Enable webtransport endpoint

[dirkmc]

See filecoin-project/lotus#10122

We will need to think through performance and privacy applications, but seems likely to enable some useful use cases.

[aschmahmann]

This seems like it'd be very useful to allow peers in browser environments to access the libp2p transport protocols offered by Boost. Some information about WebTransport and libp2p.

While WSS could also be enabled if desired, WebTransport has fewer round-trips and does not require a certificate-authority approved domain name to work which makes deployment easier.

Overall enabling the endpoint should be very straightforward once you update go-libp2p. You just have to enable a listener address and the WebTransport transport and you're good to go 🚀.

---

I was asked about about the comparison of adding this feature vs adding support for the IPFS trustless-gateway-spec (although I don't see why not both 😄).

Assuming CA domains aren't an issue (they might be for people) then basically the benefits you have are related to either the data transfer protocols or current ecosystem support.

• Content Routing
  • There are currently no HTTP data transfer protocols specifiable in IPNI. You can do it in a few kind of hacky ways (Will and I have done demos like this), but IPNI is a little too tied to peerIDs at the moment
• Data Transfer
  • What the trustless gateways support is currently pretty barebones. Hopefully that'll evolve as we work an Rhea (some ongoing work https://www.notion.so/pl-strflt/Rhea-workstream-tracker-d21511c00b79449b8ab941cbe493aa2f?p=97cc90e74df44404a0f9aa29d7291a5f&pm=s and https://www.notion.so/pl-strflt/HTTP-Gateway-Requests-for-Graphs-as-CARs-001d2a9f5a35418bb0fb7d9d182d24ec)
  • However, even then we're probably not going to arrive at a place where we can describe non-UnixFS data reliably well which means sometimes relying on block protocols. I wouldn't be surprised if Bitswap ended up being more efficient than format=raw given it can group blocks, although could go either way I guess depending on how things are configured for each 🙂
  • While work is happening on this, we don't have any multi-protocol download libraries so while incorporating both Bitswap-over-WebTransport and format=raw HTTP requests should be very doable it doesn't exist yet.