func()

in cloudstack_loadbalancer.go [76:200]
97 lines of code
27 McCabe index (conditional complexity)

func (cs *CSCloud) EnsureLoadBalancer(ctx context.Context, clusterName string, service *corev1.Service, nodes []*corev1.Node) (status *corev1.LoadBalancerStatus, err error) {
	klog.V(4).Infof("EnsureLoadBalancer(%v, %v, %v, %v, %v, %v)", clusterName, service.Namespace, service.Name, service.Spec.LoadBalancerIP, service.Spec.Ports, nodes)

	if len(service.Spec.Ports) == 0 {
		return nil, fmt.Errorf("requested load balancer with no ports")
	}

	// Get the load balancer details and existing rules.
	lb, err := cs.getLoadBalancer(service)
	if err != nil {
		return nil, err
	}

	// Set the load balancer algorithm.
	switch service.Spec.SessionAffinity {
	case corev1.ServiceAffinityNone:
		lb.algorithm = "roundrobin"
	case corev1.ServiceAffinityClientIP:
		lb.algorithm = "source"
	default:
		return nil, fmt.Errorf("unsupported load balancer affinity: %v", service.Spec.SessionAffinity)
	}

	// Verify that all the hosts belong to the same network, and retrieve their ID's.
	lb.hostIDs, lb.networkID, err = cs.verifyHosts(nodes)
	if err != nil {
		return nil, err
	}

	if !lb.hasLoadBalancerIP() {
		// Create or retrieve the load balancer IP.
		if err := lb.getLoadBalancerIP(service.Spec.LoadBalancerIP); err != nil {
			return nil, err
		}

		if lb.ipAddr != "" && lb.ipAddr != service.Spec.LoadBalancerIP {
			defer func(lb *loadBalancer) {
				if err != nil {
					if err := lb.releaseLoadBalancerIP(); err != nil {
						klog.Errorf(err.Error())
					}
				}
			}(lb)
		}
	}

	klog.V(4).Infof("Load balancer %v is associated with IP %v", lb.name, lb.ipAddr)

	for _, port := range service.Spec.Ports {
		// Construct the protocol name first, we need it a few times
		protocol := ProtocolFromServicePort(port, service.Annotations)
		if protocol == LoadBalancerProtocolInvalid {
			return nil, fmt.Errorf("unsupported load balancer protocol: %v", port.Protocol)
		}

		// All ports have their own load balancer rule, so add the port to lbName to keep the names unique.
		lbRuleName := fmt.Sprintf("%s-%s-%d", lb.name, protocol, port.Port)

		// If the load balancer rule exists and is up-to-date, we move on to the next rule.
		lbRule, needsUpdate, err := lb.checkLoadBalancerRule(lbRuleName, port, protocol)
		if err != nil {
			return nil, err
		}

		if lbRule != nil {
			if needsUpdate {
				klog.V(4).Infof("Updating load balancer rule: %v", lbRuleName)
				if err := lb.updateLoadBalancerRule(lbRuleName, protocol); err != nil {
					return nil, err
				}
				// Delete the rule from the map, to prevent it being deleted.
				delete(lb.rules, lbRuleName)
			} else {
				klog.V(4).Infof("Load balancer rule %v is up-to-date", lbRuleName)
				// Delete the rule from the map, to prevent it being deleted.
				delete(lb.rules, lbRuleName)
			}
		} else {
			klog.V(4).Infof("Creating load balancer rule: %v", lbRuleName)
			lbRule, err = lb.createLoadBalancerRule(lbRuleName, port, protocol)
			if err != nil {
				return nil, err
			}

			klog.V(4).Infof("Assigning hosts (%v) to load balancer rule: %v", lb.hostIDs, lbRuleName)
			if err = lb.assignHostsToRule(lbRule, lb.hostIDs); err != nil {
				return nil, err
			}
		}

		if lbRule != nil {
			klog.V(4).Infof("Creating firewall rules for load balancer rule: %v (%v:%v:%v)", lbRuleName, protocol, lbRule.Publicip, port.Port)
			if _, err := lb.updateFirewallRule(lbRule.Publicipid, int(port.Port), protocol, service.Spec.LoadBalancerSourceRanges); err != nil {
				return nil, err
			}
		}
	}

	// Cleanup any rules that are now still in the rules map, as they are no longer needed.
	for _, lbRule := range lb.rules {
		protocol := ProtocolFromLoadBalancer(lbRule.Protocol)
		if protocol == LoadBalancerProtocolInvalid {
			return nil, fmt.Errorf("Error parsing protocol %v: %v", lbRule.Protocol, err)
		}
		port, err := strconv.ParseInt(lbRule.Publicport, 10, 32)
		if err != nil {
			return nil, fmt.Errorf("Error parsing port %s: %v", lbRule.Publicport, err)
		}

		klog.V(4).Infof("Deleting firewall rules associated with load balancer rule: %v (%v:%v:%v)", lbRule.Name, protocol, lbRule.Publicip, port)
		if _, err := lb.deleteFirewallRule(lbRule.Publicipid, int(port), protocol); err != nil {
			return nil, err
		}

		klog.V(4).Infof("Deleting obsolete load balancer rule: %v", lbRule.Name)
		if err := lb.deleteLoadBalancerRule(lbRule); err != nil {
			return nil, err
		}
	}

	status = &corev1.LoadBalancerStatus{}
	status.Ingress = []corev1.LoadBalancerIngress{{IP: lb.ipAddr}}

	return status, nil
}