Documentation
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Overview ¶
Package msgpack decodes a MessagePack-encoded value to a structured tree — the compact binary serialization (https://msgpack.org) used by Redis internals, msgpack-RPC, many web/API backends, mobile sync protocols, and game-server traffic. It is the binary-serialization sibling of cbor_decode: an operator pastes the hex of a captured msgpack blob (from a packet dump, a cache value, a stored token) and gets the decoded structure without writing a throwaway script. Pure offline transform; no network or device.
Wrap-vs-native judgement ¶
Native. MessagePack is a fully public, byte-oriented format (github.com/msgpack/msgpack spec.md) — a one-byte type tag selecting a fixed family (fixint / fixstr / fixarray / fixmap, nil/bool, bin, ext, the big-endian uint/int/float widths, and the str/array/map length-prefixed forms). It is a recursive-descent walk over a byte cursor; there is nothing to wrap, and adding github.com/vmihailenco/msgpack as a runtime dependency to decode untrusted bytes is unwarranted. Consistent with internal/cbordecode and internal/protobufdecode owning their parse in-tree.
Verifiable / no confidently-wrong output ¶
Strongest verification class — every format family is gated byte-for-byte against vectors produced by the reference `msgpack` Python library (nil/bool, fixint / negative fixint, uint8..uint64, int8..int64, float32/float64, fixstr / str8, bin8, fixarray, fixmap, fixext4, and a nested map/array). A truncated or malformed blob is rejected with an error (never a partial/guessed decode), the reserved 0xc1 tag is rejected, and any trailing bytes after the top-level value are surfaced as trailing_bytes_hex rather than ignored.
Covered / deferred ¶
Covered: all MessagePack core types, plus the Timestamp extension (ext type -1) decoded to RFC 3339 across all three wire layouts — 32-bit (uint32 seconds), 64-bit (30-bit nanoseconds + 34-bit seconds) and 96-bit (uint32 nanoseconds + signed int64 seconds, so pre-epoch times decode correctly). A non-standard Timestamp length or an out-of-range nanoseconds field is left raw with a note rather than decoded into a confidently-wrong time. Other extension types are surfaced as raw (extension type + data hex). Invalid-UTF-8 str payloads are surfaced as hex with a note instead of an invalid string.
Index ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Result ¶
type Result struct {
Value *Value `json:"value"`
TotalBytes int `json:"total_bytes"`
TrailingHex string `json:"trailing_bytes_hex,omitempty"`
TrailingCount int `json:"trailing_bytes,omitempty"`
}
Result is the decoded top-level value plus framing metadata.
func Decode ¶
Decode parses the hex of a MessagePack blob (separators and an optional 0x prefix tolerated) into a single top-level value.
func DecodeBytes ¶
DecodeBytes parses a MessagePack blob from raw bytes.
type Value ¶
type Value struct {
Type string `json:"type"`
Format string `json:"format"`
Bool *bool `json:"bool,omitempty"`
Int *int64 `json:"int,omitempty"`
Uint *uint64 `json:"uint,omitempty"`
Float *float64 `json:"float,omitempty"`
Str *string `json:"str,omitempty"`
// BytesHex carries a bin payload, or a str payload that is not valid UTF-8.
BytesHex string `json:"bytes_hex,omitempty"`
Note string `json:"note,omitempty"`
Array []*Value `json:"array,omitempty"`
Map []*MapEntry `json:"map,omitempty"`
// Ext fields (msgpack extension types).
ExtType *int8 `json:"ext_type,omitempty"`
ExtData string `json:"ext_data_hex,omitempty"`
// Timestamp fields, set when an ext type -1 carries a well-formed
// MessagePack Timestamp (Type becomes "timestamp").
Timestamp string `json:"timestamp,omitempty"` // RFC 3339 (UTC)
TimestampUnixSec *int64 `json:"timestamp_unix_sec,omitempty"`
TimestampNanos *uint32 `json:"timestamp_nanos,omitempty"`
}
Value is one decoded MessagePack value.
Source Files