v3.1.0

Summary

This release adds full support for embedded (anonymous) structs with an optimized fast path when embedding is not used, aligning struct field promotion and conflict resolution with encoding/json.

Highlights

• Added embedded struct field collection and promotion, including tag-aware precedence and ambiguity handling.
• Preserved a fast path for non-embedded structs; uses path-based access only when embedding is present.
• Added omitempty handling on embedded parents, omitting promoted fields when the parent is zero or nil.
• Added decoding support for embedded pointer structs with allocation when needed.

Behavior Changes

• Embedded struct fields are now promoted by default (unless the embedded field is tagged).
• Ambiguous field names from multiple embedded structs are omitted (matching encoding/json behavior).
• omitempty on an embedded parent can suppress all promoted fields when the parent is zero or nil.

Tests

• Added comprehensive tests for embedded structs, tag behavior, shadowing, ambiguity, pointer embedding, and omitempty.

Full Changelog: https://github.com/shamaton/msgpack/commits/v3.1.0

v3.0.0

Breaking Changes

• Module path changed to github.com/shamaton/msgpack/v3 (update imports and go get)
• Default time.Time decoding is now UTC (use msgpack.SetDecodedTimeAsLocal() to keep v2 behavior)

Upgrade Guide

1. Update module path: go get -u github.com/shamaton/msgpack/v3
2. Replace imports from github.com/shamaton/msgpack/v2 to github.com/shamaton/msgpack/v3
3. If you rely on local time decoding, call: msgpack.SetDecodedTimeAsLocal()

Compatibility

• Go version updated to go 1.23

Documentation

• README updated with v3 install and v2 upgrade guidance

Full Changelog: v2.4.0...v3.0.0

v2.4.0

Highlights

• New global switches to control the timezone used when decoding MessagePack Timestamp into Go’s time.Time.
• No breaking changes in v2.4.0. The default behavior remains Local.
• Heads-up for v3: default decoded time.Time will change to UTC (instant unchanged).

Added

• msgpack.SetDecodedTimeAsUTC() — forces decoded time.Time to use UTC.
• msgpack.SetDecodedTimeAsLocal() — forces decoded time.Time to use Local (mirrors current default in v2.x).

These functions allow you to preview and standardize your runtime behavior before upgrading to v3.

Why this matters

MessagePack’s Timestamp represents an instant (epoch seconds + nanoseconds) and does not carry timezone info. Historically, decoding to Local could lead to environment-dependent differences across hosts. Many distributed systems and APIs prefer UTC for predictability.

Usage

// Opt in to UTC decoding on v2.x (recommended for distributed systems/APIs)
msgpack.SetDecodedTimeAsUTC()

// Restore/keep Local decoding explicitly
msgpack.SetDecodedTimeAsLocal()

Note: v2.4.0 still defaults to Local unless you call SetDecodedTimeAsUTC().

What’s next (v3 heads-up)

In v3.0.0, the default decoded time.Time location will change from Local to UTC.
The encoded/decoded instant is unchanged; only time.Time.Location() differs.
If you rely on local display, you’ll be able to call msgpack.SetDecodedTimeAsLocal() to keep the old behavior.

Migration tips

• If your UI expects local time, call msgpack.SetDecodedTimeAsLocal() at startup.
• For logs/APIs/DBs, consider standardizing on UTC now via msgpack.SetDecodedTimeAsUTC() to smooth the v3 upgrade.
• Tests that assert string forms of time.Time may need to normalize to UTC or set the desired location explicitly.

Links

• Issue: #51
• PR: #52

Full Changelog: v2.3.1...v2.4.0

v2.3.1

What's Changed

• Fix calcuration size of Ext format by @shamaton in #48

Full Changelog: v2.3.0...v2.3.1

v2.3.0

What's Changed

• support for omitempty in tag by @shamaton in #47

Full Changelog: v2.2.3...v2.3.0

v2.2.3

What's Changed

• Fix UnmarshalRead binary slice case by @shamaton in #45

Full Changelog: v2.2.2...v2.2.3

v2.2.2

What's Changed

• add 1.23 and remove 1.20 as test targets by @shamaton in #40
• Update stream ext encoder interface by @shamaton in #41

Full Changelog: v2.2.1...v2.2.2

v2.2.1

What's Changed

• Add internal tests and fix some bugs by @shamaton in #39

fixed in 2226b13 , fa57eea , 7155d37

Full Changelog: v2.2.0...v2.2.1

v2.2.0

What's Changed

• Update test workflow by @shamaton in #36
• Add streaming function by @shamaton in #38

Full Changelog: v2.1.1...v2.2.0

v2.1.1

Merge pull request #32 from shamaton/case_crash

Return error when strange data is received