helpers import search_for_related
 
 
 class Service(models.Model):
@@ -31,6 +37,7 @@ class Service(models.Model):
     model = models.ForeignKey(ContentType, verbose_name=_("model"))
     match = models.CharField(_("match"), max_length=256)
     is_active = models.BooleanField(_("is active"), default=True)
+    # TODO class based Service definition (like ServiceBackend)
     # Billing
     billing_period = models.CharField(_("billing period"), max_length=16,
             help_text=_("Renewal period for recurring invoicing"),
@@ -145,6 +152,7 @@ class Service(models.Model):
 
     @classmethod
     def get_services(cls, instance, **kwargs):
+        # TODO get per-request cache from thread local
         cache = kwargs.get('cache', {})
         ct = ContentType.objects.get_for_model(type(instance))
         try:
@@ -155,11 +163,23 @@ class Service(models.Model):
     
     def matches(self, instance):
         safe_locals = {
-            'instance': instance
+            instance._meta.model_name: instance
         }
         return eval(self.match, safe_locals)
 
 
+class OrderQuerySet(models.QuerySet):
+    def by_object(self, obj, *args, **kwargs):
+        ct = ContentType.objects.get_for_model(obj)
+        return self.filter(object_id=obj.pk, content_type=ct)
+    
+    def active(self, *args, **kwargs):
+        """ return active orders """
+        return self.filter(
+            Q(cancelled_on__isnull=True) | Q(cancelled_on__gt=timezone.now())
+        ).filter(*args, **kwargs)
+
+
 class Order(models.Model):
     SAVE = 'SAVE'
     DELETE = 'DELETE'
@@ -178,6 +198,7 @@ class Order(models.Model):
     description = models.TextField(_("description"), blank=True)
     
     content_object = generic.GenericForeignKey()
+    objects = OrderQuerySet.as_manager()
 
     def __unicode__(self):
         return str(self.service)
@@ -193,33 +214,23 @@ class Order(models.Model):
             self.save()
     
     @classmethod
-    def process_candidates(cls, candidates):
+    def update_orders(cls, instance):
-        cache = {}
+        for service in Service.get_services(instance):
-        for candidate in candidates:
+            orders = Order.objects.by_object(instance, service=service).active()
-            instance = candidate.instance
+            if service.matches(instance):
-            if candidate.action == cls.DELETE:
+                if not orders:
-                cls.objects.filter_for_object(instance).cancel()
+                    account_id = getattr(instance, 'account_id', instance.pk)
-            else:
+                    order = cls.objects.create(content_object=instance,
-                for service in Service.get_services(instance, cache=cache):
+                            service=service, account_id=account_id)
-                    print cache
+                else:
-                    if not instance.pk:
+                    order = orders.get()
-                        if service.matches(instance):
+                order.update()
-                            order = cls.objects.create(content_object=instance,
+            elif orders:
-                                    account_id=instance.account_id, service=service)
+                orders.get().cancel()
-                            order.update()
+    
-                    else:
+    def cancel(self):
-                        ct = ContentType.objects.get_for_model(instance)
+        self.cancelled_on = timezone.now()
-                        orders = cls.objects.filter(content_type=ct, service=service,
+        self.save()
-                                object_id=instance.pk)
-                        if service.matches(instance):
-                            if not orders:
-                                order = cls.objects.create(content_object=instance,
-                                        service=service, account_id=instance.account_id)
-                            else:
-                                order = orders.get()
-                            order.update()
-                        elif orders:
-                            orders.get().cancel()
 
 
 class MetricStorage(models.Model):
@@ -229,3 +240,31 @@ class MetricStorage(models.Model):
     
     def __unicode__(self):
         return self.order
+
+
+
+@receiver(pre_delete, dispatch_uid="orders.cancel_orders")
+def cancel_orders(sender, **kwargs):
+    if not sender in [MetricStorage, LogEntry, Order, Service]:
+        instance = kwargs['instance']
+        for order in Order.objects.by_object(instance).active():
+            order.cancel()
+
+
+@receiver(post_delete, dispatch_uid="orders.update_orders_on_delete")
+def update_orders_on_delete(sender, **kwargs):
+    if not sender in [MetricStorage, LogEntry, Order, Service]:
+        instance = kwargs['instance']
+        related = search_for_related(instance)
+        if related:
+            Order.update_orders(related)
+
+
+@receiver(post_save, dispatch_uid="orders.update_orders")
+def update_orders(sender, **kwargs):
+    if not sender in [MetricStorage, LogEntry, Order, Service]:
+        instance = kwargs['instance']
+        Order.update_orders(instance)
+        related = search_for_related(instance)
+        if related:
+            Order.update_orders(related)

orchestra/apps/resources/admin.py

@@ -47,7 +47,7 @@ class ResourceAdmin(ExtendedModelAdmin):
     def save_model(self, request, obj, form, change):
         super(ResourceAdmin, self).save_model(request, obj, form, change)
         model = obj.content_type.model_class()
-        modeladmin = get_modeladmin(model)
+        modeladmin = type(get_modeladmin(model))
         resources = obj.content_type.resource_set.filter(is_active=True)
         inlines = []
         for inline in modeladmin.inlines:

orchestra/apps/resources/forms.py

@@ -9,8 +9,6 @@ from orchestra.forms.widgets import ShowTextWidget, ReadOnlyWidget
 class ResourceForm(forms.ModelForm):
     verbose_name = forms.CharField(label=_("Name"), widget=ShowTextWidget(bold=True),
             required=False)
-    used = forms.IntegerField(label=_("Used"), widget=ShowTextWidget(),
-            required=False)
     allocated = forms.IntegerField(label=_("Allocated"))
     unit = forms.CharField(label=_("Unit"), widget=ShowTextWidget(), required=False)
     

orchestra/apps/resources/models.py

@@ -161,7 +161,17 @@ class MonitorData(models.Model):
 
 
 def create_resource_relation():
+    class ResourceHandler(object):
+        """ account.resources.web """
+        def __getattr__(self, attr):
+            return self.obj.resource_set.get(resource__name=attr)
+        
+        def __get__(self, obj, cls):
+            self.obj = obj
+            return self
+    
     relation = GenericRelation('resources.ResourceData')
     for resources in Resource.group_by_content_type():
         model = resources[0].content_type.model_class()
-        model.add_to_class('resources', relation)
+        model.add_to_class('resource_set', relation)
+        model.resources = ResourceHandler()

orchestra/apps/users/roles/admin.py

@@ -33,10 +33,10 @@ class RoleAdmin(object):
             return False
     
     def get_user(self, request, object_id):
-        modeladmin = get_modeladmin(User)
+        try:
-        user = modeladmin.get_object(request, unquote(object_id))
+            user = User.objects.get(pk=unquote(object_id))
-        opts = self.model._meta
+        except User.DoesNotExist:
-        if user is None:
+            opts = self.model._meta
             raise Http404(
                 _('%(name)s object with primary key %(key)r does not exist.') %
                 {'name': force_text(opts.verbose_name), 'key': escape(object_id)}
@@ -53,7 +53,7 @@ class RoleAdmin(object):
             obj = getattr(user, self.name)
         form_class = self.form if self.form else role_form_factory(self)
         form = form_class(instance=obj)
-        opts = modeladmin.model._meta
+        opts = User._meta
         app_label = opts.app_label
         title = _("Add %s for user %s" % (self.name, user))
         action = _("Create")

orchestra/bin/orchestra-admin

@@ -128,7 +128,7 @@ function install_requirements () {
          python-cracklib"
     
     PIP="django==1.6.1 \
-         django-celery-email==1.0.3 \
+         django-celery-email==1.0.4 \
          django-fluent-dashboard==0.3.5 \
          https://bitbucket.org/izi/django-admin-tools/get/a0abfffd76a0.zip \
          IPy==0.81 \

orchestra/conf/base_settings.py

@@ -43,7 +43,6 @@ MIDDLEWARE_CLASSES = (
     'django.contrib.auth.middleware.AuthenticationMiddleware',
     'django.contrib.messages.middleware.MessageMiddleware',
     'django.middleware.transaction.TransactionMiddleware',
-    'orchestra.apps.orders.middlewares.OrderMiddleware',
     'orchestra.apps.orchestration.middlewares.OperationsMiddleware',
     # Uncomment the next line for simple clickjacking protection:
     # 'django.middleware.clickjacking.XFrameOptionsMiddleware',