| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| encoding/binary | Package binary implements simple translation between numbers and byte sequences and encoding and decoding of varints. |
| github.com/golang/protobuf/ptypes/empty | |
| github.com/golang/protobuf/ptypes/struct | |
| github.com/golang/protobuf/ptypes/timestamp | |
| google.golang.org/genproto/googleapis/spanner/v1 | Package spanner aliases all exported identifiers in package "cloud.google.com/go/spanner/apiv1/spannerpb". |
| google.golang.org/grpc | Package grpc implements an RPC system called gRPC. |
| net | Package net provides a portable interface for network I/O, including TCP/IP, UDP, domain name resolution, and Unix domain sockets. |
| time | Package time provides functionality for measuring and displaying time. |