Add new task-scope oriented `PldRx.pld_spec` management API similar to
`.msg._codec.limit_msg_spec()`, but obvi built to process and filter
`MsgType.pld` values.
New API related changes include:
- new per-task singleton getter `msg._ops.current_pldrx()` which
delivers the current (global) payload receiver via a new
`_ctxvar_PldRx: ContextVar` configured with a default
`_def_any_pldec: MsgDec[Any]` decoder.
- a `PldRx.limit_plds()` which sets the decoder (`.type` underneath)
for the specific payload rx instance.
- `.msg._ops.limit_plds()` which obtains the current task-scoped `PldRx`
and applies the pld spec via a new `PldRx.limit_plds()`.
- rename `PldRx._msgdec` -> `._pldec`.
- add `.pld_dec` as pub attr for -^
Unrelated adjustments:
- use `.msg.pretty_struct.pformat()` where handy.
- always pass `expect_msg: MsgType`.
- add a `case Stop()` to `PldRx.dec_msg()` which will `log.warning()`
when a stop is received by no stream was open on this receiving side
since we rarely want that to raise since it's prolly just a runtime
race or mistake in user code.
Other:
Particularly when logging around `MsgTypeError`s.
Other:
- make `_raise_from_unexpected_msg()`'s `expect_msg` a non-default value
arg, must always be passed by caller.
- drop `'canceller'` from `_body_fields` ow it shows up twice for ctxc.
- use `.msg.pretty_struct.pformat()`.
- parameterize `RemoteActorError.reprol()` (repr-one-line method) to
show `RemoteActorError[<self.boxed_type_str>]( ..` to make obvi
the boxed remote error type.
- re-impl `.boxed_type_str` as `str`-casting the `.boxed_type` value
which is guaranteed to render non-`None`.
Basically exact same as that for `MsgCodec` with the `.spec` displayed
via a better (maybe multi-line) `.spec_str: str` generated from a common
new set of helper mod funcs factored out msg-codec meths:
- `mk_msgspec_table()` to gen a `MsgType` name -> msg table.
- `pformat_msgspec()` to `str`-ify said table values nicely.q
Also add a new `MsgCodec.msg_spec_str: str` prop which delegates to the
above for the same.
- tweaking logging to include more `MsgType` dumps on IPC faults.
- removing some commented cruft.
- comment formatting / cleanups / add-ons.
- more type annots.
- fill out some TODO content.
As per the reco:
https://jcristharif.com/msgspec/perf-tips.html#reusing-an-output-buffe
BUT, seems to cause this error in `pikerd`..
`BufferError: Existing exports of data: object cannot be re-sized`
Soo no idea? Maybe there's a tweak needed that we can glean from
tests/examples in the `msgspec` repo?
Disabling for now.
Instead of expecting it to be passed in (as it was prior), when
determining if a `Stop` msg is a valid end-of-channel signal use the
`ctx._stream: MsgStream|None` attr which **must** be set by any stream
opening API; either of:
- `Context.open_stream()`
- `Portal.open_stream_from()`
Adjust the case block logic to match with fallthrough from any EoC to
a closed error if necessary. Change the `_type: str` to match the
failing IPC-prim name in the tail case we raise a `MessagingError`.
Other:
- move `.sender: tuple` uid attr up to `RemoteActorError` since `Error`
optionally defines it as a field and for boxed `StreamOverrun`s (an
ignore case we check for in the runtime during cancellation) we want
it readable from the boxing rae.
- drop still unused `InternalActorError`.
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 ;)
In prep for a "payload receiver" abstraction that will wrap
`MsgType.pld`-IO delivery from `Context` and `MsgStream`, adds a small
`msgspec.msgpack.Decoder` shim which delegates an API similar to
`MsgCodec` and is offered via a `.msg._codec.mk_dec()` factory.
Detalles:
- move over the TODOs/comments from `.msg.types.Start` to to
`MsgDec.spec` since it's probably the ideal spot to start thinking
about it from a consumer code PoV.
- move codec reversion assert and log emit into `finally:` block.
- flip default `.types._tractor_codec = mk_codec_ipc_pld(ipc_pld_spec=Raw)`
in prep for always doing payload-delayed decodes.
- make `MsgCodec._dec` private with public property getter.
- change `CancelAck` to NOT derive from `Return` so it's mutex in
`match/case:` handling.
Since it's going to be used from the IPC primitive APIs
(`Context`/`MsgStream`) for similarly handling payload type spec
validation errors and bc it's really not well situation in the IPC
module XD
Summary of (impl) tweaks:
- obvi move `_mk_msg_type_err()` and import and use it in `._ipc`; ends
up avoiding a lot of ad-hoc imports we had from `._exceptions` anyway!
- mask out "new codec" runtime log emission from `MsgpackTCPStream`.
- allow passing a (coming in next commit) `codec: MsgDec` (message
decoder) which supports the same required `.pld_spec_str: str` attr.
- for send side logging use existing `MsgCodec..pformat_msg_spec()`.
- rename `_raise_from_no_key_in_msg()` to the now more appropriate
`_raise_from_unexpected_msg()`, but leaving alias for now.
Turns out we do want per-task inheritance particularly if there's to be
per `Context` dynamic mutation of the spec; we don't want mutation in
some task to affect any parent/global setting.
Turns out since we use a common "feeder task" in the rpc loop, we need to
offer a per `Context` payload decoder sys anyway in order to enable
per-task controls for inter-actor multi-task-ctx scenarios.
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.
Starting with a little sub-sys for tracing caller frames by marking them
with a dunder var (`__runtimeframe__` by default) and then scanning for
that frame such that code that is *calling* our APIs can be reported
easily in logging / tracing output.
New APIs:
- `find_caller_info()` which does the scan and delivers a,
- `CallerInfo` which (attempts) to expose both the runtime frame-info
and frame of the caller func along with `NamespacePath` properties.
Probably going to re-implement the dunder var bit as a decorator later
so we can bind in the literal func-object ref instead of trying to look
it up with `get_class_from_frame()`, since it's kinda hacky/non-general
and def doesn't work for closure funcs..
Breaks out all the (sub)actor local conc primitives from `Lock` (which
is now only used in and by the root actor) such that there's an explicit
distinction between a task that's "consuming" the `Lock` (remotely) vs.
the root-side service tasks which do the actual acquire on behalf of the
requesters.
`DebugStatus` changeover deats:
------ - ------
- move all the actor-local vars over `DebugStatus` including:
- move `_trio_handler` and `_orig_sigint_handler`
- `local_task_in_debug` now `repl_task`
- `_debugger_request_cs` now `req_cs`
- `local_pdb_complete` now `repl_release`
- drop all ^ fields from `Lock.repr()` obvi..
- move over the `.[un]shield_sigint()` and
`.is_main_trio_thread()` methods.
- add some new attrs/meths:
- `DebugStatus.repl` for the currently running `Pdb` in-actor
singleton.
- `.repr()` for pprint of state (like `Lock`).
- Note: that even when a root-actor task is in REPL, the `DebugStatus`
is still used for certain actor-local state mgmt, such as SIGINT
handler shielding.
- obvi change all lock-requester code bits to now use a `DebugStatus` in
their local actor-state instead of `Lock`, i.e. change usage from
`Lock` in `._runtime` and `._root`.
- use new `Lock.get_locking_task_cs()` API in when checking for
sub-in-debug from `._runtime.Actor._stream_handler()`.
Unrelated to topic-at-hand tweaks:
------ - ------
- drop the commented bits about hiding `@[a]cm` stack frames from
`_debug.pause()` and simplify to only one block with the `shield`
passthrough since we already solved the issue with cancel-scopes using
`@pdbp.hideframe` B)
- this includes all the extra logging about the extra frame for the
user (good thing i put in that wasted effort back then eh..)
- put the `try/except BaseException` with `log.exception()` around the
whole of `._pause()` to ensure we don't miss in-func errors which can
cause hangs..
- allow passing in `portal: Portal` to
`Actor.start_remote_task()` such that `Portal` task spawning methods
are always denoted correctly in terms of `Context.side`.
- lotsa logging tweaks, decreasing a bit of noise from `.runtime()`s.
Since it's totes possible to have a spec applied that won't permit
`str`s, might as well formalize a small msg set for subactors to request
the tree-wide TTY `Lock`.
BTW, I'm prolly not going into every single change here in this first
WIP since there's still a variety of broken stuff mostly to do with
races on the codec apply being done in a `trio.lowleve.RunVar`; it
should be re-done with a `ContextVar` such that each task does NOT
mutate the global setting..
New msg set and usage is simply:
- `LockStatus` which is the reponse msg delivered from `lock_tty_for_child()`
- `LockRelease` a one-off request msg from the subactor to drop the
`Lock` from a `MsgStream.send()`.
- use these msgs throughout the root and sub sides of the locking
ctx funcs: `lock_tty_for_child()` & `wait_for_parent_stdin_hijack()`
The codec is now applied in both the root and sub `Lock` request tasks:
- for root inside `lock_tty_for_child()` before the `.started()`.
- for subs, inside `wait_for_parent_stdin_hijack()` since we only want
to affect the codec *for the locking task*.
- (hence the need for ctx-var as mentioned above but currently this
can cause races which will break against other app tasks competing
for the codec setting).
- add a `apply_debug_codec()` helper for use in both cases.
- add more detailed logging to both the root and sub side of `Lock`
requesting funcs including requiring that the sub-side task "uid" (a
`tuple[str, int]` = (trio.Task.name, id(trio.Task)` be provided (more
on this later).
A main issue discovered while proto-testing all this was the ability of
a sub to "double lock" (leading to self-deadlock) via an error in
`wait_for_parent_stdin_hijack()` which, for ex., can happen in debug
mode via crash handling of a `MsgTypeError` received from the root
during a codec applied msg-spec race! Originally I was attempting to
solve this by making the SIGINT override handler more resilient but this
case is somewhat impossible to detect by an external root task other
then checking for duplicate ownership via the new `subactor_task_uid`.
=> SO NOW, we always stick the current task uid in the
`Lock._blocked: set` and raise an rte on a double request by the same
remote task.
Included is a variety of small refinements:
- finally figured out how to mark a variety of `.__exit__()` frames with
`pdbp.hideframe()` to actually hide them B)
- add cls methods around managing `Lock._locking_task_cs` from root only.
- re-org all the `Lock` attrs into those only used in root vs. subactors
and proto-prep a new `DebugStatus` actor-singleton to be used in subs.
- add a `Lock.repr()` to contextually print the current conc primitives.
- rename our `Pdb`-subtype to `PdbREPL`.
- rigor out the SIGINT handler a bit, originally to try and hack-solve
the double-lock issue mentioned above, but now just with better
logging and logic for most (all?) possible hang cases that should be
hang-recoverable after enough ctrl-c mashing by the user.. well
hopefully:
- using `Lock.repr()` for both root and sub cases.
- lots more `log.warn()`s and handler reversions on stale lock or cs
detection.
- factor `._pause()` impl a little better moving the actual repl entry
to a new `_enter_repl_sync()` (originally for easier wrapping in the
sub case with `apply_codec()`).
Since obvi we don't want to just only see the trace in the root most of
the time ;)
Currently the sig keeps firing twice in the root though, and i'm not
sure why yet..
- Drop `test_msg_spec_xor_pld_spec()` since we no longer support
`ipc_msg_spec` arg to `mk_codec()`.
- Expect `MsgTypeError`s around `.open_context()` calls when
`add_codec_hooks == False`.
- toss in some `.pause()` points in the subactor ctx body whilst hacking
out a `.pld` protocol for debug mode TTY locking.
Such that the top level `maybe_enable_greenback` from
`open_root_actor()` can toggle the entire actor tree's usage.
Read the rtv in `._rpc` tasks and only enable if set.
Also, rigor up the `._rpc.process_messages()` loop to handle `Error()`
and `case _:` separately such that we now raise an explicit rte for
unknown / invalid msgs. Use "parent" / "child" for side descriptions in
loop comments and put a fat comment before the `StartAck` in `_invoke()`.
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).
Which matches with renaming `.payload_msg` -> `.expected_msg` which is
the value we attempt to construct from a vanilla-msgppack
decode-to-`dict` and then construct manually into a `MsgType` using
`.msg.types.from_dict_msg()`. Add a todo to use new `use_pretty` flag
which currently conflicts with `._exceptions.pformat_boxed_type()`
prefix formatting..
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.
Display the new `MsgCodec.pld_spec_str` and format the incorrect field
value to be placed entirely (txt block wise) right of the "type annot"
part of the line:
Iow if you had a bad `dict` value where something else should be it'd
look something like this:
<Started(
|_pld: NamespacePath = {'cid': '3e0ca00c-7d32-4d2a-a0c2-ac2e12453871',
'locked': True,
'msg_type': 'LockStatus',
'subactor_uid': ['sub', 'af7ccb69-1dab-491f-84f7-2ec42c32d137']}
- add some `tb_str: str` indent-prefix args for diff indent levels for the
body vs. the surrounding "ascii box".
- ^-use it-^ from `RemoteActorError.__repr()__` obvi.
- use new `msg.types.from_dict_msg()` in impl of
`MsgTypeError.payload_msg`, handy for showing what the message "would
have looked like in `Struct` form" had it not failed it's type
constraints.
Sure makes console grokability a lot better by showing only the
customizeable fields.
Further, clean up `mk_codec()` a bunch by removing the `ipc_msg_spec`
param since we don't plan to support another msg-set (for now) which
allows cleaning out a buncha logic that was mostly just a source of
bugs..
Also,
- add temporary `log.info()` around codec application.
- throw in some sanity `assert`s to `limit_msg_spec()`.
- add but mask out the `extend_msg_spec()` idea since it seems `msgspec`
won't allow `Decoder.type` extensions when using a custom `dec_hook()`
for some extension type.. (not sure what approach to take here yet).
Handy for re-constructing a struct-`MsgType` from a `dict` decoded from
wire-bytes wherein the msg failed to decode normally due to a field type
error but you'd still like to show the "potential" msg in struct form,
say inside a `MsgTypeError`'s meta data.
Supporting deats:
- add a `.msg.types.from_dict_msg()` to implement it (the helper).
- also a `.msg.types._msg_table: dict[str, MsgType]` for supporting this
func ^ as well as providing just a general `MsgType`-by-`str`-name
lookup.
Unrelated:
- Drop commented idea for still supporting `dict`-msg set via
`enc/dec_hook()`s that would translate to/from `MsgType`s, but that
would require a duplicate impl in the runtime.. so eff that XD
Tyler Goodlet