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.
Throughout `_context` and `_spawn` where it causes no big disruption.
Still lots to work out for things like how to pass `--uid
<tuple-as-str>` to spawned subactors and whether we want a diff name for
the minimum `tuple` required to distinguish a subactor pre-process-ID
allocation by the OS.
Such that any `Return` is always capture for each ctx instance and set
in `._deliver_msg()` normally; ensures we can at least introspect for it
when missing (like in a recently discovered stream teardown race bug).
Yes this augments the already existing `._result` which is dedicated for
the `._outcome_msg.pld` in the non-error case; we might want to see if
there's a nicer way to directly proxy ref to that without getting the
pre-pld-decoded `Raw` form with `msgspec`?
Also use the new `ctx._pld_rx.recv_msg()` and drop assigning
`pld_rx._ctx`.
Since it'll likely need a bit of detailing to get the test suite running
identically with strict egs (exception groups), i've opted to just flip
the switch on a few core nursery scopes for now until as such a time
i can focus enough to port the matching internals.. Xp
As per a WIP scribbled out TODO in `._entry.nest_from_op()`, change
a bunch of "supervisor/lifetime mgmt ops" related log messages to
contain some supervisor-annotation "headers" in an effort to give
a terser "visual indication" of how some execution/scope/storage
primitive entity (like an actor/task/ctx/connection) is being operated
on (like, opening/started/closed/cancelled/erroring) from a "supervisor
action" POV.
Also tweak a bunch more emissions to lower levels to reduce noise around
normal inter-actor operations like process and IPC ctx supervision.
Not sure how I forgot this but, obviously it's correct context-var
semantics to revert the current IPC `Context` (set in the latest
`.open_context()` block) such that any prior instance is reset..
This ensures the sanity `assert`s pass inside
`.msg._ops.maybe_limit_plds()` and just in general ensures for any task
that the last opened `Context` is the one returned from
`current_ipc_ctx()`.
Might as well add a public maybe-getter for use on the "parent" side
since it can be handy to check out-of-band cancellation conditions (like
from `Portal.cancel_actor()`).
Buncha bitty tweaks for more easily debugging cancel conditions:
- add a `@.cancel_called.setter` for hooking into `.cancel_called = True`
being set in hard to decipher "who cancelled us" scenarios.
- use a new `self_ctxc: bool` var in `.cancel()` to capture the output
state from `._is_self_cancelled(remote_error)` at call time so it can
be compared against the measured value at crash-time (when REPL-ing it
can often have already changed due to runtime teardown sequencing vs.
the crash handler hook entry).
- proxy `hide_tb` to `.drain_to_final_msg()` from `.wait_for_result()`.
- use `remote_error.sender` attr directly instead of through
`RAE.msgdata: dict` lookup.
- change var name `our_uid` -> `peer_uid`; it's not "ours"..
Other various docs/comment updates:
- extend the main class doc to include some other name ideas.
- change over all remaining `.result()` refs to `.wait_for_result()`.
- doc more details on how we want `.outcome` to eventually signature.
Name them `_mk_send_mte()`/`_mk_recv_mte()` and change the runtime to
call each appropriately depending on location/usage.
Also add some dynamic call-frame "unhide" blocks such that when we
expect raised MTE from the aboves calls but we get a different
unexpected error from the runtime, we ensure the call stack downward is
shown in tbs/pdb.
|_ ideally in the longer run we come up with a fancier dynamic sys for
this, prolly something in `.devx._frame_stack`?
Instead of the WIP/prototyped `Portal.open_context()` offering
a `pld_spec` input arg, this changes to a proper decorator API for
specifying the "payload spec" on `@context` endpoints.
The impl change details actually cover 2-birds:
- monkey patch decorated functions with a new
`._tractor_context_meta: dict[str, Any]` and insert any provided input
`@context` kwargs: `_pld_spec`, `enc_hook`, `enc_hook`.
- use `inspect.get_annotations()` to scan for a `func` arg
type-annotated with `tractor.Context` and use the name of that arg as
the RPC task-side injected `Context`, thus injecting the needed arg
by type instead of by name (a longstanding TODO); raise a type-error
when not found.
- pull the `pld_spec` from the `._tractor_context_meta` attr both in the
`.open_context()` parent-side and child-side `._invoke()`-cation of
the RPC task and use the `msg._ops.maybe_limit_plds()` API to apply it
internally in the runtime for each case.
Longer run we don't want `tractor` app devs having to call
`msg._ops.limit_plds()` from every child endpoint.. so this starts
a list of decorator API ideas and obviously ties in with an ideal final
API design that will come with py3.13 and typed funcs. Obviously this
is directly fueled by,
- https://github.com/goodboy/tractor/issues/365
Other,
- type with direct `trio.lowlevel.Task` import.
- use `log.exception()` to show tbs for all error-terminations in
`.open_context()` (for now) and always explicitly mention the `.side`.
Exactly like how it's organized for `Portal.open_context()`, put the
main streaming API `@acm` with the `MsgStream` code and bind the method
to the new module func.
Other,
- rename `Context.result()` -> `.wait_for_result()` to better match the
blocking semantics and rebind `.result()` as deprecated.
- add doc-str for `Context.maybe_raise()`.
That is as a control to `Context._maybe_raise_remote_err()` such that
if set to anything other then the default (`False` value), we do
`raise remote_error from from_src_exc` such that caller can choose to
suppress or override the `.__cause__` tb.
Also tidy up and old masked TODO regarding calling `.maybe_raise()`
after the caller exits from the `yield` in `.open_context()`..
More specifically, if `.open_context()` is cancelled when awaiting the
first `Context.started()` during the child task sync phase, check to see
if it was due to `._scope.cancel_called` and raise any remote error via
`.maybe_raise()` instead the `trio.Cancelled` like in every other
remote-error handling case. Ensure we set `._scope[_nursery]` only after
the `Started` has arrived and audited.
Filling out the helper `validate_payload_msg()` staged in a prior commit
and adjusting all imports to match.
Also add a `raise_mte: bool` flag for potential usage where the caller
wants to handle the MTE instance themselves.
In the sense that we handle it as a special case that exposed
through to `RxPld.dec_msg()` with a new `is_started_send_side: bool`.
(Non-ideal) `Context.started()` impl deats:
- only do send-side pld-spec validation when a new `validate_pld_spec`
is set (by default it's not).
- call `self.pld_rx.dec_msg(is_started_send_side=True)` to validate the
payload field from the just codec-ed `Started` msg's `msg_bytes` by
passing the `roundtripped` msg (with it's `.pld: Raw`) directly.
- add a `hide_tb: bool` param and proxy it to the `.dec_msg()` call.
(Non-ideal) `PldRx.dec_msg()` impl deats:
- for now we're packing the MTE inside an `Error` via a manual call to
`pack_error()` and then setting that as the `msg` passed to
`_raise_from_unexpected_msg()` (though really we should just raise
inline?).
- manually set the `MsgTypeError._ipc_msg` to the above..
Other,
- more comprehensive `Context` type doc string.
- various `hide_tb: bool` kwarg additions through `._ops.PldRx` meths.
- proto a `.msg._ops.validate_payload_msg()` helper planned to get the
logic from this version of `.started()`'s send-side validation so as
to be useful more generally elsewhere.. (like for raising back
`Return` values on the child side?).
Warning: this commit may have been made out of order from required
changes to `._exceptions` which will come in a follow up!
Since the state mgmt becomes quite messy with multiple sub-tasks inside
an IPC ctx, AND bc generally speaking the payload-type-spec should map
1-to-1 with the `Context`, it doesn't make a lot of sense to be using
`ContextVar`s to modify the `Context.pld_rx: PldRx` instance.
Instead, always allocate a full instance inside `mk_context()` with the
default `.pld_rx: PldRx` set to use the `msg._ops._def_any_pldec: MsgDec`
In support, simplify the `.msg._ops` impl and APIs:
- drop `_ctxvar_PldRx`, `_def_pld_rx` and `current_pldrx()`.
- rename `PldRx._pldec` -> `._pld_dec`.
- rename the unused `PldRx.apply_to_ipc()` -> `.wraps_ipc()`.
- add a required `PldRx._ctx: Context` attr since it is needed
internally in some meths and each pld-rx now maps to a specific ctx.
- modify all recv methods to accept a `ipc: Context|MsgStream` (instead
of a `ctx` arg) since both have a ref to the same `._rx_chan` and there
are only a couple spots (in `.dec_msg()`) where we need the `ctx`
explicitly (which can now be easily accessed via a new `MsgStream.ctx`
property, see below).
- always show the `.dec_msg()` frame in tbs if there's a reference error
when calling `_raise_from_unexpected_msg()` in the fallthrough case.
- implement `limit_plds()` as light wrapper around getting the
`current_ipc_ctx()` and mutating its `MsgDec` via
`Context.pld_rx.limit_plds()`.
- add a `maybe_limit_plds()` which just provides an `@acm` equivalent of
`limit_plds()` handy for composing in a `async with ():` style block
(avoiding additional indent levels in the body of async funcs).
Obvi extend the `Context` and `MsgStream` interfaces as needed
to match the above:
- add a `Context.pld_rx` pub prop.
- new private refs to `Context._started_msg: Started` and
a `._started_pld` (mostly for internal debugging / testing / logging)
and set inside `.open_context()` immediately after the syncing phase.
- a `Context.has_outcome() -> bool:` predicate which can be used to more
easily determine if the ctx errored or has a final result.
- pub props for `MsgStream.ctx: Context` and `.chan: Channel` providing
full `ipc`-arg compat with the `PldRx` method signatures.
Proto-ing a little suite of call-stack-frame annotation-for-scanning
sub-systems for the purposes of both,
- the `.devx._debug`er and its
traceback and frame introspection needs when entering the REPL,
- detailed trace-style logging such that we can explicitly report
on "which and where" `tractor`'s APIs are used in the "app" code.
Deats:
- change mod name obvi from `._code` and adjust client mod imports.
- using `wrapt` (for perf) implement a `@api_frame` annot decorator
which both stashes per-call-stack-frame instances of `CallerInfo` in
a table and marks the function such that API endpoints can be easily
found via runtime stack scanning despite any internal impl changes.
- add a global `_frame2callerinfo_cache: dict[FrameType, CallerInfo]`
table for providing the per func-frame info caching.
- Re-implement `CallerInfo` to require less (types of) inputs:
|_ `_api_func: Callable`, a ref to the (singleton) func def.
|_ `_api_frame: FrameType` taken from the `@api_frame` marked `tractor`-API
func's runtime call-stack, from which we can determine the
app code's `.caller_frame`.
|_`_caller_frames_up: int|None` allowing the specific `@api_frame` to
determine "how many frames up" the application / calling code is.
And, a better set of derived attrs:
|_`caller_frame: FrameType` which finds and caches the API-eps calling
frame.
|_`caller_frame: FrameType` which finds and caches the API-eps calling
- add a new attempt at "getting a method ref from its runtime frame"
with `get_ns_and_func_from_frame()` using a heuristic that the
`CodeType.co_qualname: str` should have a "." in it for methods.
- main issue is still that the func-ref lookup will require searching
for the method's instance type by name, and that name isn't
guaranteed to be defined in any particular ns..
|_rn we try to read it from the `FrameType.f_locals` but that is
going to obvi fail any time the method is called in a module where
it's type is not also defined/imported.
- returns both the ns and the func ref FYI.
- set `._state._ctxvar_Context` just after `StartAck` inside
`open_context_from_portal()` so that `current_ipc_ctx()` always
works on the 'parent' side.
- always set `.canceller` to any `MsgTypeError.src_uid` and otherwise to
any maybe-detected `.src_uid` (i.e. for RAEs).
- always set `.canceller` to us when we rx a ctxc which reports us as
its canceller; this is a sanity check on definite "self cancellation".
- adjust `._is_self_cancelled()` logic to only be `True` when
`._remote_error` is both a ctxc with a `.canceller` set to us AND
when `Context.canceller` is also set to us (since the change above)
as a little bit of extra rigor.
- fill-in/fix some `.repr_state` edge cases:
- merge self-vs.-peer ctxc cases to one block and distinguish via
nested `._is_self_cancelled()` check.
- set 'errored' for all exception matched cases despite `.canceller`.
- add pre-`Return` phase statuses:
|_'pre-started' and 'syncing-to-child' depending on side and when
`._stream` has not (yet) been set.
|_'streaming' and 'streaming-finished' depending on side when
`._stream` is set and whether it was stopped/closed.
- tweak drainage log-message to use "outcome" instead of "result".
- use new `.devx.pformat.pformat_cs()` inside `_maybe_cancel_and_set_remote_error()`
but, IFF the log level is at least 'cancel'.
A better spot for the pretty-formatting of frame text (and thus tracebacks)
is in the new `.devx._code` module:
- move from `._exceptions` -> `.devx._code.pformat_boxed_tb()`.
- add new `pformat_caller_frame()` factored out the use case in
`._exceptions._mk_msg_type_err()` where we dump a stack trace
for bad `.send()` side IPC msgs.
Add some new pretty-format methods to `Context`:
- explicitly implement `.pformat()` and allow an `extra_fields: dict`
which can be used to inject additional fields (maybe eventually by
default) such as is now used inside
`._maybe_cancel_and_set_remote_error()` when reporting the internal
`._scope` state in cancel logging.
- add a new `.repr_state -> str` which provides a single string status
depending on the internal state of the IPC ctx in terms of the shuttle
protocol's "phase"; use it from `.pformat()` for the `|_state:`.
- set `.started(complain_no_parity=False)` now since we presume decoding
with `.pld: Raw` now with the new `PldRx` design.
- use new `msgops.current_pldrx()` in `mk_context()`.
As per much tinkering, re-designs and preceding rubber-ducking via many
"commit msg novelas", **finally** this adds the (hopefully) final
missing layer for typed msg safety: `tractor.msg._ops.PldRx`
(or `PayloadReceiver`? haven't decided how verbose to go..)
Design justification summary:
------ - ------
- need a way to be as-close-as-possible to the `tractor`-application
such that when `MsgType.pld: PayloadT` validation takes place, it is
straightforward and obvious how user code can decide to handle any
resulting `MsgTypeError`.
- there should be a common and optional-yet-modular way to modify
**how** data delivered via IPC (possibly embedded as user defined,
type-constrained `.pld: msgspec.Struct`s) can be handled and processed
during fault conditions and/or IPC "msg attacks".
- support for nested type constraints within a `MsgType.pld` field
should be simple to define, implement and understand at runtime.
- a layer between the app-level IPC primitive APIs
(`Context`/`MsgStream`) and application-task code (consumer code of
those APIs) should be easily customized and prove-to-be-as-such
through demonstrably rigorous internal (sub-sys) use!
-> eg. via seemless runtime RPC eps support like `Actor.cancel()`
-> by correctly implementing our `.devx._debug.Lock` REPL TTY mgmt
dialog prot, via a dead simple payload-as-ctl-msg-spec.
There are some fairly detailed doc strings included so I won't duplicate
that content, the majority of the work here is actually somewhat of
a factoring of many similar blocks that are doing more or less the same
`msg = await Context._rx_chan.receive()` with boilerplate for
`Error`/`Stop` handling via `_raise_from_no_key_in_msg()`. The new
`PldRx` basically provides a shim layer for this common "receive msg,
decode its payload, yield it up to the consuming app task" by pairing
the RPC feeder mem-chan with a msg-payload decoder and expecting IPC API
internals to use **one** API instead of re-implementing the same pattern
all over the place XD
`PldRx` breakdown
------ - ------
- for now only expects a `._msgdec: MsgDec` which allows for
override-able `MsgType.pld` validation and most obviously used in
the impl of `.dec_msg()`, the decode message method.
- provides multiple mem-chan receive options including:
|_ `.recv_pld()` which does the e2e operation of receiving a payload
item.
|_ a sync `.recv_pld_nowait()` version.
|_ a `.recv_msg_w_pld()` which optionally allows retreiving both the
shuttling `MsgType` as well as it's `.pld` body for use cases where
info on both is important (eg. draining a `MsgStream`).
Dirty internal changeover/implementation deatz:
------ - ------
- obvi move over all the IPC "primitives" that previously had the duplicate recv-n-yield
logic:
- `MsgStream.receive[_nowait]()` delegating instead to the equivalent
`PldRx.recv_pld[_nowait]()`.
- add `Context._pld_rx: PldRx`, created and passed in by
`mk_context()`; use it for the `.started()` -> `first: Started`
retrieval inside `open_context_from_portal()`.
- all the relevant `Portal` invocation methods: `.result()`,
`.run_from_ns()`, `.run()`; also allows for dropping `_unwrap_msg()`
and `.Portal_return_once()` outright Bo
- rename `Context.ctx._recv_chan` -> `._rx_chan`.
- add detailed `Context._scope` info for logging whether or not it's
cancelled inside `_maybe_cancel_and_set_remote_error()`.
- move `._context._drain_to_final_msg()` -> `._ops.drain_to_final_msg()`
since it's really not necessarily ctx specific per say, and it does
kinda fit with "msg operations" more abstractly ;)
As per some newly added features and APIs:
- pass `portal: Portal` to `Actor.start_remote_task()` from
`open_context_from_portal()` marking `Portal.open_context()` as
always being the "parent" task side.
- add caller tracing via `.devx._code.CallerInfo/.find_caller_info()`
called in `mk_context()` and (for now) a `__runtimeframe__: int = 2`
inside `open_context_from_portal()` such that any enter-er of
`Portal.open_context()` will be reported.
- pass in a new `._caller_info` attr which is used in 2 new meths:
- `.repr_caller: str` for showing the name of the app-code-func.
- `.repr_api: str` for showing the API ep, which for now we just
hardcode to `Portal.open_context()` since ow its gonna show the mod
func name `open_context_from_portal()`.
- use those new props ^ in the `._deliver_msg()` flow body log msg
content for much clearer msg-flow tracing Bo
- add `Context._cancel_on_msgerr: bool` to toggle whether
a delivered `MsgTypeError` should trigger a `._scope.cancel()` call.
- also (temporarily) add separate `.cancel()` emissions for both cases
as i work through hacking out the maybe `MsgType.pld: Raw` support.
Instead of `allow_msg_keys` since we've fully flipped over to
struct-types for msgs in the runtime.
- drop the loop from `MsgStream.receive_nowait()` since
`Yield/Return.pld` getting will handle both (instead of a loop of
`dict`-key reads).
Add a bit of special handling for msg-type-errors with a dedicated
log-msg detailing which `.side: str` is the sender/causer and avoiding
a `._scope.cancel()` call in such cases since the local task might be
written to handle and tolerate the badly (typed) IPC msg.
As part of ^, change the ctx task-pair "side" semantics from "caller" ->
"callee" to be "parent" -> "child" which better matches the
cross-process SC-linked-task supervision hierarchy, and
`trio.Nursery.parent_task`; in `trio` the task that opens a nursery is
also named the "parent".
Impl deats / fixes around the `.side` semantics:
- ensure that `._portal: Portal` is set ASAP after
`Actor.start_remote_task()` such that if the `Started` transaction
fails, the parent-vs.-child sides are still denoted correctly (since
`._portal` being set is the predicate for that).
- add a helper func `Context.peer_side(side: str) -> str:` which inverts
from "child" to "parent" and vice versa, useful for logging info.
Other tweaks:
- make `_drain_to_final_msg()` return a tuple of a maybe-`Return` and
the list of other `pre_result_drained: list[MsgType]` such that we
don't ever have to warn about the return msg getting captured as
a pre-"result" msg.
- Add some strictness flags to `.started()` which allow for toggling
whether to error or warn log about mismatching roundtripped `Started`
msgs prior to IPC transit.
Mostly removing commented (and replaced) code blocks lingering from the
ctxc semantics work and new typed-msg-spec `MsgType`s handling AND use
the new `._exceptions.pack_from_raise()` helper to construct
`StreamOverrun` msgs.
Deaterz:
- clean out the drain loop now that it's implemented to handle our
struct msg types including the `dict`-msg bits left in as
fallback-reminders, any notes/todos better summarized at the top of
their blocks, remove any `_final_result_is_set()` related duplicate/legacy
tidbits.
- use a `case Error()` block in drain loop with fallthrough to `_:`
always resulting in an rte raise.
- move "XXX" notes into the doc-string for `._deliver_msg()` as
a "rules" section.
- use `match:` syntax for logging the `result_or_err: MsgType` outcome
from the final `.result()` call inside `open_context_from_portal()`.
- generally speaking use `MsgType` type annotations throughout!
Better describes the internal RPC impl/latest-architecture with the msgs
delivered being those which either define a `.pld: PayloadT` that gets
passed up to user code, or the error-msg subset that similarly is raised
in a ctx-linked task.
As detailed in the surrounding notes, it's pretty advantageous to always
have the child context task ensure the first msg it relays back is
msg-type checked against the current spec and thus `MsgCodec`. Implement
the check via a simple codec-roundtrip of the `Started` msg such that
the `.pld` payload is always validated before transit. This ensures the
child will fail early and notify the parent before any streaming takes
place (i.e. the "nasty" dialog protocol phase).
The main motivation here is to avoid inter-actor task syncing bugs that
are hard(er) to recover from and/or such as if an invalid typed msg is
sent to the parent, who then ignores it (depending on config), and then
the child thinks the parent is in some presumed state while the parent
is still thinking a first msg has yet to arrive. Doing the stringent
check on the sender side (i.e. the child is sending the "first"
application msg via `.started()`) avoids/sidesteps dealing with such
syncing/coordinated-state problems by keeping the entire IPC dialog in
a "cheap" or "control" style transaction up until a stream is opened.
Iow, the parent task's `.open_context()` block entry can't occur until
the child side is definitely (as much as is possible with IPC msg type
checking) in a correct state spec wise. During any streaming phase in
the dialog the msg-type-checking is NOT done for performance (the
"nasty" protocol phase) and instead any type errors are relayed back
from the receiving side. I'm still unsure whether to take the same
approach on the `Return` msg, since at that point erroring early doesn't
benefit the parent task if/when a msg-type error occurs? Definitely more
to ponder and tinker out here..
Impl notes:
- a gotcha with the roundtrip-codec-ed msg is that it often won't match
the input `value` bc in the `msgpack` case many native python
sequence/collection types will map to a common array type due to the
surjection that `msgpack`'s type-sys imposes.
- so we can't assert that `started == rt_started` but it may be useful
to at least report the diff of the type-reduced payload so that the
caller can at least be notified how the input `value` might be
better type-casted prior to call, for ex. pre-casting to `list`s.
- added a `._strict_started: bool` that could provide the stringent
checking if desired in the future.
- on any validation error raise our `MsgTypeError` from it.
- ALSO change over the lingering `.send_yield()` deprecated meth body
to use a `Yield()`.
In the particular case of the `Portal.open_context().__aexit__()` frame,
due to usage of `contextlib.asynccontextmanager`, we can't easily hook
into monkeypatching a `__tracebackhide__` set nor catch-n-reraise around
the block exit without defining our own `.__aexit__()` impl. Thus, it's
prolly most sane to do something with an override of
`contextlib._AsyncGeneratorContextManager` or the public exposed
`AsyncContextDecorator` (which uses the former internally right?).
Also fixup some old `._invoke` mod paths in comments and just show
`str(eoc)` in `.open_stream().__aexit__()` terminated-by-EoC log msg
since the `repr()` form won't pprint the IPC msg nicely..
Where `.devx` is "developer experience", a hopefully broad enough subpkg
name for all the slick stuff planned to augment working on the actor
runtime 💥
Move the `._debug` module into the new subpkg and adjust rest of core
code base to reflect import path change. Also add a new
`.devx._debug.open_crash_handler()` manager for wrapping any sync code
outside a `trio.run()` which is handy for eventual CLI addons for
popular frameworks like `click`/`typer`.
- Remove `exceptiongroup` import,
- pin to py 3.11 in `setup.py`
- revert any lingering `tractor.devx` imports; sub-pkg is coming in
a downstream PR!
- remove weird double `@property` lingering from conflict reso..
- modern `pytest` requires conftest mod mods to be relative imported.
I swear long ago it used to operate this way but, I guess this finalizes
the design decision. It makes a lot more sense to *not* propagate any
`trio.EndOfChannel` raised from a `Context.open_stream() as stream:`
block when that EoC is due to graceful-explicit stream termination.
We use the EoC much like a `StopAsyncIteration` where the error
indicates termination of the stream due to either:
- reception of a stop IPC msg indicating the far end ended the stream
(gracecfully),
- closure of the underlying `Context._recv_chan` either by the runtime
or due to user code having called `MsgStream.aclose()`.
User code shouldn't expect to handle EoC outside the block since the
`@acm` having closed should indicate the exactly same lifetime state
(of said stream) ;)
Deats:
- add special EoC handler in `.open_stream()` which silently "absorbs"
the error only when the stream is already marked as closed (meaning
the EoC indeed corresponds to IPC closure) with an assert for now
ensuring the error is the same as set to `MsgStream._eoc`.
- in `MsgStream.receive()` break up the handlers for EoC and
`trio.ClosedResourceError` since the error instances are saved to
different variables and we **don't** want to rewrite the exception in
the eoc case (normally to mask `trio` internals in tbs) bc we need the
instance to be the exact one for doing checks inside
`.open_stream().__aexit__()` to absorb it.
Other surrounding "improvements":
- start using the new `Context.maybe_raise()` helper where it can easily
replace existing equivalent block-sections.
- use new `RemoteActorError.src_uid` as required.
Finally, since normally you need the content from `._context.Context`
and surroundings in order to effectively grok `Portal.open_context()`
anyways, might as well move the impl to the ctx module as
`open_context_from_portal()` and just bind it on the `Portal` class def.
Associated/required tweaks:
- avoid circ import on `.devx` by only import
`.maybe_wait_for_debugger()` when debug mode is set.
- drop `async_generator` usage, not sure why this hadn't already been
changed to `contextlib`?
- use `@acm` alias throughout `._portal`
Previously i was trying to approach this using lots of
`__tracebackhide__`'s in various internal funcs but since it's not
exactly straight forward to do this inside core deps like `trio` and the
stdlib, it makes a bit more sense to optionally catch and re-raise
certain classes of errors from their originals using `raise from` syntax
as per:
https://docs.python.org/3/library/exceptions.html#exception-context
Deats:
- litter `._context` methods with `__tracebackhide__`/`hide_tb` which
were previously being shown but that don't need to be to application
code now that cancel semantics testing is finished up.
- i originally did the same but later commented it all out in `._ipc`
since error catch and re-raise instead in higher level layers
(above the transport) seems to be a much saner approach.
- add catch-n-reraise-from in `MsgStream.send()`/.`receive()` to avoid
seeing the depths of `trio` and/or our `._ipc` layers on comms errors.
Further this patch adds some refactoring to use the
same remote-error shipper routine from both the actor-core in the RPC
invoker:
- rename it as `try_ship_error_to_remote()` and call it from
`._invoke()` as well as it's prior usage.
- make it optionally accept `cid: str` a `remote_descr: str` and of
course a `hide_tb: bool`.
Other misc tweaks:
- add some todo notes around `Actor.load_modules()` debug hooking.
- tweak the zombie reaper log msg and timeout value ;)
Tyler Goodlet
Guillermo Rodriguez