storage: add new app

storage/admin.py

+from django import contrib
+# from django.utils.translation import ugettext_lazy as _
+
+from .models import Disk, DataStore
+
+
+class DiskAdmin(contrib.admin.ModelAdmin):
+    list_display = ('name', 'datastore')
+
+
+class DataStoreAdmin(contrib.admin.ModelAdmin):
+    list_display = ('name', 'path')
+
+
+contrib.admin.site.register(Disk, DiskAdmin)
+contrib.admin.site.register(DataStore, DataStoreAdmin)

storage/migrations/0001_initial.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding model 'Disk'
+        db.create_table('storage_disk', (
+            ('id', self.gf('django.db.models.fields.AutoField')(primary_key=True)),
+            ('name', self.gf('django.db.models.fields.CharField')(unique=True, max_length=100)),
+            ('path', self.gf('django.db.models.fields.CharField')(unique=True, max_length=200)),
+            ('format', self.gf('django.db.models.fields.CharField')(max_length=10)),
+            ('size', self.gf('django.db.models.fields.IntegerField')()),
+            ('type', self.gf('django.db.models.fields.CharField')(max_length=10)),
+            ('base', self.gf('django.db.models.fields.related.ForeignKey')(related_name='snapshots', to=orm['storage.Disk'])),
+            ('original_parent', self.gf('django.db.models.fields.related.ForeignKey')(to=orm['storage.Disk'])),
+        ))
+        db.send_create_signal('storage', ['Disk'])
+
+
+    def backwards(self, orm):
+        # Deleting model 'Disk'
+        db.delete_table('storage_disk')
+
+
+    models = {
+        'storage.disk': {
+            'Meta': {'ordering': "['name']", 'object_name': 'Disk'},
+            'base': ('django.db.models.fields.related.ForeignKey', [], {'related_name': "'snapshots'", 'to': "orm['storage.Disk']"}),
+            'format': ('django.db.models.fields.CharField', [], {'max_length': '10'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'original_parent': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.Disk']"}),
+            'path': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '200'}),
+            'size': ('django.db.models.fields.IntegerField', [], {}),
+            'type': ('django.db.models.fields.CharField', [], {'max_length': '10'})
+        }
+    }
+
+    complete_apps = ['storage']
\ No newline at end of file

storage/migrations/0002_auto__chg_field_disk_original_parent__chg_field_disk_base.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+
+        # Changing field 'Disk.original_parent'
+        db.alter_column('storage_disk', 'original_parent_id', self.gf('django.db.models.fields.related.ForeignKey')(to=orm['storage.Disk'], null=True))
+
+        # Changing field 'Disk.base'
+        db.alter_column('storage_disk', 'base_id', self.gf('django.db.models.fields.related.ForeignKey')(null=True, to=orm['storage.Disk']))
+
+    def backwards(self, orm):
+
+        # User chose to not deal with backwards NULL issues for 'Disk.original_parent'
+        raise RuntimeError("Cannot reverse this migration. 'Disk.original_parent' and its values cannot be restored.")
+
+        # User chose to not deal with backwards NULL issues for 'Disk.base'
+        raise RuntimeError("Cannot reverse this migration. 'Disk.base' and its values cannot be restored.")
+
+    models = {
+        'storage.disk': {
+            'Meta': {'ordering': "['name']", 'object_name': 'Disk'},
+            'base': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'snapshots'", 'null': 'True', 'to': "orm['storage.Disk']"}),
+            'format': ('django.db.models.fields.CharField', [], {'max_length': '10'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'original_parent': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.Disk']", 'null': 'True', 'blank': 'True'}),
+            'path': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '200'}),
+            'size': ('django.db.models.fields.IntegerField', [], {}),
+            'type': ('django.db.models.fields.CharField', [], {'max_length': '10'})
+        }
+    }
+
+    complete_apps = ['storage']
\ No newline at end of file

storage/migrations/0003_auto__add_datastore__del_field_disk_path__add_field_disk_datastore.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding model 'DataStore'
+        db.create_table('storage_datastore', (
+            ('id', self.gf('django.db.models.fields.AutoField')(primary_key=True)),
+            ('name', self.gf('django.db.models.fields.CharField')(unique=True, max_length=100)),
+            ('path', self.gf('django.db.models.fields.CharField')(unique=True, max_length=200)),
+        ))
+        db.send_create_signal('storage', ['DataStore'])
+
+        # Deleting field 'Disk.path'
+        db.delete_column('storage_disk', 'path')
+
+        # Adding field 'Disk.datastore'
+        db.add_column('storage_disk', 'datastore',
+                      self.gf('django.db.models.fields.related.ForeignKey')(default=None, to=orm['storage.DataStore']),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting model 'DataStore'
+        db.delete_table('storage_datastore')
+
+
+        # User chose to not deal with backwards NULL issues for 'Disk.path'
+        raise RuntimeError("Cannot reverse this migration. 'Disk.path' and its values cannot be restored.")
+        # Deleting field 'Disk.datastore'
+        db.delete_column('storage_disk', 'datastore_id')
+
+
+    models = {
+        'storage.datastore': {
+            'Meta': {'ordering': "['name']", 'object_name': 'DataStore'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'path': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '200'})
+        },
+        'storage.disk': {
+            'Meta': {'ordering': "['name']", 'object_name': 'Disk'},
+            'base': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'snapshots'", 'null': 'True', 'to': "orm['storage.Disk']"}),
+            'datastore': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.DataStore']"}),
+            'format': ('django.db.models.fields.CharField', [], {'max_length': '10'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'original_parent': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.Disk']", 'null': 'True', 'blank': 'True'}),
+            'size': ('django.db.models.fields.IntegerField', [], {}),
+            'type': ('django.db.models.fields.CharField', [], {'max_length': '10'})
+        }
+    }
+
+    complete_apps = ['storage']
\ No newline at end of file

storage/migrations/0004_auto__add_field_disk_created.py

+# -*- coding: utf-8 -*-
+import datetime
+from south.db import db
+from south.v2 import SchemaMigration
+from django.db import models
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Adding field 'Disk.created'
+        db.add_column('storage_disk', 'created',
+                      self.gf('django.db.models.fields.BooleanField')(default=False),
+                      keep_default=False)
+
+
+    def backwards(self, orm):
+        # Deleting field 'Disk.created'
+        db.delete_column('storage_disk', 'created')
+
+
+    models = {
+        'storage.datastore': {
+            'Meta': {'ordering': "['name']", 'object_name': 'DataStore'},
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'path': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '200'})
+        },
+        'storage.disk': {
+            'Meta': {'ordering': "['name']", 'object_name': 'Disk'},
+            'base': ('django.db.models.fields.related.ForeignKey', [], {'blank': 'True', 'related_name': "'snapshots'", 'null': 'True', 'to': "orm['storage.Disk']"}),
+            'created': ('django.db.models.fields.BooleanField', [], {'default': 'False'}),
+            'datastore': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.DataStore']"}),
+            'format': ('django.db.models.fields.CharField', [], {'max_length': '10'}),
+            'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'name': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '100'}),
+            'original_parent': ('django.db.models.fields.related.ForeignKey', [], {'to': "orm['storage.Disk']", 'null': 'True', 'blank': 'True'}),
+            'size': ('django.db.models.fields.IntegerField', [], {}),
+            'type': ('django.db.models.fields.CharField', [], {'max_length': '10'})
+        }
+    }
+
+    complete_apps = ['storage']
\ No newline at end of file

storage/models.py

+# coding=utf-8
+
+import logging
+import jsonpickle
+import json
+from django.db import models, transaction
+from django.utils.translation import ugettext_lazy as _
+from django.db.models.signals import post_save, post_delete
+
+from .tasks import StorageDriver
+
+logger = logging.getLogger(__name__)
+
+
+class DataStore(models.Model):
+    name = models.CharField(max_length=100, unique=True,
+                            verbose_name=_('name'))
+    path = models.CharField(max_length=200, unique=True,
+                            verbose_name=_('path'))
+
+    class Meta:
+        ordering = ['name']
+        verbose_name = _('datastore')
+        verbose_name_plural = _('datastores')
+
+    def __unicode__(self):
+        return u'%s (%s)' % (self.name, self.path)
+
+
+class Disk(models.Model):
+    """Virtual disks automatically synchronized with OpenNebula."""
+    name = models.CharField(max_length=100, unique=True,
+                            verbose_name=_('name'))
+    datastore = models.ForeignKey('DataStore')
+    format = models.CharField(max_length=10,
+                              choices=(('qcow2', 'qcow2'), ('raw', 'raw')))
+    size = models.IntegerField()
+    type = models.CharField(max_length=10,
+                            choices=(('snapshot', 'snapshot'),
+                                     ('normal', 'normal')))
+    base = models.ForeignKey('Disk', related_name='snapshots',
+                             null=True, blank=True)
+    original_parent = models.ForeignKey('Disk', null=True, blank=True)
+    created = models.BooleanField(default=False)
+
+    class Meta:
+        ordering = ['name']
+        verbose_name = _('disk')
+        verbose_name_plural = _('disks')
+
+    def to_json(self):
+        self.base_name = self.base.name if self.base else None
+        self.dir = self.datastore.path
+        return jsonpickle.encode(self, unpicklable=True)
+
+    def __unicode__(self):
+        return u"%s (#%d)" % (self.name, self.id)
+
+    @classmethod
+    def create_signal(cls, sender, instance, created, **kwargs):
+        if not instance.created:
+            StorageDriver.create_disk.delay(instance.to_json()).get()
+            instance.created = True
+            instance.save()
+
+    @classmethod
+    def delete_signal(cls, sender, instance, using, **kwargs):
+        StorageDriver.delete_disk.delay(instance.to_json()).get()
+
+    @classmethod
+    def update_disk(cls, disk):
+        name = disk['name']
+        modified = False
+        try:
+            base = cls.objects.get(name=disk['base_name'])
+        except cls.DoesNotExist:
+            base = None
+
+        try:
+            d = cls.objects.get(name=name)
+        except Disk.DoesNotExist:
+            d = Disk(name=name,
+                     created=True,
+                     datastore=DataStore.objects.get(path=disk['dir']),
+                     format=disk['format'],
+                     type=disk['type'])
+            modified = True
+
+        if d.size != disk['size'] or d.base != base:
+            d.size = disk['size']
+            d.base = base
+            modified = True
+
+        if modified:
+            d.full_clean()
+            d.save()
+
+    @classmethod
+    def update_disks(cls, delete=True):
+        """Get and register virtual disks from OpenNebula."""
+        try:
+            json_data = StorageDriver.list_disks.delay().get(timeout=10)
+            disks = json.loads(json_data)
+        except:
+            return
+        with transaction.commit_on_success():
+            l = []
+            for disk in disks:
+                print disk
+                cls.update_disk(disk)
+                l.append(disk['name'])
+            if delete:
+                cls.objects.exclude(name__in=l).delete()
+
+post_save.connect(Disk.create_signal, sender=Disk)
+post_delete.connect(Disk.delete_signal, sender=Disk)

storage/tasks.py

+import celery
+from celery.contrib.methods import task_method
+
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class StorageDriver:
+    @celery.task(filter=task_method, name='storagedriver.list_disks')
+    def list_disks():
+        pass
+
+    @celery.task(filter=task_method, name='storagedriver.create_disk')
+    def create_disk(json_data):
+        pass
+
+    @celery.task(filter=task_method, name='storagedriver.delete_disk')
+    def delete_disk(json_data):
+        pass
+
+    @celery.task(filter=task_method, name='storagedriver.get_disk')
+    def get_disk(json_data):
+        pass

storage/tests.py

+"""
+This file demonstrates writing tests using the unittest module. These will pass
+when you run "manage.py test".
+
+Replace this with more appropriate tests for your application.
+"""
+
+from django.test import TestCase
+
+
+class SimpleTest(TestCase):
+    def test_basic_addition(self):
+        """
+        Tests that 1 + 1 always equals 2.
+        """
+        self.assertEqual(1 + 1, 2)

storage/views.py

+# Create your views here.