func()

in config/reference_config.go [169:301]

• 100 lines of code
• 21 McCabe index (conditional complexity)

func (rc *ReferenceConfig) Refer(srv any) {
	// If adaptive service is enabled,
	// the cluster and load balance should be overridden to "adaptivesvc" and "p2c" respectively.
	if rc.rootConfig.Consumer.AdaptiveService {
		rc.Cluster = constant.ClusterKeyAdaptiveService
		rc.Loadbalance = constant.LoadBalanceKeyP2C
	}

	// cfgURL is an interface-level invoker url, in the other words, it represents an interface.
	cfgURL := common.NewURLWithOptions(
		common.WithPath(rc.InterfaceName),
		common.WithProtocol(rc.Protocol),
		common.WithParams(rc.getURLMap()),
		common.WithParamsValue(constant.BeanNameKey, rc.id),
		common.WithParamsValue(constant.MetadataTypeKey, rc.metaDataType),
	)

	SetConsumerServiceByInterfaceName(rc.InterfaceName, srv)
	if rc.ForceTag {
		cfgURL.AddParam(constant.ForceUseTag, "true")
	}
	rc.postProcessConfig(cfgURL)

	// if mesh-enabled is set
	updateOrCreateMeshURL(rc)

	// retrieving urls from config, and appending the urls to rc.urls
	if rc.URL != "" { // use user-specific urls
		/*
			 Two types of URL are allowed for rc.URL:
				1. direct url: server IP, that is, no need for a registry anymore
				2. registry url
			 They will be handled in different ways:
			 For example, we have a direct url and a registry url:
				1. "tri://localhost:10000" is a direct url
				2. "registry://localhost:2181" is a registry url.
			 Then, rc.URL looks like a string separated by semicolon: "tri://localhost:10000;registry://localhost:2181".
			 The result of urlStrings is a string array: []string{"tri://localhost:10000", "registry://localhost:2181"}.
		*/
		urlStrings := gxstrings.RegSplit(rc.URL, "\\s*[;]+\\s*")
		for _, urlStr := range urlStrings {
			serviceURL, err := common.NewURL(urlStr)
			if err != nil {
				panic(fmt.Sprintf("url configuration error,  please check your configuration, user specified URL %v refer error, error message is %v ", urlStr, err.Error()))
			}
			if serviceURL.Protocol == constant.RegistryProtocol { // serviceURL in this branch is a registry protocol
				serviceURL.SubURL = cfgURL
				rc.urls = append(rc.urls, serviceURL)
			} else { // serviceURL in this branch is the target endpoint IP address
				if serviceURL.Path == "" {
					serviceURL.Path = "/" + rc.InterfaceName
				}
				// replace params of serviceURL with params of cfgUrl
				// other stuff, e.g. IP, port, etc., are same as serviceURL
				newURL := serviceURL.MergeURL(cfgURL)
				newURL.AddParam("peer", "true")
				rc.urls = append(rc.urls, newURL)
			}
		}
	} else { // use registry configs
		rc.urls = LoadRegistries(rc.RegistryIDs, rc.rootConfig.Registries, common.CONSUMER)
		// set url to regURLs
		for _, regURL := range rc.urls {
			regURL.SubURL = cfgURL
		}
	}

	// Get invokers according to rc.urls
	var (
		invoker protocol.Invoker
		regURL  *common.URL
	)
	invokers := make([]protocol.Invoker, len(rc.urls))
	for i, u := range rc.urls {
		if u.Protocol == constant.ServiceRegistryProtocol {
			invoker = extension.GetProtocol(constant.RegistryProtocol).Refer(u)
		} else {
			invoker = extension.GetProtocol(u.Protocol).Refer(u)
		}

		if rc.URL != "" {
			invoker = protocolwrapper.BuildInvokerChain(invoker, constant.ReferenceFilterKey)
		}

		invokers[i] = invoker
		if u.Protocol == constant.RegistryProtocol {
			regURL = u
		}
	}

	// TODO(hxmhlt): decouple from directory, config should not depend on directory module
	if len(invokers) == 1 {
		rc.invoker = invokers[0]
		if rc.URL != "" {
			hitClu := constant.ClusterKeyFailover
			if u := rc.invoker.GetURL(); u != nil {
				hitClu = u.GetParam(constant.ClusterKey, constant.ClusterKeyZoneAware)
			}
			cluster, err := extension.GetCluster(hitClu)
			if err != nil {
				panic(err)
			} else {
				rc.invoker = cluster.Join(static.NewDirectory(invokers))
			}
		}
	} else {
		var hitClu string
		if regURL != nil {
			// for multi-subscription scenario, use 'zone-aware' policy by default
			hitClu = constant.ClusterKeyZoneAware
		} else {
			// not a registry url, must be direct invoke.
			hitClu = constant.ClusterKeyFailover
			if u := invokers[0].GetURL(); u != nil {
				hitClu = u.GetParam(constant.ClusterKey, constant.ClusterKeyZoneAware)
			}
		}
		cluster, err := extension.GetCluster(hitClu)
		if err != nil {
			panic(err)
		} else {
			rc.invoker = cluster.Join(static.NewDirectory(invokers))
		}
	}

	// create proxy
	if rc.Async {
		callback := GetCallback(rc.id)
		rc.pxy = extension.GetProxyFactory(rc.rootConfig.Consumer.ProxyFactory).GetAsyncProxy(rc.invoker, callback, cfgURL)
	} else {
		rc.pxy = extension.GetProxyFactory(rc.rootConfig.Consumer.ProxyFactory).GetProxy(rc.invoker, cfgURL)
	}
}