Shape-matching in `wrap_address()` doesn't survive 4 backends and
the plans were papering over it: TIPC's natural unwrapped form is
a `(str, int)`, indistinguishable from `TCPAddress`, and iroh's
is a `(str, str)`, which the *existing* UDS case
(`case (_, filename) if type(filename) is str`) already swallows.
So the contract doc (§1.1) now carries the conclusion as a
**recommended prerequisite for all three backends**: make the
unwrapped form carry an explicit proto-key spelled with the
`multiaddr` protocol name — `('tcp', host, port)`,
`('unix', path)`, `('tipc', stype, inst, scope)`. `wrap_address()`
then collapses from an order-sensitive `match` to
`_address_types[addr[0]]` and the whole collision class stops
existing, while the on-wire form finally agrees w/
`mk_maddr()`/`parse_maddr()` instead of being an independent
invention.
Two consequences spelled out: it's a wire-format change
(`SpawnSpec`, `_root_mailbox`, `_registry_addrs`) + every fixture
+ downstream config, so it wants its own migration commit landed
*before* any new backend; and it's the moment to stop handing raw
tuples to users at all — `Address` becomes the public currency
and `UnwrappedAddress` an internal serialization detail, the same
discipline `ipaddress` uses (you pass `IPv4Address`, never a
4-tuple).
Plan 01 §2.2 is rewritten to match and to explicitly **retract**
its own earlier `('tipc:<stype>:<scope>', instance)` self-tagging
prefix hack — it keeps `wrap_address()` order-sensitive and does
nothing for the iroh/UDS collision, so the doc says don't
resurrect it. Registration checklist item 4 likewise becomes "do
the migration first, then this is a one-line `_address_types`
entry".
Also seeds a `/tipc` multiaddr-spec submission as a follow-up,
mirroring the `wg` track (multiformats/py-multiaddr#107/#108 + gh
(this patch was generated in some part by `claude-code` using `claude-opus-5` (`anthropic`))
Plan doc for gh #378, the cheapest new backend we can add: it's
stdlib-only (CPython ships `AF_TIPC` + 23 `TIPC_*` consts) and
per the contract doc `trio`'s stream/listener wrappers don't care
about the addr family, so `MsgpackTransport` framing and
`trio.serve_listeners()` are reused verbatim.
Deats,
- `TIPCAddress` as a *service name* `(type, instance)` w/ scope
as the `.bindspace`; `bind()` publishes the singleton
name-range, peers `connect()` by name and the kernel resolves
+ load-balances. I.e. registration/lookup for free, no
registrar in the loop.
- the self-tagging `('tipc:<stype>:<scope>', instance)` unwrapped
form + why it must be match-ordered before `TCPAddress`'s.
- `get_random()` via a blake2b digest of the actor id (there's no
`port=0` analogue) and the silent-crosstalk risk that follows:
TIPC *allows* dup binders and round-robins, so a collision
doesn't `EADDRINUSE`, it cross-talks.
- an `Address.rebind_from_sockname` ClassVar to opt out of
`Endpoint.start_listener()`'s `getsockname()` reconcile, which
for TIPC always returns a port-id, never the bound name.
- the `TIPC_TOP_SRV` topology-service subscription as an `@acm`
yielding a chan of typed name-table events — push-based
register/dereg, the real "end game cluster proto" bit.
- commit sequencing, hard capability gating (`modprobe tipc`;
bare `AF_TIPC` is `EAFNOSUPPORT` on a stock box), CI matrix
notes, risks + follow-up seeds.
(this patch was generated in some part by `claude-code` using `claude-opus-5` (`anthropic`))
Gud Boi