def _run_instance(cluster, node_group, idx, aa_groups, userdata):
"""Create instance using nova client and persist them into DB."""
session = context.ctx().session
name = '%s-%s-%03d' % (cluster.name, node_group.name, idx)
# aa_groups: node process -> instance ids
aa_ids = []
for node_process in node_group.node_processes:
aa_ids += aa_groups.get(node_process) or []
# create instances only at hosts w/ no instances w/ aa-enabled processes
hints = {'different_host': list(set(aa_ids))} if aa_ids else None
context.model_save(node_group)
nova_instance = nova.client().servers.create(
name, node_group.get_image_id(), node_group.flavor_id,
scheduler_hints=hints, userdata=userdata,
key_name=cluster.user_keypair_id)
with session.begin():
instance = m.Instance(node_group.id, nova_instance.id, name)
node_group.instances.append(instance)
session.add(instance)
# save instance id to aa_groups to support aa feature
for node_process in node_group.node_processes:
if node_process in cluster.anti_affinity:
aa_group_ids = aa_groups.get(node_process, [])
aa_group_ids.append(nova_instance.id)
aa_groups[node_process] = aa_group_ids
return instance
def scale_cluster(cluster_id, data):
cluster = get_cluster(id=cluster_id)
plugin = plugin_base.PLUGINS.get_plugin(cluster.plugin_name)
existing_node_groups = data.get("resize_node_groups", [])
additional_node_groups = data.get("add_node_groups", [])
# the next map is the main object we will work with
# to_be_enlarged : {node_group_name: desired_amount_of_instances}
to_be_enlarged = {}
for ng in existing_node_groups:
to_be_enlarged.update({ng["name"]: ng["count"]})
additional = construct_ngs_for_scaling(additional_node_groups)
try:
context.model_update(cluster, status="Validating")
plugin.validate_scaling(cluster, to_be_enlarged, additional)
except Exception:
with excutils.save_and_reraise_exception():
context.model_update(cluster, status="Active")
# If we are here validation is successful.
# So let's update bd and to_be_enlarged map:
for add_n_g in additional:
cluster.node_groups.append(add_n_g)
to_be_enlarged.update({add_n_g.name: additional[add_n_g]})
context.model_save(cluster)
context.spawn(_provision_nodes, cluster_id, to_be_enlarged)
return cluster
def _scale_cluster_instances(cluster, node_groups_map, plugin):
aa_groups = _generate_anti_affinity_groups(cluster)
instances_to_delete = []
node_groups_to_enlarge = []
for node_group in node_groups_map:
count = node_groups_map[node_group]
if count < node_group.count:
instances_to_delete += node_group.instances[count:node_group.count]
else:
node_groups_to_enlarge.append(node_group)
if instances_to_delete:
cluster.status = 'Decommissioning'
plugin.decommission_nodes(cluster, instances_to_delete)
cluster.status = 'Deleting Instances'
for instance in instances_to_delete:
node_group = instance.node_group
node_group.instances.remove(instance)
_shutdown_instance(instance)
node_group.count -= 1
context.model_save(node_group)
instances_to_add = []
if node_groups_to_enlarge:
cluster.status = 'Adding Instances'
for node_group in node_groups_to_enlarge:
count = node_groups_map[node_group]
userdata = _generate_user_data_script(node_group)
for idx in xrange(node_group.count + 1, count + 1):
instance = _run_instance(cluster, node_group, idx,
aa_groups, userdata)
instances_to_add.append(instance)
node_group.count = count
return instances_to_add
def _insert_test_object():
t = TestModel()
t.test_field = 123
context.model_save(t)
return t
