So i need to either adjust the tests or figure out if/why this is needed
to avoid the crashing in `pikerd` i found when killin the chart during
a long backfill with `binance` backend..
Just like in the BRE case (for UDS) it seems when a peer closes the
(UDS?) socket `trio` instead raises a `ClosedResourceError` which we now
catch and re-raise as a `TransportClosed`. This again results in
`tpt.send()` calls from the rpc-runtime **not** raising when it's known
that the IPC channel is disconnected.
Shift around comments and expressions for better reading, assign
`tpt_closed` for easier introspection from REPL during debug oh and fix
the `MsgpackTransport.pformat()` to render '|_peers: 1' .. XD
Such that re-wrapping/raising from a low-level `trio` resource error is
simpler and includes the `.src_exc` in the `__repr__()` and
`.message/.args` rendered at higher layers (like from `Channel` and
`._rpc` machinery).
Impl deats,
- mainly leverages packing in a new cls-method `.repr_src_exc() -> str:`
repr of the underlying error before an optional `body: str` all as
handled by the previously augmented `.pformat()`'s delegation to
`pformat_exc()`.
- change `.src_exc` to be a property around a renamed `._src_exc`.
But wait, why?
- use it inside `MsgpackTransport.send()` to rewrap any
`trio.BrokenResourceError`s so we always see the underlying
`trio`-src-exc just like in the `.recv()._iter_packets()` handlers.
Primarily moving the `Actor._serve_forever()`-task-as-method and
supporting actor-instance attributes to a new `.ipo._server` sub-mod
which now encapsulates,
- the coupling various `trio.Nursery`s (and their independent lifetime mgmt)
to different `trio.serve_listener()`s tasks and `SocketStream`
handler scopes.
- `Address` and `SocketListener` mgmt and tracking through the idea of
an "IPC endpoint": each "bound-and-active instance" of a served-listener
for some (varied transport protocol's socket) address.
- start and shutdown of the entire server's lifetime via an `@acm`.
- delegation of starting/stopping tpt-protocol-specific `trio.abc.Listener`s
to the corresponding `.ipc._<proto_key>` sub-module (newly defined
mod-top-level instead of `Address` method) `start/close_listener()`
funcs.
Impl details of the `.ipc._server` sub-sys,
- add new `IPCServer`, allocated with `open_ipc_server()`, and which
encapsulates starting multiple-transport-proto-`trio.abc.Listener`s
from an input set of `._addr.Address`s using,
|_`IPCServer.listen_on()` which internally spawns tasks that delegate to a new
`_serve_ipc_eps()`, a rework of what was (effectively)
`Actor._serve_forever()` and which now,
* allocates a new `IPCEndpoint`-struct (see below) for each
address-listener pair alongside the specified
listener-serving/stream-handling `trio.Nursery`s provided by the
caller.
* starts and stops each transport (socket's) listener by calling
`IPCEndpoint.start/close_listener()` which in turn delegates to
the underlying `inspect.getmodule(IPCEndpoint.addr)` backend tpt
module's equivalent impl.
* tracks all created endpoints in a `._endpoints: list[IPCEndpoint]`
which is further exposed through public properties for
introspection of served transport-protocols and their addresses.
|_`IPCServer._[parent/stream_handler]_tn: Nursery`s which are either
allocated (in which case, as the same instance) or provided by the
caller of `open_ipc_server()` such that the same nursery-cancel-scope
controls offered by `trio.serve_listeners(handler_nursery=)` are
offered where the `._parent_tn` is used to spawn `_serve_ipc_eps()`
tasks, and `._stream_handler_tn` is passed verbatim as `handler_nursery`.
- a new `IPCEndpoint`-struct (as mentioned) which wraps each
transport-proto's address + listener + allocated-supervising-nursery
to encapsulate the "lifetime of a server IPC endpoint" such that
eventually we can track and managed per-protocol/address/`.listen_on()`-call
scoped starts/stops/restarts for the purposes of filtering/banning
peer traffic.
|_ also included is an unused `.peer_tpts` table which we can
hopefully use to replace `Actor._peers` in a `Channel`-tracking
transport-proto-aware way!
Surrounding changes to `.ipc.*` primitives to match,
- make `[TCP|UDS]Address` types `msgspec.Struct(frozen=True)` and thus
drop any-and-all `addr._host =` style mutation throughout.
|_ as such also drop their `.__init__()` and `.__eq__()` meths.
|_ UDS tweaks to field names and thus `.__repr__()`.
- move `[TCP|UDS]Address.[start/close]_listener()` meths to be mod-level
equiv `start|close_listener()` funcs.
- just hard code the `.ipc._types._key_to_transport/._addr_to_transport`
table entries instead of all the prior fancy dynamic class property
reading stuff (remember, "explicit is better then implicit").
Modified in `._runtime.Actor` internals,
- drop the `._serve_forever()` and `.cancel_server()`, methods and
`._server_down` waiting logic from `.cancel_soon()`
- add `.[_]ipc_server` which is opened just after the `._service_n` and
delegate to it for any equivalent publicly exposed instance
attributes/properties.
That is moving from `._addr`,
- `TCPAddress` to `.ipc._tcp`
- `UDSAddress` to `.ipc._uds`
Obviously this requires adjusting a buncha stuff in `._addr` to avoid
import cycles (the original reason the module was not also included in
the new `.ipc` subpkg) including,
- avoiding "unnecessary" imports of `[Unwrapped]Address` in various modules.
* since `Address` is a protocol and the main point is that it **does
not need to be inherited** per
(https://typing.python.org/en/latest/spec/protocol.html#terminology)
thus I removed the need for it in both transport submods.
* and `UnwrappedAddress` is a type alias for tuples.. so we don't
really always need to be importing it since it also kinda obfuscates
what the underlying pairs are.
- not exporting everything in submods at the `.ipc` top level and
importing from specific submods by default.
- only importing various types under a `if typing.TYPE_CHECKING:` guard
as needed.
By borrowing from the implementation of `RemoteActorError.pformat()`
which is now factored into a new `.devx.pformat_exc()` and re-used for
both error types while maintaining the same func-sig. Obviously delegate
`RemoteActorError.pformat()` to the new helper accordingly and keeping
the prior `body` generation from `.devx.pformat_boxed_tb()` as before.
The new helper allows for,
- passing any of a `header|message|body: str` which are all combined in
that order in the final output.
- getting the `exc.message` as the default `message` part.
- generating an objecty-looking "type-name" header to be rendered by
default when `header` is not overridden.
- "first-line-of `message`" processing which we split-off and then
re-inject as a `f'<{type(exc).__name__}( {first} )>'` top line header.
- an optional `tail: str = '>'` to "close the object"-look only added
when `with_type_header: bool = True`.
Adjustments to `TransportClosed` around this include,
- replacing the init `cause` arg for a `src_exc` which is now always
assigned to a same named instance var.
- displaying that new `.src_exc` in the `body: str` arg to the
`.devx.pformat.pformat_exc()` call so you can always see the
underlying (normally `trio`) source error.
- just make it inherit from `Exception` not `trio.BrokenResourceError`
to avoid handlers catching `TransportClosed` as the former
particularly in testing when we want to sometimes to distinguish them.
Much like we already do in the `._iter_packets()` async-generator which
delivers to `.recv()` and `async for`, handle the `''[Errno 32] Broken
pipe'` case that can show up with unix-domain-socket usage.
Seems like the cause is due to how fast the socket can be torn down
during a registry addr channel ping where,
- the sending side can break the connection faster then the pong side
can prep its handshake msg,
- the pong side tries to send it's handshake pkt via
`.SocketStream.send_all()` after the breakage and then raises
`trio.BrokenResourceError`.
Tyler Goodlet
Guillermo Rodriguez