public void bindEIP()

in eureka-core/src/main/java/com/netflix/eureka/aws/EIPManager.java [193:258]
51 lines of code
12 McCabe index (conditional complexity)

    public void bindEIP() {
        InstanceInfo myInfo = applicationInfoManager.getInfo();
        String myInstanceId = ((AmazonInfo) myInfo.getDataCenterInfo()).get(MetaDataKey.instanceId);
        String myZone = ((AmazonInfo) myInfo.getDataCenterInfo()).get(MetaDataKey.availabilityZone);

        Collection<String> candidateEIPs = getCandidateEIPs(myInstanceId, myZone);

        AmazonEC2 ec2Service = getEC2Service();
        boolean isMyinstanceAssociatedWithEIP = false;
        Address selectedEIP = null;

        for (String eipEntry : candidateEIPs) {
            try {
                String associatedInstanceId;

                // Check with AWS, if this EIP is already been used by another instance
                DescribeAddressesRequest describeAddressRequest = new DescribeAddressesRequest().withPublicIps(eipEntry);
                DescribeAddressesResult result = ec2Service.describeAddresses(describeAddressRequest);
                if ((result.getAddresses() != null) && (!result.getAddresses().isEmpty())) {
                    Address eipAddress = result.getAddresses().get(0);
                    associatedInstanceId = eipAddress.getInstanceId();
                    // This EIP is not used by any other instance, hence mark it for selection if it is not
                    // already marked.
                    if (((associatedInstanceId == null) || (associatedInstanceId.isEmpty()))) {
                        if (selectedEIP == null) {
                            selectedEIP = eipAddress;
                        }
                    } else if (isMyinstanceAssociatedWithEIP = (associatedInstanceId.equals(myInstanceId))) {
                        // This EIP is associated with an instance, check if this is the same as the current instance.
                        // If it is the same, stop searching for an EIP as this instance is already associated with an
                        // EIP
                        selectedEIP = eipAddress;
                        break;
                    } else {
                        // The EIP is used by some other instance, hence skip it
                        logger.warn("The selected EIP {} is associated with another instance {} according to AWS," +
                                " hence skipping this", eipEntry, associatedInstanceId);
                    }
                }
            } catch (Throwable t) {
                logger.error("Failed to bind elastic IP: {} to {}", eipEntry, myInstanceId, t);
            }
        }
        if (null != selectedEIP) {
            String publicIp = selectedEIP.getPublicIp();
            // Only bind if the EIP is not already associated
            if (!isMyinstanceAssociatedWithEIP) {

                AssociateAddressRequest associateAddressRequest = new AssociateAddressRequest()
                        .withInstanceId(myInstanceId);

                String domain = selectedEIP.getDomain();
                if ("vpc".equals(domain)) {
                    associateAddressRequest.setAllocationId(selectedEIP.getAllocationId());
                } else {
                    associateAddressRequest.setPublicIp(publicIp);
                }

                ec2Service.associateAddress(associateAddressRequest);
                logger.info("\n\n\nAssociated {} running in zone: {} to elastic IP: {}", myInstanceId, myZone, publicIp);
            }
            logger.info("My instance {} seems to be already associated with the EIP {}", myInstanceId, publicIp);
        } else {
            logger.info("No EIP is free to be associated with this instance. Candidate EIPs are: {}", candidateEIPs);
        }
    }