Example #1
0
// CopyShards will create the shards in the destination topo
func CopyShards(fromTS, toTS topo.Server, deleteKeyspaceShards bool) {
	keyspaces, err := fromTS.GetKeyspaces()
	if err != nil {
		log.Fatalf("fromTS.GetKeyspaces: %v", err)
	}

	wg := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	for _, keyspace := range keyspaces {
		wg.Add(1)
		go func(keyspace string) {
			defer wg.Done()
			shards, err := fromTS.GetShardNames(keyspace)
			if err != nil {
				rec.RecordError(fmt.Errorf("GetShardNames(%v): %v", keyspace, err))
				return
			}

			if deleteKeyspaceShards {
				if err := toTS.DeleteKeyspaceShards(keyspace); err != nil {
					rec.RecordError(fmt.Errorf("DeleteKeyspaceShards(%v): %v", keyspace, err))
					return
				}
			}

			for _, shard := range shards {
				wg.Add(1)
				go func(keyspace, shard string) {
					defer wg.Done()
					if err := topo.CreateShard(toTS, keyspace, shard); err != nil {
						if err == topo.ErrNodeExists {
							log.Warningf("shard %v/%v already exists", keyspace, shard)
						} else {
							rec.RecordError(fmt.Errorf("CreateShard(%v, %v): %v", keyspace, shard, err))
							return
						}
					}

					si, err := fromTS.GetShard(keyspace, shard)
					if err != nil {
						rec.RecordError(fmt.Errorf("GetShard(%v, %v): %v", keyspace, shard, err))
						return
					}

					toSi, err := toTS.GetShard(keyspace, shard)
					if err != nil {
						rec.RecordError(fmt.Errorf("toTS.GetShard(%v, %v): %v", keyspace, shard, err))
						return
					}

					if _, err := toTS.UpdateShard(si, toSi.Version()); err != nil {
						rec.RecordError(fmt.Errorf("UpdateShard(%v, %v): %v", keyspace, shard, err))
					}
				}(keyspace, shard)
			}
		}(keyspace)
	}
	wg.Wait()
	if rec.HasErrors() {
		log.Fatalf("copyShards failed: %v", rec.Error())
	}
}