piker/piker/fsp/_engine.py

456 lines
14 KiB
Python

# piker: trading gear for hackers
# Copyright (C) Tyler Goodlet (in stewardship of pikers)
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
'''
core task logic for processing chains
'''
from dataclasses import dataclass
from functools import partial
from typing import (
AsyncIterator, Callable, Optional,
Union,
)
import numpy as np
import pyqtgraph as pg
import trio
from trio_typing import TaskStatus
import tractor
from tractor.msg import NamespacePath
from ..log import get_logger, get_console_log
from .. import data
from ..data import attach_shm_array
from ..data.feed import Feed
from ..data._sharedmem import ShmArray
from ..data._source import Symbol
from ._api import (
Fsp,
_load_builtins,
_Token,
)
log = get_logger(__name__)
@dataclass
class TaskTracker:
complete: trio.Event
cs: trio.CancelScope
async def filter_quotes_by_sym(
sym: str,
quote_stream: tractor.MsgStream,
) -> AsyncIterator[dict]:
'''
Filter quote stream by target symbol.
'''
# TODO: make this the actual first quote from feed
# XXX: this allows for a single iteration to run for history
# processing without waiting on the real-time feed for a new quote
yield {}
async for quotes in quote_stream:
quote = quotes.get(sym)
if quote:
yield quote
async def fsp_compute(
symbol: Symbol,
feed: Feed,
quote_stream: trio.abc.ReceiveChannel,
src: ShmArray,
dst: ShmArray,
func: Callable,
# attach_stream: bool = False,
task_status: TaskStatus[None] = trio.TASK_STATUS_IGNORED,
) -> None:
profiler = pg.debug.Profiler(
delayed=False,
disabled=True
)
fqsn = symbol.front_fqsn()
out_stream = func(
# TODO: do we even need this if we do the feed api right?
# shouldn't a local stream do this before we get a handle
# to the async iterable? it's that or we do some kinda
# async itertools style?
filter_quotes_by_sym(fqsn, quote_stream),
# XXX: currently the ``ohlcv`` arg
feed.shm,
)
# Conduct a single iteration of fsp with historical bars input
# and get historical output
history_output: Union[
dict[str, np.ndarray], # multi-output case
np.ndarray, # single output case
]
history_output = await out_stream.__anext__()
func_name = func.__name__
profiler(f'{func_name} generated history')
# build struct array with an 'index' field to push as history
# TODO: push using a[['f0', 'f1', .., 'fn']] = .. syntax no?
# if the output array is multi-field then push
# each respective field.
fields = getattr(dst.array.dtype, 'fields', None).copy()
fields.pop('index')
history: Optional[np.ndarray] = None # TODO: nptyping here!
if fields and len(fields) > 1 and fields:
if not isinstance(history_output, dict):
raise ValueError(
f'`{func_name}` is a multi-output FSP and should yield a '
'`dict[str, np.ndarray]` for history'
)
for key in fields.keys():
if key in history_output:
output = history_output[key]
if history is None:
if output is None:
length = len(src.array)
else:
length = len(output)
# using the first output, determine
# the length of the struct-array that
# will be pushed to shm.
history = np.zeros(
length,
dtype=dst.array.dtype
)
if output is None:
continue
history[key] = output
# single-key output stream
else:
if not isinstance(history_output, np.ndarray):
raise ValueError(
f'`{func_name}` is a single output FSP and should yield an '
'`np.ndarray` for history'
)
history = np.zeros(
len(history_output),
dtype=dst.array.dtype
)
history[func_name] = history_output
# TODO: XXX:
# THERE'S A BIG BUG HERE WITH THE `index` field since we're
# prepending a copy of the first value a few times to make
# sub-curves align with the parent bar chart.
# This likely needs to be fixed either by,
# - manually assigning the index and historical data
# seperately to the shm array (i.e. not using .push())
# - developing some system on top of the shared mem array that
# is `index` aware such that historical data can be indexed
# relative to the true first datum? Not sure if this is sane
# for incremental compuations.
first = dst._first.value = src._first.value
# TODO: can we use this `start` flag instead of the manual
# setting above?
index = dst.push(history, start=first)
profiler(f'{func_name} pushed history')
profiler.finish()
# setup a respawn handle
with trio.CancelScope() as cs:
# TODO: might be better to just make a "restart" method where
# the target task is spawned implicitly and then the event is
# set via some higher level api? At that poing we might as well
# be writing a one-cancels-one nursery though right?
tracker = TaskTracker(trio.Event(), cs)
task_status.started((tracker, index))
profiler(f'{func_name} yield last index')
# import time
# last = time.time()
try:
async for processed in out_stream:
log.debug(f"{func_name}: {processed}")
key, output = processed
index = src.index
dst.array[-1][key] = output
# NOTE: for now we aren't streaming this to the consumer
# stream latest array index entry which basically just acts
# as trigger msg to tell the consumer to read from shm
# TODO: further this should likely be implemented much
# like our `Feed` api where there is one background
# "service" task which computes output and then sends to
# N-consumers who subscribe for the real-time output,
# which we'll likely want to implement using local-mem
# chans for the fan out?
# if attach_stream:
# await client_stream.send(index)
# period = time.time() - last
# hz = 1/period if period else float('nan')
# if hz > 60:
# log.info(f'FSP quote too fast: {hz}')
# last = time.time()
finally:
tracker.complete.set()
@tractor.context
async def cascade(
ctx: tractor.Context,
# data feed key
fqsn: str,
src_shm_token: dict,
dst_shm_token: tuple[str, np.dtype],
ns_path: NamespacePath,
shm_registry: dict[str, _Token],
zero_on_step: bool = False,
loglevel: Optional[str] = None,
) -> None:
'''
Chain streaming signal processors and deliver output to
destination shm array buffer.
'''
profiler = pg.debug.Profiler(
delayed=False,
disabled=False
)
if loglevel:
get_console_log(loglevel)
src = attach_shm_array(token=src_shm_token)
dst = attach_shm_array(readonly=False, token=dst_shm_token)
reg = _load_builtins()
lines = '\n'.join([f'{key.rpartition(":")[2]} => {key}' for key in reg])
log.info(
f'Registered FSP set:\n{lines}'
)
# update actorlocal flows table which registers
# readonly "instances" of this fsp for symbol/source
# so that consumer fsps can look it up by source + fsp.
# TODO: ugh i hate this wind/unwind to list over the wire
# but not sure how else to do it.
for (token, fsp_name, dst_token) in shm_registry:
Fsp._flow_registry[
(_Token.from_msg(token), fsp_name)
] = _Token.from_msg(dst_token)
fsp: Fsp = reg.get(
NamespacePath(ns_path)
)
func = fsp.func
if not func:
# TODO: assume it's a func target path
raise ValueError(f'Unknown fsp target: {ns_path}')
# open a data feed stream with requested broker
async with data.feed.maybe_open_feed(
[fqsn],
# TODO throttle tick outputs from *this* daemon since
# it'll emit tons of ticks due to the throttle only
# limits quote arrival periods, so the consumer of *this*
# needs to get throttled the ticks we generate.
# tick_throttle=60,
) as (feed, quote_stream):
symbol = feed.symbols[fqsn]
profiler(f'{func}: feed up')
assert src.token == feed.shm.token
# last_len = new_len = len(src.array)
func_name = func.__name__
async with (
trio.open_nursery() as n,
):
fsp_target = partial(
fsp_compute,
symbol=symbol,
feed=feed,
quote_stream=quote_stream,
# shm
src=src,
dst=dst,
# target
func=func
)
tracker, index = await n.start(fsp_target)
if zero_on_step:
last = dst.array[-1:]
zeroed = np.zeros(last.shape, dtype=last.dtype)
profiler(f'{func_name}: fsp up')
# sync client
await ctx.started(index)
# XXX: rt stream with client which we MUST
# open here (and keep it open) in order to make
# incremental "updates" as history prepends take
# place.
async with ctx.open_stream() as client_stream:
# TODO: these likely should all become
# methods of this ``TaskLifetime`` or wtv
# abstraction..
async def resync(
tracker: TaskTracker,
) -> tuple[TaskTracker, int]:
# TODO: adopt an incremental update engine/approach
# where possible here eventually!
log.warning(f're-syncing fsp {func_name} to source')
tracker.cs.cancel()
await tracker.complete.wait()
tracker, index = await n.start(fsp_target)
# always trigger UI refresh after history update,
# see ``piker.ui._fsp.FspAdmin.open_chain()`` and
# ``piker.ui._display.trigger_update()``.
await client_stream.send('update')
return tracker, index
def is_synced(
src: ShmArray,
dst: ShmArray
) -> tuple[bool, int, int]:
'''Predicate to dertmine if a destination FSP
output array is aligned to its source array.
'''
step_diff = src.index - dst.index
len_diff = abs(len(src.array) - len(dst.array))
return not (
# the source is likely backfilling and we must
# sync history calculations
len_diff > 2 or
# we aren't step synced to the source and may be
# leading/lagging by a step
step_diff > 1 or
step_diff < 0
), step_diff, len_diff
async def poll_and_sync_to_step(
tracker: TaskTracker,
src: ShmArray,
dst: ShmArray,
) -> tuple[TaskTracker, int]:
synced, step_diff, _ = is_synced(src, dst)
while not synced:
tracker, index = await resync(tracker)
synced, step_diff, _ = is_synced(src, dst)
return tracker, step_diff
s, step, ld = is_synced(src, dst)
# detect sample period step for subscription to increment
# signal
times = src.array['time']
delay_s = times[-1] - times[times != times[-1]][-1]
# Increment the underlying shared memory buffer on every
# "increment" msg received from the underlying data feed.
async with feed.index_stream(
int(delay_s)
) as istream:
profiler(f'{func_name}: sample stream up')
profiler.finish()
async for _ in istream:
# respawn the compute task if the source
# array has been updated such that we compute
# new history from the (prepended) source.
synced, step_diff, _ = is_synced(src, dst)
if not synced:
tracker, step_diff = await poll_and_sync_to_step(
tracker,
src,
dst,
)
# skip adding a last bar since we should already
# be step alinged
if step_diff == 0:
continue
# read out last shm row, copy and write new row
array = dst.array
# some metrics like vlm should be reset
# to zero every step.
if zero_on_step:
last = zeroed
else:
last = array[-1:].copy()
dst.push(last)