func NewClient()

in client.go [171:233]
51 lines of code
15 McCabe index (conditional complexity)

func NewClient(addrs []string, conf *Config) (Client, error) {
	DebugLogger.Println("Initializing new client")

	if conf == nil {
		conf = NewConfig()
	}

	if err := conf.Validate(); err != nil {
		return nil, err
	}

	if len(addrs) < 1 {
		return nil, ConfigurationError("You must provide at least one broker address")
	}

	if strings.Contains(addrs[0], ".servicebus.windows.net") {
		if conf.Version.IsAtLeast(V1_1_0_0) || !conf.Version.IsAtLeast(V0_11_0_0) {
			Logger.Println("Connecting to Azure Event Hubs, forcing version to V1_0_0_0 for compatibility")
			conf.Version = V1_0_0_0
		}
	}

	client := &client{
		conf:                    conf,
		closer:                  make(chan none),
		closed:                  make(chan none),
		brokers:                 make(map[int32]*Broker),
		metadata:                make(map[string]map[int32]*PartitionMetadata),
		metadataTopics:          make(map[string]none),
		cachedPartitionsResults: make(map[string][maxPartitionIndex][]int32),
		coordinators:            make(map[string]int32),
		transactionCoordinators: make(map[string]int32),
	}

	if conf.Net.ResolveCanonicalBootstrapServers {
		var err error
		addrs, err = client.resolveCanonicalNames(addrs)
		if err != nil {
			return nil, err
		}
	}

	client.randomizeSeedBrokers(addrs)

	if conf.Metadata.Full {
		// do an initial fetch of all cluster metadata by specifying an empty list of topics
		err := client.RefreshMetadata()
		if err == nil {
		} else if errors.Is(err, ErrLeaderNotAvailable) || errors.Is(err, ErrReplicaNotAvailable) || errors.Is(err, ErrTopicAuthorizationFailed) || errors.Is(err, ErrClusterAuthorizationFailed) {
			// indicates that maybe part of the cluster is down, but is not fatal to creating the client
			Logger.Println(err)
		} else {
			close(client.closed) // we haven't started the background updater yet, so we have to do this manually
			_ = client.Close()
			return nil, err
		}
	}
	go withRecover(client.backgroundMetadataUpdater)

	DebugLogger.Println("Successfully initialized new client")

	return client, nil
}