| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| encoding/base64 | Package base64 implements base64 encoding as specified by RFC 4648. |
| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| google.golang.org/grpc/attributes | Package attributes defines a generic key/value store used in various gRPC components. |
| google.golang.org/grpc/credentials | Package credentials implements various credentials supported by gRPC library, which encapsulate all the state needed by a client to authenticate with a server and make various assertions, e.g., about the client's identity, role, or whether it is authorized to make a particular call. |
| google.golang.org/grpc/experimental/stats | Package stats contains experimental metrics/stats API's. |
| google.golang.org/grpc/internal | Package internal contains gRPC-internal code, to avoid polluting the godoc of the top-level grpc package. |
| google.golang.org/grpc/serviceconfig | Package serviceconfig defines types and methods for operating on gRPC service configs. |
| net | Package net provides a portable interface for network I/O, including TCP/IP, UDP, domain name resolution, and Unix domain sockets. |
| net/url | Package url parses URLs and implements query escaping. |
| sort | Package sort provides primitives for sorting slices and user-defined collections. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |