go-libp2p v0.31

[marten-seemann]

🗺 What's left for release

Planned release date: Aug 28th (Kubo v0.23 cutoff is Aug 31st, see ipfs/kubo#10014)

Experimental libp2p+HTTP:

• feat: Implement HTTP spec #2438

Misc:

• swarm.DialError should wrap DialError.DialErrors #2436
• update quic-go to v0.38.1 #2506
• feat: add ErrPeerIDMismatch error type to replace ad-hoc errors #2451
• swarm: return errors on filtered addresses when dialing #2461
• Use CancelWithCause in swarm.dialPeer for better metrics reporting #2321

QUIC:

• update to quic-go v0.38.x
• Better error message when trying to dial /quic peer #2515

🔦 Highlights

< top highlights for this release notes >

libp2p+HTTP

We're introducing a new experimental API in go-libp2p, enabling developers to utilize libp2p with the well-known semantics of HTTP. This isn't a special flavor of HTTP; it's standard HTTP, but enhanced with libp2p. Developers can now benefit from HTTP intermediaries such as CDN caching and layer 7 load balancing. This allows developers to create HTTP applications that operate over NATs and seamlessly tap into libp2p's diverse transport options to boost connectivity. In addition, the HTTP transport now joins the roster of supported transports in libp2p.

The new API is under libp2phttp.Host in the "github.com/libp2p/go-libp2p/p2p/http" package. This is like the stream transport host (host.Host in "github.com/libp2p/go-libp2p/core/host"), but exposes HTTP request/response rather than a stream API. Refer to the godoc for details on the API and examples.

QUIC Generic Segmentation Offload

This release updates quic-go to v0.38.x, which enables GSO (Generic Segmentation Offload) in the send path, drastically increasing the packet send rate. Without GSO, quic-go had to use a single sendmsg syscall for every UDP datagram sent. GSO allows us to pass one giant (up to 64k) datagram to the sendmsg syscall, and have the kernel chop it into MTU sized (~1300 bytes) datagrams before sending them out on the wire. For more details on syscall optimizations, CloudFlare published an excellent blog post about this a while ago. GSO is currently only available on Linux (and with kernels >4.18).

Changelog

< changelog generated by scripts/mkreleaselog >

✅ Release Checklist

• Stage 0 - Finishing Touches
  • Go through relevant libp2p repos looking for unreleased changes that should make it into the release. If you find any, cut releases.
  • Run go get -u ./... to see if there are any out-of-date deps that look important. If there are, bubble them. Try to avoid directly updating indirect deps in go-libp2p's go.mod when possible.
• Stage 1 - Release
  • Publish the release through the GitHub UI, adding the release notes. Some users rely on this to receive notifications of new releases.
  • Announce the release on the discuss.libp2p.io.
• Stage 2 - Update Upstream
  • Update the examples to the final release chore: update examples to v0.31 #2544
  • Update the upstream dependencies to the final release and create PRs.
    • filecoin-project/lotus
    • go-libp2p-kad-dht
    • go-libp2p-pubsub (In case of breaking changes.)
    • ipfs/kubo chore: update boxo, go-libp2p, and internalize mplex ipfs/kubo#10095
  • Add new release to interop tester in test-plans chore(multidim-interop): add go v0.31 test-plans#289
• Make required changes to the release process.

[master255]

Great Job!