func (ctx *DataContext) ClientFromKey(key Key) (dvid.ClientID, error) { if key == nil { return 0, fmt.Errorf("Cannot extract DataContext client from nil key") } if key[0] != dataKeyPrefix { return 0, fmt.Errorf("Cannot extract DataContext client from different key type") } start := len(key) - dvid.ClientIDSize - 1 // substract client, and tombstone return dvid.ClientIDFromBytes(key[start : start+dvid.ClientIDSize]), nil }
// KeyToLocalIDs parses a key under a DataContext and returns instance, version and client ids. func DataKeyToLocalIDs(k Key) (dvid.InstanceID, dvid.VersionID, dvid.ClientID, error) { if k[0] != dataKeyPrefix { return 0, 0, 0, fmt.Errorf("Cannot extract local IDs from a non-DataContext key") } instanceID := dvid.InstanceIDFromBytes(k[1 : 1+dvid.InstanceIDSize]) start := len(k) - dvid.VersionIDSize - dvid.ClientIDSize - 1 versionID := dvid.VersionIDFromBytes(k[start : start+dvid.VersionIDSize]) start += dvid.VersionIDSize clientID := dvid.ClientIDFromBytes(k[start : start+dvid.ClientIDSize]) return instanceID, versionID, clientID, nil }
// ClientFromKey returns a clientID from a full key. Any DataContext is sufficient as receiver. func (ctx *DataContext) ClientFromKey(key Key) (dvid.ClientID, error) { if key == nil { return 0, fmt.Errorf("Cannot extract DataContext client from nil key") } if key[0] != dataKeyPrefix { return 0, fmt.Errorf("Cannot extract DataContext client from different key type") } if len(key) < dvid.InstanceIDSize+dvid.VersionIDSize+dvid.ClientIDSize+2 { // TKey must be 0 or larger. return 0, fmt.Errorf("Cannot extract client from DataKey that is only %d bytes", len(key)) } start := len(key) - dvid.ClientIDSize - 1 // substract client, and tombstone return dvid.ClientIDFromBytes(key[start : start+dvid.ClientIDSize]), nil }