| bytes | Package bytes implements functions for the manipulation of byte slices. |
| crypto/hmac | Package hmac implements the Keyed-Hash Message Authentication Code (HMAC) as defined in U.S. |
| crypto/sha1 | Package sha1 implements the SHA1 hash algorithm as defined in RFC 3174. |
| crypto/sha256 | Package sha256 implements the SHA224 and SHA256 hash algorithms as defined in FIPS 180-4. |
| encoding/hex | Package hex implements hexadecimal encoding and decoding. |
| encoding/json | Package json implements encoding and decoding of JSON objects as defined in RFC 4627. |
| 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/cloud/compute/metadata | Package metadata provides access to Google Compute Engine (GCE) metadata and API service accounts. |
| hash | Package hash provides interfaces for hash functions. |
| io | Package io provides basic interfaces to I/O primitives. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| log | Package log implements a simple logging package. |
| net/http | Package http provides HTTP client and server implementations. |
| net/url | Package url parses URLs and implements query escaping. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| time | Package time provides functionality for measuring and displaying time. |