Source code for bluesky.plan_stubs

import itertools
import uuid
from cycler import cycler
import operator
from functools import reduce
from collections.abc import Iterable
import time
import warnings

try:
    # cytools is a drop-in replacement for toolz, implemented in Cython
    from cytools import partition
except ImportError:
    from toolz import partition

from .protocols import Locatable, Triggerable
from .utils import (
    get_hinted_fields,
    merge_cycler,
    separate_devices,
    all_safe_rewind,
    Msg,
    ensure_generator,
    short_uid as _short_uid,
)


[docs]def create(name='primary'): """ Bundle future readings into a new Event document. Parameters ---------- name : string, optional name given to event stream, used to convenient identification default is 'primary' Yields ------ msg : Msg Msg('create', name=name) See Also -------- :func:`bluesky.plan_stubs.save` """ return (yield Msg('create', name=name))
[docs]def save(): """ Close a bundle of readings and emit a completed Event document. Yields ------ msg : Msg Msg('save') See Also -------- :func:`bluesky.plan_stubs.create` """ return (yield Msg('save'))
[docs]def drop(): """ Drop a bundle of readings without emitting a completed Event document. Yields ------ msg : Msg Msg('drop') See Also -------- :func:`bluesky.plan_stubs.save` :func:`bluesky.plan_stubs.create` """ return (yield Msg('drop'))
[docs]def read(obj): """ Take a reading and add it to the current bundle of readings. Parameters ---------- obj : Device or Signal Yields ------ msg : Msg Msg('read', obj) """ return (yield Msg('read', obj))
[docs]def monitor(obj, *, name=None, **kwargs): """ Asynchronously monitor for new values and emit Event documents. Parameters ---------- obj : Signal args : passed through to ``obj.subscribe()`` name : string, optional name of event stream; default is None kwargs : passed through to ``obj.subscribe()`` Yields ------ msg : Msg ``Msg('monitor', obj, *args, **kwargs)`` See Also -------- :func:`bluesky.plan_stubs.unmonitor` """ return (yield Msg('monitor', obj, name=name, **kwargs))
[docs]def unmonitor(obj): """ Stop monitoring. Parameters ---------- obj : Signal Yields ------ msg : Msg Msg('unmonitor', obj) See Also -------- :func:`bluesky.plan_stubs.monitor` """ return (yield Msg('unmonitor', obj))
[docs]def null(): """ Yield a no-op Message. (Primarily for debugging and testing.) Yields ------ msg : Msg Msg('null') """ return (yield Msg('null'))
[docs]def abs_set(obj, *args, group=None, wait=False, **kwargs): """ Set a value. Optionally, wait for it to complete before continuing. Parameters ---------- obj : Device group : string (or any hashable object), optional identifier used by 'wait' wait : boolean, optional If True, wait for completion before processing any more messages. False by default. args : passed to obj.set() kwargs : passed to obj.set() Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.rel_set` :func:`bluesky.plan_stubs.wait` :func:`bluesky.plan_stubs.mv` """ if wait and group is None: group = str(uuid.uuid4()) ret = yield Msg('set', obj, *args, group=group, **kwargs) if wait: yield Msg('wait', None, group=group) return ret
[docs]def rel_set(obj, *args, group=None, wait=False, **kwargs): """ Set a value relative to current value. Optionally, wait before continuing. Parameters ---------- obj : Device group : string (or any hashable object), optional identifier used by 'wait'; None by default wait : boolean, optional If True, wait for completion before processing any more messages. False by default. args : passed to obj.set() kwargs : passed to obj.set() Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.abs_set` :func:`bluesky.plan_stubs.wait` """ from .preprocessors import relative_set_wrapper return ( yield from relative_set_wrapper( abs_set(obj, *args, group=group, wait=wait, **kwargs) ) )
[docs]def mv(*args, group=None, **kwargs): """ Move one or more devices to a setpoint. Wait for all to complete. If more than one device is specified, the movements are done in parallel. Parameters ---------- args : device1, value1, device2, value2, ... group : string, optional Used to mark these as a unit to be waited on. kwargs : passed to obj.set() Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.abs_set` :func:`bluesky.plan_stubs.mvr` """ group = group or str(uuid.uuid4()) status_objects = [] cyl = reduce(operator.add, [cycler(obj, [val]) for obj, val in partition(2, args)]) (step,) = merge_cycler(cyl) for obj, val in step.items(): ret = yield Msg('set', obj, val, group=group, **kwargs) status_objects.append(ret) yield Msg('wait', None, group=group) return tuple(status_objects)
mov = mv # synonym
[docs]def mvr(*args, group=None, **kwargs): """ Move one or more devices to a relative setpoint. Wait for all to complete. If more than one device is specified, the movements are done in parallel. Parameters ---------- args : device1, value1, device2, value2, ... group : string, optional Used to mark these as a unit to be waited on. kwargs : passed to obj.set() Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.rel_set` :func:`bluesky.plan_stubs.mv` """ objs = [] for obj, val in partition(2, args): objs.append(obj) from .preprocessors import relative_set_decorator @relative_set_decorator(objs) def inner_mvr(): return (yield from mv(*args, group=group, **kwargs)) return (yield from inner_mvr())
movr = mvr # synonym
[docs]def rd(obj, *, default_value=0): """Reads a single-value non-triggered object This is a helper plan to get the scalar value out of a Device (such as an EpicsMotor or a single EpicsSignal). For devices that implement the Locatable protocol, the location is canonical and is returned without parsing the read keys. For devices that have more than one read key the following rules are used: - if exactly 1 field is hinted that value is used - if no fields are hinted and there is exactly 1 value in the reading that value is used - if more than one field is hinted an Exception is raised - if no fields are hinted and there is more than one key in the reading an Exception is raised The devices is not triggered and this plan does not create any Events Parameters ---------- obj : Device The device to be read default_value : Any The value to return when not running in a "live" RunEngine. This come ups when :: ret = yield Msg('read', obj) assert ret is None the plan is passed to `list` or some other iterator that repeatedly sends `None` into the plan to advance the generator. Returns ------- val : Any or None The "single" value of the device """ # Location is canonical if it exists if isinstance(obj, Locatable): location = yield Msg("locate", obj) if location is None: # list-ify mode return default_value else: return location["readback"] hints = get_hinted_fields(obj) if len(hints) > 1: msg = ( f"Your object {obj} ({obj.name}.{getattr(obj, 'dotted_name', '')}) " f"has {len(hints)} items hinted ({hints}). We do not know how to " "pick out a single value. Please adjust the hinting by setting the " "kind of the components of this device or by reading one of its components" ) raise ValueError(msg) elif len(hints) == 0: hint = None if hasattr(obj, "read_attrs"): if len(obj.read_attrs) != 1: msg = ( f"Your object {obj} ({obj.name}.{getattr(obj, 'dotted_name', '')}) " f"and has {len(obj.read_attrs)} read attrs. We do not know how to " "pick out a single value. Please adjust the hinting/read_attrs by " "setting the kind of the components of this device or by reading one " "of its components" ) raise ValueError(msg) # len(hints) == 1 else: (hint,) = hints ret = yield from read(obj) # list-ify mode if ret is None: return default_value if hint is not None: return ret[hint]["value"] # handle the no hint 1 field case try: (data,) = ret.values() except ValueError as er: msg = ( f"Your object {obj} ({obj.name}.{getattr(obj, 'dotted_name', '')}) " f"and has {len(ret)} read values. We do not know how to pick out a " "single value. Please adjust the hinting/read_attrs by setting the " "kind of the components of this device or by reading one of its components" ) raise ValueError(msg) from er else: return data["value"]
[docs]def stop(obj): """ Stop a device. Parameters ---------- obj : Device Yields ------ msg : Msg """ return (yield Msg('stop', obj))
[docs]def trigger(obj, *, group=None, wait=False): """ Trigger and acquisition. Optionally, wait for it to complete. Parameters ---------- obj : Device group : string (or any hashable object), optional identifier used by 'wait'; None by default wait : boolean, optional If True, wait for completion before processing any more messages. False by default. Yields ------ msg : Msg """ ret = yield Msg('trigger', obj, group=group) if wait: yield Msg('wait', None, group=group) return ret
[docs]def sleep(time): """ Tell the RunEngine to sleep, while asynchronously doing other processing. This is not the same as ``import time; time.sleep()`` because it allows other actions, like interruptions, to be processed during the sleep. Parameters ---------- time : float seconds Yields ------ msg : Msg Msg('sleep', None, time) """ return (yield Msg('sleep', None, time))
[docs]def wait(group=None): """ Wait for all statuses in a group to report being finished. Parameters ---------- group : string (or any hashable object), optional Identifier given to `abs_set`, `rel_set`, `trigger`; None by default Yields ------ msg : Msg Msg('wait', None, group=group) """ return (yield Msg('wait', None, group=group))
_wait = wait # for internal references to avoid collision with 'wait' kwarg
[docs]def checkpoint(): """ If interrupted, rewind to this point. Yields ------ msg : Msg Msg('checkpoint') See Also -------- :func:`bluesky.plan_stubs.clear_checkpoint` """ return (yield Msg('checkpoint'))
[docs]def clear_checkpoint(): """ Designate that it is not safe to resume. If interrupted or paused, abort. Yields ------ msg : Msg Msg('clear_checkpoint') See Also -------- :func:`bluesky.plan_stubs.checkpoint` """ return (yield Msg('clear_checkpoint'))
[docs]def pause(): """ Pause and wait for the user to resume. Yields ------ msg : Msg Msg('pause') See Also -------- :func:`bluesky.plan_stubs.deferred_pause` :func:`bluesky.plan_stubs.sleep` """ return (yield Msg('pause', None, defer=False))
[docs]def deferred_pause(): """ Pause at the next checkpoint. Yields ------ msg : Msg Msg('pause', defer=True) See Also -------- :func:`bluesky.plan_stubs.pause` :func:`bluesky.plan_stubs.sleep` """ return (yield Msg('pause', None, defer=True))
[docs]def input_plan(prompt=''): """ Prompt the user for text input. Parameters ---------- prompt : str prompt string, e.g., 'enter user name' or 'enter next position' Yields ------ msg : Msg Msg('input', prompt=prompt) """ return (yield Msg('input', prompt=prompt))
[docs]def kickoff(obj, *, group=None, wait=False, **kwargs): """ Kickoff a fly-scanning device. Parameters ---------- obj : fly-able Device with 'kickoff', 'complete', and 'collect' methods group : string (or any hashable object), optional identifier used by 'wait' wait : boolean, optional If True, wait for completion before processing any more messages. False by default. kwargs passed through to ``obj.kickoff()`` Yields ------ msg : Msg Msg('kickoff', obj) See Also -------- :func:`bluesky.plan_stubs.complete` :func:`bluesky.plan_stubs.collect` :func:`bluesky.plan_stubs.wait` """ ret = (yield Msg('kickoff', obj, group=group, **kwargs)) if wait: yield from _wait(group=group) return ret
[docs]def complete(obj, *, group=None, wait=False, **kwargs): """ Tell a flyer, 'stop collecting, whenever you are ready'. The flyer returns a status object. Some flyers respond to this command by stopping collection and returning a finished status object immediately. Other flyers finish their given course and finish whenever they finish, irrespective of when this command is issued. Parameters ---------- obj : fly-able Device with 'kickoff', 'complete', and 'collect' methods group : string (or any hashable object), optional identifier used by 'wait' wait : boolean, optional If True, wait for completion before processing any more messages. False by default. kwargs passed through to ``obj.complete()`` Yields ------ msg : Msg a 'complete' Msg and maybe a 'wait' message See Also -------- :func:`bluesky.plan_stubs.kickoff` :func:`bluesky.plan_stubs.collect` :func:`bluesky.plan_stubs.wait` """ ret = yield Msg('complete', obj, group=group, **kwargs) if wait: yield from _wait(group=group) return ret
[docs]def collect(obj, *, stream=False, return_payload=True): """ Collect data cached by a fly-scanning device and emit documents. Parameters ---------- obj : fly-able Device with 'kickoff', 'complete', and 'collect' methods stream : boolean, optional If False (default), emit Event documents in one bulk dump. If True, emit events one at time. return_payload: boolean, optional If True (default), return the collected Events. If False, return None. Using ``stream=True`` and ``return_payload=False`` together avoids accumulating the documents in memory: they are emitted as they are collected, and they are not accumulated. Yields ------ msg : Msg Msg('collect', obj) See Also -------- :func:`bluesky.plan_stubs.kickoff` :func:`bluesky.plan_stubs.complete` :func:`bluesky.plan_stubs.wait` """ return (yield Msg('collect', obj, stream=stream, return_payload=return_payload))
[docs]def configure(obj, *args, **kwargs): """ Change Device configuration and emit an updated Event Descriptor document. Parameters ---------- obj : Device args passed through to ``obj.configure()`` kwargs passed through to ``obj.configure()`` Yields ------ msg : Msg ``Msg('configure', obj, *args, **kwargs)`` """ return (yield Msg('configure', obj, *args, **kwargs))
[docs]def stage(obj): """ 'Stage' a device (i.e., prepare it for use, 'arm' it). Parameters ---------- obj : Device Yields ------ msg : Msg Msg('stage', obj) See Also -------- :func:`bluesky.plan_stubs.unstage` """ return (yield Msg('stage', obj))
[docs]def unstage(obj): """ 'Unstage' a device (i.e., put it in standby, 'disarm' it). Parameters ---------- obj : Device Yields ------ msg : Msg Msg('unstage', obj) See Also -------- :func:`bluesky.plan_stubs.stage` """ return (yield Msg('unstage', obj))
[docs]def subscribe(name, func): """ Subscribe the stream of emitted documents. Parameters ---------- name : {'all', 'start', 'descriptor', 'event', 'stop'} func : callable Expected signature: ``f(name, doc)`` where ``name`` is one of the strings above ('all, 'start', ...) and ``doc`` is a dict Yields ------ msg : Msg Msg('subscribe', None, func, name) See Also -------- :func:`bluesky.plan_stubs.unsubscribe` """ return (yield Msg('subscribe', None, func, name))
[docs]def unsubscribe(token): """ Remove a subscription. Parameters ---------- token : int token returned by processing a 'subscribe' message Yields ------ msg : Msg Msg('unsubscribe', token=token) See Also -------- :func:`bluesky.plan_stubs.subscribe` """ return (yield Msg('unsubscribe', token=token))
[docs]def install_suspender(suspender): """ Install a suspender during a plan. Parameters ---------- suspender : :class:`bluesky.suspenders.SuspenderBase` The suspender to install Yields ------ msg : Msg Msg('install_suspender', None, suspender) See Also -------- :func:`bluesky.plan_stubs.remove_suspender` """ return (yield Msg('install_suspender', None, suspender))
[docs]def remove_suspender(suspender): """ Remove a suspender during a plan. Parameters ---------- suspender : :class:`bluesky.suspenders.SuspenderBase` The suspender to remove Yields ------ msg : Msg Msg('remove_suspender', None, suspender) See Also -------- :func:`bluesky.plan_stubs.install_suspender` """ return (yield Msg('remove_suspender', None, suspender))
[docs]def open_run(md=None): """ Mark the beginning of a new 'run'. Emit a RunStart document. Parameters ---------- md : dict, optional metadata Yields ------ msg : Msg ``Msg('open_run', **md)`` See Also -------- :func:`bluesky.plans_stubs.close_run` """ return (yield Msg('open_run', **(md or {})))
[docs]def close_run(exit_status=None, reason=None): """ Mark the end of the current 'run'. Emit a RunStop document. Parameters ---------- exit_status : {None, 'success', 'abort', 'fail'} The exit status to report in the Stop document reason : str, optional Long-form description of why the run ended Yields ------ msg : Msg Msg('close_run') See Also -------- :func:`bluesky.plans_stubs.open_run` """ return (yield Msg('close_run', exit_status=exit_status, reason=reason))
[docs]def wait_for(futures, **kwargs): """ Low-level: wait for a list of ``asyncio.Future`` objects to set (complete). Parameters ---------- futures : collection collection of asyncio.Future objects kwargs passed through to ``asyncio.wait()`` Yields ------ msg : Msg ``Msg('wait_for', None, futures, **kwargs)`` See Also -------- :func:`bluesky.plan_stubs.wait` """ return (yield Msg('wait_for', None, futures, **kwargs))
[docs]def trigger_and_read(devices, name='primary'): """ Trigger and read a list of detectors and bundle readings into one Event. Parameters ---------- devices : iterable devices to trigger (if they have a trigger method) and then read name : string, optional event stream name, a convenient human-friendly identifier; default name is 'primary' Yields ------ msg : Msg messages to 'trigger', 'wait' and 'read' """ from .preprocessors import contingency_wrapper # If devices is empty, don't emit 'create'/'save' messages. if not devices: yield from null() devices = separate_devices(devices) # remove redundant entries rewindable = all_safe_rewind(devices) # if devices can be re-triggered def inner_trigger_and_read(): grp = _short_uid('trigger') no_wait = True for obj in devices: if isinstance(obj, Triggerable): no_wait = False yield from trigger(obj, group=grp) # Skip 'wait' if none of the devices implemented a trigger method. if not no_wait: yield from wait(group=grp) yield from create(name) def read_plan(): ret = {} # collect and return readings to give plan access to them for obj in devices: reading = (yield from read(obj)) if reading is not None: ret.update(reading) return ret def standard_path(): yield from save() def exception_path(exp): yield from drop() raise exp ret = yield from contingency_wrapper( read_plan(), except_plan=exception_path, else_plan=standard_path ) return ret from .preprocessors import rewindable_wrapper return (yield from rewindable_wrapper(inner_trigger_and_read(), rewindable))
[docs]def broadcast_msg(command, objs, *args, **kwargs): """ Generate many copies of a message, applying it to a list of devices. Parameters ---------- command : string devices : iterable ``*args`` args for message ``**kwargs`` kwargs for message Yields ------ msg : Msg """ return_vals = [] for o in objs: ret = yield Msg(command, o, *args, **kwargs) return_vals.append(ret) return return_vals
[docs]def repeater(n, gen_func, *args, **kwargs): """ Generate n chained copies of the messages from gen_func Parameters ---------- n : int or None total number of repetitions; if None, infinite gen_func : callable returns generator instance ``*args`` args for gen_func ``**kwargs`` kwargs for gen_func Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.caching_repeater` """ it = range if n is None: n = 0 it = itertools.count for j in it(n): yield from gen_func(*args, **kwargs)
[docs]def caching_repeater(n, plan): """ Generate n chained copies of the messages in a plan. This is different from ``repeater`` above because it takes in a generator or iterator, not a function that returns one. Parameters ---------- n : int or None total number of repetitions; if None, infinite plan : iterable Yields ------ msg : Msg See Also -------- :func:`bluesky.plan_stubs.repeater` """ warnings.warn("The caching_repeater will be removed in a future version " "of bluesky.", stacklevel=2) if n is None: gen = itertools.count(0) else: gen = range(n) lst_plan = list(plan) for _ in gen: yield from (m for m in lst_plan)
[docs]def one_shot(detectors, take_reading=trigger_and_read): """Inner loop of a count. This is the default function for ``per_shot`` in count plans. Parameters ---------- detectors : Iterable[OphydObj] devices to read take_reading : plan, optional function to do the actual acquisition :: def take_reading(dets, name='primary'): yield from ... Callable[List[OphydObj], Optional[str]] -> Generator[Msg], optional Defaults to `trigger_and_read` """ yield Msg('checkpoint') yield from take_reading(list(detectors))
[docs]def one_1d_step(detectors, motor, step, take_reading=trigger_and_read): """ Inner loop of a 1D step scan This is the default function for ``per_step`` param in 1D plans. Parameters ---------- detectors : iterable devices to read motor : Settable The motor to move step : Any Where to move the motor to take_reading : plan, optional function to do the actual acquisition :: def take_reading(dets, name='primary'): yield from ... Callable[List[OphydObj], Optional[str]] -> Generator[Msg], optional Defaults to `trigger_and_read` """ def move(): grp = _short_uid('set') yield Msg('checkpoint') yield Msg('set', motor, step, group=grp) yield Msg('wait', None, group=grp) yield from move() return (yield from take_reading(list(detectors) + [motor]))
[docs]def move_per_step(step, pos_cache): """ Inner loop of an N-dimensional step scan without any readings This can be used as a building block for custom ``per_step`` stubs. Parameters ---------- step : dict mapping motors to positions in this step pos_cache : dict mapping motors to their last-set positions """ yield Msg('checkpoint') grp = _short_uid('set') for motor, pos in step.items(): if pos == pos_cache[motor]: # This step does not move this motor. continue yield Msg('set', motor, pos, group=grp) pos_cache[motor] = pos yield Msg('wait', None, group=grp)
[docs]def one_nd_step(detectors, step, pos_cache, take_reading=trigger_and_read): """ Inner loop of an N-dimensional step scan This is the default function for ``per_step`` param`` in ND plans. Parameters ---------- detectors : iterable devices to read step : dict mapping motors to positions in this step pos_cache : dict mapping motors to their last-set positions take_reading : plan, optional function to do the actual acquisition :: def take_reading(dets, name='primary'): yield from ... Callable[List[OphydObj], Optional[str]] -> Generator[Msg], optional Defaults to `trigger_and_read` """ motors = step.keys() yield from move_per_step(step, pos_cache) yield from take_reading(list(detectors) + list(motors))
[docs]def repeat(plan, num=1, delay=None): """ Repeat a plan num times with delay and checkpoint between each repeat. This is different from ``repeater`` and ``caching_repeater`` in that it adds ``checkpoint`` and optionally ``sleep`` messages if delay is provided. This is intended for users who need the structure of ``count`` but do not want to reimplement the control flow. Parameters ---------- plan: callable Callable that returns an iterable of Msg objects num : integer, optional number of readings to take; default is 1 If None, capture data until canceled delay : iterable or scalar, optional time delay between successive readings; default is 0 Notes ----- If ``delay`` is an iterable, it must have at least ``num - 1`` entries or the plan will raise a ``ValueError`` during iteration. """ # Create finite or infinite counter if num is None: iterator = itertools.count() else: iterator = range(num) # If delay is a scalar, repeat it forever. If it is an iterable, leave it. if not isinstance(delay, Iterable): delay = itertools.repeat(delay) else: try: num_delays = len(delay) except TypeError: # No way to tell in advance if we have enough delays. pass else: if num - 1 > num_delays: raise ValueError("num=%r but delays only provides %r " "entries" % (num, num_delays)) delay = iter(delay) def repeated_plan(): for i in iterator: now = time.time() # Intercept the flow in its earliest moment. yield Msg('checkpoint') yield from ensure_generator(plan()) try: d = next(delay) except StopIteration: if i + 1 == num: break elif num is None: break else: # num specifies a number of iterations less than delay raise ValueError("num=%r but delays only provides %r " "entries" % (num, i)) if d is not None: d = d - (time.time() - now) if d > 0: # Sleep if and only if time is left to do it. yield Msg('sleep', None, d) return (yield from repeated_plan())