Cells: Re-add DB model and calls

Implements blueprint nova-compute-cells

Change-Id: I5e254988f3dd17cd1147b6c2d0372e3bb6fe6937

4 files changed, 107 insertions, 0 deletions

diff --git a/nova/db/api.py b/nova/db/api.py
index 37acffaf0..ebad6ffae 100644
--- a/nova/db/api.py
+++ b/nova/db/api.py
@@ -1300,6 +1300,34 @@ def instance_type_access_remove(context, flavor_id, project_id):
 ####################
 
 
+def cell_create(context, values):
+    """Create a new child Cell entry."""
+    return IMPL.cell_create(context, values)
+
+
+def cell_update(context, cell_id, values):
+    """Update a child Cell entry."""
+    return IMPL.cell_update(context, cell_id, values)
+
+
+def cell_delete(context, cell_id):
+    """Delete a child Cell."""
+    return IMPL.cell_delete(context, cell_id)
+
+
+def cell_get(context, cell_id):
+    """Get a specific child Cell."""
+    return IMPL.cell_get(context, cell_id)
+
+
+def cell_get_all(context):
+    """Get all child Cells."""
+    return IMPL.cell_get_all(context)
+
+
+####################
+
+
 def instance_metadata_get(context, instance_uuid):
     """Get all metadata for an instance."""
     return IMPL.instance_metadata_get(context, instance_uuid)
diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index e1d44b727..96666079a 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -3732,6 +3732,53 @@ def instance_type_access_remove(context, flavor_id, project_id):
                                                  project_id=project_id)
 
 
+####################
+
+
+@require_admin_context
+def cell_create(context, values):
+    cell = models.Cell()
+    cell.update(values)
+    cell.save()
+    return cell
+
+
+def _cell_get_by_id_query(context, cell_id, session=None):
+    return model_query(context, models.Cell, session=session).\
+                       filter_by(id=cell_id)
+
+
+@require_admin_context
+def cell_update(context, cell_id, values):
+    cell = cell_get(context, cell_id)
+    cell.update(values)
+    cell.save()
+    return cell
+
+
+@require_admin_context
+def cell_delete(context, cell_id):
+    session = get_session()
+    with session.begin():
+        return _cell_get_by_id_query(context, cell_id, session=session).\
+                delete()
+
+
+@require_admin_context
+def cell_get(context, cell_id):
+    result = _cell_get_by_id_query(context, cell_id).first()
+
+    if not result:
+        raise exception.CellNotFound(cell_id=cell_id)
+
+    return result
+
+
+@require_admin_context
+def cell_get_all(context):
+    return model_query(context, models.Cell, read_deleted="no").all()
+
+
 ########################
 # User-provided metadata
 
diff --git a/nova/db/sqlalchemy/models.py b/nova/db/sqlalchemy/models.py
index 5716f9ecd..12a1e7e74 100644
--- a/nova/db/sqlalchemy/models.py
+++ b/nova/db/sqlalchemy/models.py
@@ -306,6 +306,10 @@ class Instance(BASE, NovaBase):
     # EC2 disable_api_termination
     disable_terminate = Column(Boolean(), default=False, nullable=False)
 
+    # OpenStack compute cell name.  This will only be set at the top of
+    # the cells tree and it'll be a full cell name such as 'api!hop1!hop2'
+    cell_name = Column(String(255))
+
 
 class InstanceInfoCache(BASE, NovaBase):
     """
@@ -821,6 +825,30 @@ class InstanceTypeExtraSpecs(BASE, NovaBase):
                  'InstanceTypeExtraSpecs.deleted == False)')
 
 
+class Cell(BASE, NovaBase):
+    """Represents parent and child cells of this cell.  Cells can
+    have multiple parents and children, so there could be any number
+    of entries with is_parent=True or False
+    """
+    __tablename__ = 'cells'
+    id = Column(Integer, primary_key=True)
+    # Name here is the 'short name' of a cell.  For instance: 'child1'
+    name = Column(String(255))
+    api_url = Column(String(255))
+    # FIXME(comstud): username and password refer to the credentials
+    # used for talking with the AMQP server within a particular cell.
+    # This table needs cleanup to support more generic cells
+    # communication (including via 0mq, for instance)
+    username = Column(String(255))
+    password = Column(String(255))
+    weight_offset = Column(Float(), default=0.0)
+    weight_scale = Column(Float(), default=1.0)
+    is_parent = Column(Boolean())
+    rpc_host = Column(String(255))
+    rpc_port = Column(Integer())
+    rpc_virtual_host = Column(String(255))
+
+
 class AggregateHost(BASE, NovaBase):
     """Represents a host that is member of an aggregate."""
     __tablename__ = 'aggregate_hosts'
diff --git a/nova/exception.py b/nova/exception.py
index 54b3a17cc..2ba11ac32 100644
--- a/nova/exception.py
+++ b/nova/exception.py
@@ -753,6 +753,10 @@ class FlavorAccessNotFound(NotFound):
                 "%(project_id) combination.")
 
 
+class CellNotFound(NotFound):
+    message = _("Cell %(cell_id)s could not be found.")
+
+
 class SchedulerHostFilterNotFound(NotFound):
     message = _("Scheduler Host Filter %(filter_name)s could not be found.")