func (this *SaramaPartitioner) Partition(key sarama.Encoder, numPartitions int32) (int32, error) {
keyBytes, err := key.Encode()
if err != nil {
return -1, err
}
return this.partitioner.Partition(keyBytes, numPartitions)
}
// Partition takes the key and partition count and chooses a partition. IntPartitioner should ONLY receive Int32Encoder keys.
// Passing it a Int32Encoder(2) key means it should assign the incoming message partition = 2 (assuming this partition exists, otherwise there's no guarantee which partition will be picked).
func (this *IntPartitioner) Partition(key sarama.Encoder, numPartitions int32) (int32, error) {
if key == nil {
panic("IntPartitioner does not work without keys.")
}
b, err := key.Encode()
if err != nil {
return -1, err
}
buf := bytes.NewBuffer(b)
partition, err := binary.ReadUvarint(buf)
if err != nil {
return -1, err
}
return int32(partition) % numPartitions, nil
}