By passing down the `tractor.hilevel.ServiceMngr.debug_mode: bool`
(normally proxied in from the `--pdb` CLI flag) to `spawn_brokerd()` and
adjusting the `_setup_persistent_brokerd()` endpoint to do the
`tractor.devx._debug.maybe_init_greenback()` if needed.
Also in the `broker_init()` factory merge all `tractor` related `kwargs`
(i.e. `start_actor_kwargs | datad_kwargs | spawn_kws`) into the 2nd
element returned as to be passed to `ActorNursery.start_actor()`. Start
re-naming some internal vars/fields as `datad` as well.
Such that we maintain that subsys in the actor-runtime repo (with
hopefully an extensive test suite XD).
Port deats,
- rewrite `open_service_mngr()` as a thin wrapper that delegates into
the new `tractor.hilevel.open_service_mngr()` but with maintenance of
the `Services` class-singleton for now.
- port `.service._daemon` usage to the new
`ServiceMngr.start_service_ctx()` a rename from
`.start_service_task()` which is now likely destined for the soon
supported `tractor.trionics.TaskMngr` nursery extension.
- ref the new `ServiceMngr.an: ActorNursery` instance var name.
Other,
- always enable the `tractor.pause_from_sync()` support via `greenback`
whenever `debug_mode` is set at `pikerd` init.
Nothing changing functionally here just adding more `tractor`
operational notes, tips for debug tooling and typing fixes B)
Of particular note is adding further details about the reason we do not
need to call `Context.cancel()` inside the `finally:` block of
`.open_context_in_task()` thanks to `tractor`'s new and improved
inter-actor cancellation semantics Bo
Since `tractor`'s new and improved inter-actor cancellation semantics
are much more pedantic, AND bc we use the `ServiceMngr` for spawning
service actors on-demand, the caller of `maybe_spawn_daemon()` should
NEVER conduct a so called "out of band" `Actor`-runtime cancel request
since this is precisely the job of our `ServiceMngr` XD
Add a super in depth note explaining the underlying issue and adding
a todo list of how we should prolly augment `tractor` to make such cases
easier to grok and fix in the future!
Given it's a fairly simple yet useful abstraction, it makes sense to
offer this sub-sys alongside the core `tractor` runtime lib.
Without going into extreme detail on the impl changes (it'll come in
the commit that moves to the other repo) here is the high level summary:
------ - ------
- rename `Services` -> `ServiceMngr` and use an factory `@acm`
to guarantee a single-instance-per-actor using a niche approach for a
singleton object using a default keyword-arg B)
- the mod level `open_service_mngr()` and `get_service_mngr()` are the
new allocation/access API.
- add a `ServiceMngr.start_service()` method which does the work of both
spawning a new subactor (for the daemon) and uses its portal to start
the mngr side supervision task.
- open actor/task nurseries inside the `@acm` allocator.
Adjust other dependent subsystems to match:
------ - ------
- use `open_service_mngr()` when first allocated in `open_pikerd()`.
- use `get_service_mngr()` instead of importing the class ref inside
`.service.maybe_spawn_daemon()`, `.brokers._daemon.spawn_brokerd()`
and `.data._sampling.spawn_samplerd()` using a `partial` to pack in
the endpoint ctx kwargs (unpacked inside `.start_service()` XD).
A new class var `tuple[Exception]` such that the err set can be reffed
externally as needed for catching other similar pub-sub/IPC failures in
other (related) real-time sub-systems.
Also added some now-masked logging for debugging live-feed stream reading
issues that should ONLY be used for debugging since they'll greatly
degrade HFT perf. Used the new `log.mk_repr()` stuff (that one day we
should prolly pull from `modden` as a dep) for pretty console emissions.
Since now `tractor` will raise this native `trio`-exc translated from
a `Stop` msg when the peer gracefully terminates a `tractor.MsgStream`.
Just `info()` log in such cases versus continuing to warn for the
others.
Tyler Goodlet
Nelson Torres