func()

in pkg/awsutils/awsutils.go [1773:1837]
53 lines of code
14 McCabe index (conditional complexity)

func (cache *EC2InstanceMetadataCache) waitForENIAndIPsAttached(eni string, wantedCidrs int, maxBackoffDelay time.Duration) (eniMetadata ENIMetadata, err error) {
	start := time.Now()
	attempt := 0
	// Wait until the ENI shows up in the instance metadata service and has at least some secondary IPs
	err = retry.NWithBackoff(retry.NewSimpleBackoff(time.Millisecond*100, maxBackoffDelay, 0.15, 2.0), maxENIEC2APIRetries, func() error {
		attempt++
		enis, err := cache.GetAttachedENIs()
		if err != nil {
			log.Warnf("Failed to increase pool, error trying to discover attached ENIs on attempt %d/%d: %v ", attempt, maxENIEC2APIRetries, err)
			return ErrNoNetworkInterfaces
		}
		// Verify that the ENI we are waiting for is in the returned list
		for _, returnedENI := range enis {
			if eni == returnedENI.ENIID {
				// Check how many Secondary IPs or Prefixes have been attached
				var eniIPCount int
				log.Debugf("ENI ID: %v IP Addr: %s, IPv4Prefixes:- %v, IPv6Prefixes:- %v", returnedENI.ENIID,
					returnedENI.IPv4Addresses, returnedENI.IPv4Prefixes, returnedENI.IPv6Prefixes)
				if cache.enablePrefixDelegation {
					eniIPCount = len(returnedENI.IPv4Prefixes)
					if cache.v6Enabled {
						eniIPCount = len(returnedENI.IPv6Prefixes)
					}
				} else {
					//Ignore primary IP of the ENI
					//wantedCidrs will be at most 1 less then the IP limit for the ENI because of the primary IP in secondary pod
					eniIPCount = len(returnedENI.IPv4Addresses) - 1
				}

				if eniIPCount < 1 {
					log.Debugf("No secondary IPv4 addresses/prefixes available yet on ENI %s", returnedENI.ENIID)
					return ErrNoSecondaryIPsFound
				}

				// At least some are attached
				eniMetadata = returnedENI

				if eniIPCount >= wantedCidrs {
					return nil
				}
				return ErrAllSecondaryIPsNotFound
			}
		}
		log.Debugf("Not able to find the right ENI yet (attempt %d/%d)", attempt, maxENIEC2APIRetries)
		return ErrENINotFound
	})
	prometheusmetrics.AwsAPILatency.WithLabelValues("waitForENIAndIPsAttached", fmt.Sprint(err != nil), awsReqStatus(err)).Observe(msSince(start))
	if err != nil {
		// If we have at least 1 Secondary IP, by now return what we have without an error
		if err == ErrAllSecondaryIPsNotFound {
			if !cache.enablePrefixDelegation && len(eniMetadata.IPv4Addresses) > 1 {
				// We have some Secondary IPs, return the ones we have
				log.Warnf("This ENI only has %d IP addresses, we wanted %d", len(eniMetadata.IPv4Addresses), wantedCidrs)
				return eniMetadata, nil
			} else if cache.enablePrefixDelegation && len(eniMetadata.IPv4Prefixes) > 1 {
				// We have some prefixes, return the ones we have
				log.Warnf("This ENI only has %d Prefixes, we wanted %d", len(eniMetadata.IPv4Prefixes), wantedCidrs)
				return eniMetadata, nil
			}
		}
		awsAPIErrInc("waitENIAttachedFailedToAssignIPs", err)
		return ENIMetadata{}, errors.New("waitForENIAndIPsAttached: giving up trying to retrieve ENIs from metadata service")
	}
	return eniMetadata, nil
}