You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: subscribe.go
    path of file: ./repos/seaweedfs/weed/mq/client/sub_client
    
    the code of the file until where you have to start completion: package sub_client

import (
	"fmt"
	"github.com/seaweedfs/seaweedfs/weed/util"
	"io"
	"log"
	"time"
)

// Subscribe subscribes to a topic's specified partitions.
// If a partition is moved to another broker, the subscriber will automatically reconnect to the new broker.

func (sub *TopicSubscriber) Subscribe() error {
	index := -1
	util.RetryUntil("subscribe", func() error {
		index++
		index = index % len(sub.bootstrapBrokers)
		// ask balancer for brokers of the topic
		if err := sub.doLookup(sub.bootstrapBrokers[index]); err != nil {
			return fmt.Errorf("lookup topic %s/%s: %v", sub.ContentConfig.Namespace, sub.ContentConfig.Topic, err)
		}
		if len(sub.brokerPartitionAssignments) == 0 {
			if sub.waitForMoreMessage {
				time.Sleep(1 * time.Second)
				return fmt.Errorf("no broker partition assignments")
			} else {
				return nil
			}
		}
		// treat the first broker as the topic leader
		// connect to the leader broker

		// subscribe to the topic
		if err := sub.doProcess(); err != nil 
    
func (sub *TopicSubscriber) Subscribe() error {
	index := -1
	util.RetryUntil("subscribe", func() error {
		index++
		index = index % len(sub.bootstrapBrokers)
		// ask balancer for brokers of the topic
		if err := sub.doLookup(sub.bootstrapBrokers[index]); err != nil {
			return fmt.Errorf("lookup topic %s/%s: %v", sub.ContentConfig.Namespace, sub.ContentConfig.Topic, err)
		}
		if len(sub.brokerPartitionAssignments) == 0 {
			if sub.waitForMoreMessage {
				time.Sleep(1 * time.Second)
				return fmt.Errorf("no broker partition assignments")
			} else {
				return nil
			}
		}
		// treat the first broker as the topic leader
		// connect to the leader broker

		// subscribe to the topic
		if err := sub.doProcess(); err != nil {
			return fmt.Errorf("subscribe topic %s/%s: %v", sub.ContentConfig.Namespace, sub.ContentConfig.Topic, err)
		}
		return nil
	}, func(err error) bool {
		if err == io.EOF {
			log.Printf("subscriber %s/%s: %v", sub.ContentConfig.Namespace, sub.ContentConfig.Topic, err)
			sub.waitForMoreMessage = false
			return false
		}
		return true
	})
	return nil
}