package balancer import ( "errors" "github.com/seaweedfs/seaweedfs/weed/pb/mq_pb" ) var ( ErrNoBroker = errors.New("no broker") ) func (b *Balancer) LookupOrAllocateTopicPartitions(topic *mq_pb.Topic, publish bool, partitionCount int32) (assignments []*mq_pb.BrokerPartitionAssignment, err error) { // find existing topic partition assignments for brokerStatsItem := range b.Brokers.IterBuffered() { broker, brokerStats := brokerStatsItem.Key, brokerStatsItem.Val for topicPartitionStatsItem := range brokerStats.Stats.IterBuffered() { topicPartitionStat := topicPartitionStatsItem.Val if topicPartitionStat.TopicPartition.Namespace == topic.Namespace && topicPartitionStat.TopicPartition.Topic == topic.Name { assignment := &mq_pb.BrokerPartitionAssignment{ Partition: &mq_pb.Partition{ RingSize: MaxPartitionCount, RangeStart: topicPartitionStat.RangeStart, RangeStop: topicPartitionStat.RangeStop, }, } if topicPartitionStat.IsLeader { assignment.LeaderBroker = broker } else { assignment.FollowerBrokers = append(assignment.FollowerBrokers, broker) } assignments = append(assignments, assignment) } } } if len(assignments) > 0 { return assignments, nil } // find the topic partitions on the filer // if the topic is not found // if the request is_for_publish // create the topic // if the request is_for_subscribe // return error not found // t := topic.FromPbTopic(request.Topic) if b.Brokers.IsEmpty() { return nil, ErrNoBroker } return allocateTopicPartitions(b.Brokers, partitionCount), nil }