def a4c_scale(ctx, node_id, delta, scale_compute, **kwargs):
scaled_node = ctx.get_node(node_id)
if not scaled_node:
raise ValueError("Node {0} doesn't exist".format(node_id))
if not is_host_node(scaled_node):
raise ValueError("Node {0} is not a host. This workflow can only scale hosts".format(node_id))
if delta == 0:
ctx.logger.info('delta parameter is 0, so no scaling will take place.')
return
curr_num_instances = scaled_node.number_of_instances
planned_num_instances = curr_num_instances + delta
if planned_num_instances < 1:
raise ValueError('Provided delta: {0} is illegal. current number of'
'instances of node {1} is {2}'
.format(delta, node_id, curr_num_instances))
modification = ctx.deployment.start_modification({
scaled_node.id: {
'instances': planned_num_instances
}
})
ctx.logger.info(
'Deployment modification started. [modification_id={0} : {1}]'.format(modification.id, dir(modification)))
try:
if delta > 0:
ctx.logger.info('Scaling host {0} adding {1} instances'.format(node_id, delta))
added_and_related = _get_all_nodes(modification.added)
added = _get_all_modified_node_instances(added_and_related, 'added')
graph = ctx.graph_mode()
ctx.internal.send_workflow_event(event_type='a4c_workflow_started',
message=build_pre_event(WfStartEvent('scale', 'install')))
custom_context = CustomContext(ctx, added, added_and_related)
install_host(ctx, graph, custom_context, node_id)
try:
graph.execute()
except:
ctx.logger.error('Scale failed. Uninstalling node {0}'.format(node_id))
graph = ctx.internal.task_graph
for task in graph.tasks_iter():
graph.remove_task(task)
try:
custom_context = CustomContext(ctx, added, added_and_related)
uninstall_host(ctx, graph, custom_context, node_id)
graph.execute()
except:
ctx.logger.error('Node {0} uninstallation following scale failure has failed'.format(node_id))
raise
else:
ctx.logger.info('Unscaling host {0} removing {1} instances'.format(node_id, delta))
removed_and_related = _get_all_nodes(modification.removed)
removed = _get_all_modified_node_instances(removed_and_related, 'removed')
graph = ctx.graph_mode()
ctx.internal.send_workflow_event(event_type='a4c_workflow_started',
message=build_pre_event(WfStartEvent('scale', 'uninstall')))
custom_context = CustomContext(ctx, removed, removed_and_related)
uninstall_host(ctx, graph, custom_context, node_id)
try:
graph.execute()
except:
ctx.logger.error('Unscale failed.')
raise
except:
ctx.logger.warn('Rolling back deployment modification. [modification_id={0}]'.format(modification.id))
try:
modification.rollback()
except:
ctx.logger.warn('Deployment modification rollback failed. The '
'deployment model is most likely in some corrupted'
' state.'
'[modification_id={0}]'.format(modification.id))
raise
raise
else:
try:
modification.finish()
except:
ctx.logger.warn('Deployment modification finish failed. The '
'deployment model is most likely in some corrupted'
' state.'
'[modification_id={0}]'.format(modification.id))
raise
def a4c_scale(ctx, node_id, delta, scale_compute, **kwargs):
scaled_node = ctx.get_node(node_id)
if not scaled_node:
raise ValueError("Node {0} doesn't exist".format(node_id))
if not is_host_node(scaled_node):
raise ValueError(
"Node {0} is not a host. This workflow can only scale hosts".
format(node_id))
if delta == 0:
ctx.logger.info('delta parameter is 0, so no scaling will take place.')
return
curr_num_instances = scaled_node.number_of_instances
planned_num_instances = curr_num_instances + delta
if planned_num_instances < 1:
raise ValueError('Provided delta: {0} is illegal. current number of'
'instances of node {1} is {2}'.format(
delta, node_id, curr_num_instances))
modification = ctx.deployment.start_modification(
{scaled_node.id: {
'instances': planned_num_instances
}})
ctx.logger.info(
'Deployment modification started. [modification_id={0} : {1}]'.format(
modification.id, dir(modification)))
try:
if delta > 0:
ctx.logger.info('Scaling host {0} adding {1} instances'.format(
node_id, delta))
added_and_related = _get_all_nodes(modification.added)
added = _get_all_modified_node_instances(added_and_related,
'added')
graph = ctx.graph_mode()
ctx.internal.send_workflow_event(
event_type='a4c_workflow_started',
message=build_pre_event(WfStartEvent('scale', 'install')))
custom_context = CustomContext(ctx, added, added_and_related)
install_host(ctx, graph, custom_context, node_id)
try:
graph.execute()
except:
ctx.logger.error(
'Scale failed. Uninstalling node {0}'.format(node_id))
graph = ctx.internal.task_graph
for task in graph.tasks_iter():
graph.remove_task(task)
try:
custom_context = CustomContext(ctx, added,
added_and_related)
uninstall_host(ctx, graph, custom_context, node_id)
graph.execute()
except:
ctx.logger.error(
'Node {0} uninstallation following scale failure has failed'
.format(node_id))
raise
else:
ctx.logger.info('Unscaling host {0} removing {1} instances'.format(
node_id, delta))
removed_and_related = _get_all_nodes(modification.removed)
removed = _get_all_modified_node_instances(removed_and_related,
'removed')
graph = ctx.graph_mode()
ctx.internal.send_workflow_event(
event_type='a4c_workflow_started',
message=build_pre_event(WfStartEvent('scale', 'uninstall')))
custom_context = CustomContext(ctx, removed, removed_and_related)
uninstall_host(ctx, graph, custom_context, node_id)
try:
graph.execute()
except:
ctx.logger.error('Unscale failed.')
raise
except:
ctx.logger.warn(
'Rolling back deployment modification. [modification_id={0}]'.
format(modification.id))
try:
modification.rollback()
except:
ctx.logger.warn('Deployment modification rollback failed. The '
'deployment model is most likely in some corrupted'
' state.'
'[modification_id={0}]'.format(modification.id))
raise
raise
else:
try:
modification.finish()
except:
ctx.logger.warn('Deployment modification finish failed. The '
'deployment model is most likely in some corrupted'
' state.'
'[modification_id={0}]'.format(modification.id))
raise
