Golang ServicePortName.String方法代码示例

func tryConnect(service proxy.ServicePortName, srcAddr net.Addr, protocol string, proxier *Proxier) (out net.Conn, err error) {
	for _, retryTimeout := range endpointDialTimeout {
		endpoint, err := proxier.loadBalancer.NextEndpoint(service, srcAddr)
		if err != nil {
			glog.Errorf("Couldn't find an endpoint for %s: %v", service, err)
			return nil, err
		}
		glog.V(3).Infof("Mapped service %q to endpoint %s", service, endpoint)

		// TODO: This could spin up a new goroutine to make the outbound connection,
		// and keep accepting inbound traffic.
		outConn, err := net.DialTimeout(protocol, endpoint, retryTimeout*time.Second)
		if err != nil {
			if isTooManyFDsError(err) {
				panic("Dial failed: " + err.Error())
			}
			glog.Errorf("Dial failed: %v", err)
			continue
		}

		// Count transaction.
		// TODO: For the first time, if dial timed out, should it be handled to indicate the service is not in the map.
		proxier.TransactionCounter.Count(service.String(), endpoint)
		return outConn, nil
	}
	return nil, fmt.Errorf("failed to connect to an endpoint.")
}

// Build a slice of iptables args that are common to from-container and from-host portal rules.
func iptablesCommonPortalArgs(destIP net.IP, addPhysicalInterfaceMatch bool, addDstLocalMatch bool, destPort int, protocol api.Protocol, service proxy.ServicePortName) []string {
	// This list needs to include all fields as they are eventually spit out
	// by iptables-save.  This is because some systems do not support the
	// 'iptables -C' arg, and so fall back on parsing iptables-save output.
	// If this does not match, it will not pass the check.  For example:
	// adding the /32 on the destination IP arg is not strictly required,
	// but causes this list to not match the final iptables-save output.
	// This is fragile and I hope one day we can stop supporting such old
	// iptables versions.
	args := []string{
		"-m", "comment",
		"--comment", service.String(),
		"-p", strings.ToLower(string(protocol)),
		"-m", strings.ToLower(string(protocol)),
		"--dport", fmt.Sprintf("%d", destPort),
	}

	if destIP != nil {
		args = append(args, "-d", fmt.Sprintf("%s/32", destIP.String()))
	}

	if addPhysicalInterfaceMatch {
		args = append(args, "-m", "physdev", "!", "--physdev-is-in")
	}

	if addDstLocalMatch {
		args = append(args, "-m", "addrtype", "--dst-type", "LOCAL")
	}

	return args
}

// This is the same as servicePortChainName but with the endpoint included.
func servicePortEndpointChainName(s proxy.ServicePortName, protocol string, endpoint string) utiliptables.Chain {
	hash := sha256.Sum256([]byte(s.String() + protocol + endpoint))
	encoded := base32.StdEncoding.EncodeToString(hash[:])
	return utiliptables.Chain("KUBE-SEP-" + encoded[:16])
}

// this is the same as servicePortToServiceChain but with the endpoint included essentially
func servicePortAndEndpointToServiceChain(s proxy.ServicePortName, endpoint string) utiliptables.Chain {
	hash := sha256.Sum256([]byte(s.String() + "_" + endpoint))
	encoded := base32.StdEncoding.EncodeToString(hash[:])
	return utiliptables.Chain("KUBE-SEP-" + encoded[:19])
}

// servicePortToServiceChain takes the ServicePortName for a
// service and returns the associated iptables chain
// this is computed by hashing (sha256) then encoding to base64 and
// truncating with the prefix "KUBE-SVC-"
// We do this because Iptables Chain Names must be <= 28 chars long
func servicePortToServiceChain(s proxy.ServicePortName) utiliptables.Chain {
	hash := sha256.Sum256([]byte(s.String()))
	encoded := base32.StdEncoding.EncodeToString(hash[:])
	return utiliptables.Chain("KUBE-SVC-" + encoded[:19])
}

// Build a slice of iptables args for an from-non-local public-port rule.
func (proxier *Proxier) iptablesNonLocalNodePortArgs(nodePort int, protocol api.Protocol, proxyIP net.IP, proxyPort int, service proxy.ServicePortName) []string {
	args := iptablesCommonPortalArgs(nil, false, false, proxyPort, protocol, service)
	args = append(args, "-m", "comment", "--comment", service.String(), "-m", "state", "--state", "NEW", "-j", "ACCEPT")
	return args
}

// portProtoHash takes the ServicePortName and protocol for a service
// returns the associated 16 character hash. This is computed by hashing (sha256)
// then encoding to base32 and truncating to 16 chars. We do this because IPTables
// Chain Names must be <= 28 chars long, and the longer they are the harder they are to read.
func portProtoHash(s proxy.ServicePortName, protocol string) string {
	hash := sha256.Sum256([]byte(s.String() + protocol))
	encoded := base32.StdEncoding.EncodeToString(hash[:])
	return encoded[:16]
}