class AfterCount(TriggerFn):
"""Fire when there are at least count elements in this window pane.
AfterCount is experimental. No backwards compatibility guarantees.
"""
COUNT_TAG = _CombiningValueStateTag('count', combiners.CountCombineFn())
def __init__(self, count):
if not isinstance(count, numbers.Integral) or count < 1:
raise ValueError("count (%d) must be a positive integer." % count)
self.count = count
def __repr__(self):
return 'AfterCount(%s)' % self.count
def __eq__(self, other):
return type(self) == type(other) and self.count == other.count
def __hash__(self):
return hash(self.count)
def on_element(self, element, window, context):
context.add_state(self.COUNT_TAG, 1)
def on_merge(self, to_be_merged, merge_result, context):
# states automatically merged
pass
def should_fire(self, time_domain, watermark, window, context):
return context.get_state(self.COUNT_TAG) >= self.count
def on_fire(self, watermark, window, context):
return True
def reset(self, window, context):
context.clear_state(self.COUNT_TAG)
@staticmethod
def from_runner_api(proto, unused_context):
return AfterCount(proto.element_count.element_count)
def to_runner_api(self, unused_context):
return beam_runner_api_pb2.Trigger(
element_count=beam_runner_api_pb2.Trigger.ElementCount(
element_count=self.count))
def has_ontime_pane(self):
return False
class AfterCount(TriggerFn):
"""Fire when there are at least count elements in this window pane."""
COUNT_TAG = _CombiningValueStateTag('count', combiners.CountCombineFn())
def __init__(self, count):
self.count = count
def __repr__(self):
return 'AfterCount(%s)' % self.count
def __eq__(self, other):
return type(self) == type(other) and self.count == other.count
def on_element(self, element, window, context):
context.add_state(self.COUNT_TAG, 1)
def on_merge(self, to_be_merged, merge_result, context):
# states automatically merged
pass
def should_fire(self, watermark, window, context):
return context.get_state(self.COUNT_TAG) >= self.count
def on_fire(self, watermark, window, context):
return True
def reset(self, window, context):
context.clear_state(self.COUNT_TAG)
@staticmethod
def from_runner_api(proto, unused_context):
return AfterCount(proto.element_count.element_count)
def to_runner_api(self, unused_context):
return beam_runner_api_pb2.Trigger(
element_count=beam_runner_api_pb2.Trigger.ElementCount(
element_count=self.count))
class GeneralTriggerDriver(TriggerDriver):
"""Breaks a series of bundle and timer firings into window (pane)s.
Suitable for all variants of Windowing.
"""
ELEMENTS = ListStateTag('elements')
TOMBSTONE = CombiningValueStateTag('tombstone', combiners.CountCombineFn())
def __init__(self, windowing):
self.window_fn = windowing.windowfn
self.output_time_fn_impl = OutputTimeFn.get_impl(windowing.output_time_fn,
self.window_fn)
# pylint: disable=invalid-name
self.WATERMARK_HOLD = WatermarkHoldStateTag('watermark',
self.output_time_fn_impl)
# pylint: enable=invalid-name
self.trigger_fn = windowing.triggerfn
self.accumulation_mode = windowing.accumulation_mode
self.is_merging = True
def process_elements(self, state, windowed_values, output_watermark):
if self.is_merging:
state = MergeableStateAdapter(state)
windows_to_elements = collections.defaultdict(list)
for wv in windowed_values:
for window in wv.windows:
windows_to_elements[window].append((wv.value, wv.timestamp))
# First handle merging.
if self.is_merging:
old_windows = set(state.known_windows())
all_windows = old_windows.union(windows_to_elements.keys())
if all_windows != old_windows:
merged_away = {}
class TriggerMergeContext(WindowFn.MergeContext):
def merge(_, to_be_merged, merge_result): # pylint: disable=no-self-argument
for window in to_be_merged:
if window != merge_result:
merged_away[window] = merge_result
state.merge(to_be_merged, merge_result)
# using the outer self argument.
self.trigger_fn.on_merge(
to_be_merged, merge_result, state.at(merge_result))
self.window_fn.merge(TriggerMergeContext(all_windows))
merged_windows_to_elements = collections.defaultdict(list)
for window, values in windows_to_elements.items():
while window in merged_away:
window = merged_away[window]
merged_windows_to_elements[window].extend(values)
windows_to_elements = merged_windows_to_elements
for window in merged_away:
state.clear_state(window, self.WATERMARK_HOLD)
# Next handle element adding.
for window, elements in windows_to_elements.items():
if state.get_state(window, self.TOMBSTONE):
continue
# Add watermark hold.
# TODO(ccy): Add late data and garbage-collection hold support.
output_time = self.output_time_fn_impl.merge(
window,
(element_output_time for element_output_time in
(self.output_time_fn_impl.assign_output_time(window, timestamp)
for unused_value, timestamp in elements)
if element_output_time >= output_watermark))
if output_time is not None:
state.add_state(window, self.WATERMARK_HOLD, output_time)
context = state.at(window)
for value, unused_timestamp in elements:
state.add_state(window, self.ELEMENTS, value)
self.trigger_fn.on_element(value, window, context)
# Maybe fire this window.
watermark = MIN_TIMESTAMP
if self.trigger_fn.should_fire(watermark, window, context):
finished = self.trigger_fn.on_fire(watermark, window, context)
yield self._output(window, finished, state)
def process_timer(self, window_id, unused_name, time_domain, timestamp,
state):
if self.is_merging:
state = MergeableStateAdapter(state)
window = state.get_window(window_id)
if state.get_state(window, self.TOMBSTONE):
return
if time_domain == TimeDomain.WATERMARK:
if not self.is_merging or window in state.known_windows():
context = state.at(window)
if self.trigger_fn.should_fire(timestamp, window, context):
finished = self.trigger_fn.on_fire(timestamp, window, context)
yield self._output(window, finished, state)
else:
raise Exception('Unexpected time domain: %s' % time_domain)
def _output(self, window, finished, state):
"""Output window and clean up if appropriate."""
values = state.get_state(window, self.ELEMENTS)
if finished:
# TODO(robertwb): allowed lateness
state.clear_state(window, self.ELEMENTS)
state.add_state(window, self.TOMBSTONE, 1)
elif self.accumulation_mode == AccumulationMode.DISCARDING:
state.clear_state(window, self.ELEMENTS)
timestamp = state.get_state(window, self.WATERMARK_HOLD)
if timestamp is None:
# If no watermark hold was set, output at end of window.
timestamp = window.end
else:
state.clear_state(window, self.WATERMARK_HOLD)
return WindowedValue(values, timestamp, (window,))
class GeneralTriggerDriver(TriggerDriver):
"""Breaks a series of bundle and timer firings into window (pane)s.
Suitable for all variants of Windowing.
"""
ELEMENTS = _ListStateTag('elements')
TOMBSTONE = _CombiningValueStateTag('tombstone', combiners.CountCombineFn())
INDEX = _CombiningValueStateTag('index', combiners.CountCombineFn())
NONSPECULATIVE_INDEX = _CombiningValueStateTag(
'nonspeculative_index', combiners.CountCombineFn())
def __init__(self, windowing, clock):
self.clock = clock
self.allowed_lateness = windowing.allowed_lateness
self.window_fn = windowing.windowfn
self.timestamp_combiner_impl = TimestampCombiner.get_impl(
windowing.timestamp_combiner, self.window_fn)
# pylint: disable=invalid-name
self.WATERMARK_HOLD = _WatermarkHoldStateTag(
'watermark', self.timestamp_combiner_impl)
# pylint: enable=invalid-name
self.trigger_fn = windowing.triggerfn
self.accumulation_mode = windowing.accumulation_mode
self.is_merging = True
def process_elements(
self,
state,
windowed_values,
output_watermark,
input_watermark=MIN_TIMESTAMP):
if self.is_merging:
state = MergeableStateAdapter(state)
windows_to_elements = collections.defaultdict(list)
for wv in windowed_values:
for window in wv.windows:
# ignore expired windows
if input_watermark > window.end + self.allowed_lateness:
continue
windows_to_elements[window].append((wv.value, wv.timestamp))
# First handle merging.
if self.is_merging:
old_windows = set(state.known_windows())
all_windows = old_windows.union(list(windows_to_elements))
if all_windows != old_windows:
merged_away = {}
class TriggerMergeContext(WindowFn.MergeContext):
def merge(_, to_be_merged, merge_result): # pylint: disable=no-self-argument
for window in to_be_merged:
if window != merge_result:
merged_away[window] = merge_result
# Clear state associated with PaneInfo since it is
# not preserved across merges.
state.clear_state(window, self.INDEX)
state.clear_state(window, self.NONSPECULATIVE_INDEX)
state.merge(to_be_merged, merge_result)
# using the outer self argument.
self.trigger_fn.on_merge(
to_be_merged, merge_result, state.at(merge_result, self.clock))
self.window_fn.merge(TriggerMergeContext(all_windows))
merged_windows_to_elements = collections.defaultdict(list)
for window, values in windows_to_elements.items():
while window in merged_away:
window = merged_away[window]
merged_windows_to_elements[window].extend(values)
windows_to_elements = merged_windows_to_elements
for window in merged_away:
state.clear_state(window, self.WATERMARK_HOLD)
# Next handle element adding.
for window, elements in windows_to_elements.items():
if state.get_state(window, self.TOMBSTONE):
continue
# Add watermark hold.
# TODO(ccy): Add late data and garbage-collection hold support.
output_time = self.timestamp_combiner_impl.merge(
window,
(
element_output_time for element_output_time in (
self.timestamp_combiner_impl.assign_output_time(
window, timestamp) for unused_value,
timestamp in elements)
if element_output_time >= output_watermark))
if output_time is not None:
state.add_state(window, self.WATERMARK_HOLD, output_time)
context = state.at(window, self.clock)
for value, unused_timestamp in elements:
state.add_state(window, self.ELEMENTS, value)
self.trigger_fn.on_element(value, window, context)
# Maybe fire this window.
if self.trigger_fn.should_fire(TimeDomain.WATERMARK,
input_watermark,
window,
context):
finished = self.trigger_fn.on_fire(input_watermark, window, context)
yield self._output(
window, finished, state, input_watermark, output_watermark, False)
def process_timer(
self,
window_id,
unused_name,
time_domain,
timestamp,
state,
input_watermark=None):
if input_watermark is None:
input_watermark = timestamp
if self.is_merging:
state = MergeableStateAdapter(state)
window = state.get_window(window_id)
if state.get_state(window, self.TOMBSTONE):
return
if time_domain in (TimeDomain.WATERMARK, TimeDomain.REAL_TIME):
if not self.is_merging or window in state.known_windows():
context = state.at(window, self.clock)
if self.trigger_fn.should_fire(time_domain, timestamp, window, context):
finished = self.trigger_fn.on_fire(timestamp, window, context)
yield self._output(
window,
finished,
state,
input_watermark,
timestamp,
time_domain == TimeDomain.WATERMARK)
else:
raise Exception('Unexpected time domain: %s' % time_domain)
def _output(
self,
window,
finished,
state,
input_watermark,
output_watermark,
maybe_ontime):
"""Output window and clean up if appropriate."""
index = state.get_state(window, self.INDEX)
state.add_state(window, self.INDEX, 1)
if output_watermark <= window.max_timestamp():
nonspeculative_index = -1
timing = windowed_value.PaneInfoTiming.EARLY
if state.get_state(window, self.NONSPECULATIVE_INDEX):
nonspeculative_index = state.get_state(
window, self.NONSPECULATIVE_INDEX)
state.add_state(window, self.NONSPECULATIVE_INDEX, 1)
_LOGGER.warning(
'Watermark moved backwards in time '
'or late data moved window end forward.')
else:
nonspeculative_index = state.get_state(window, self.NONSPECULATIVE_INDEX)
state.add_state(window, self.NONSPECULATIVE_INDEX, 1)
timing = (
windowed_value.PaneInfoTiming.ON_TIME if maybe_ontime and
nonspeculative_index == 0 else windowed_value.PaneInfoTiming.LATE)
pane_info = windowed_value.PaneInfo(
index == 0, finished, timing, index, nonspeculative_index)
values = state.get_state(window, self.ELEMENTS)
if finished:
# TODO(robertwb): allowed lateness
state.clear_state(window, self.ELEMENTS)
state.add_state(window, self.TOMBSTONE, 1)
elif self.accumulation_mode == AccumulationMode.DISCARDING:
state.clear_state(window, self.ELEMENTS)
timestamp = state.get_state(window, self.WATERMARK_HOLD)
if timestamp is None:
# If no watermark hold was set, output at end of window.
timestamp = window.max_timestamp()
elif input_watermark < window.end and self.trigger_fn.has_ontime_pane():
# Hold the watermark in case there is an empty pane that needs to be fired
# at the end of the window.
pass
else:
state.clear_state(window, self.WATERMARK_HOLD)
return WindowedValue(values, timestamp, (window, ), pane_info)
def run():
print("Town of Squirreliwink Bureau Of Tolls and Nuts Affair\n\n[PART-4]")
# parse command line args:
# - parse both beam args and known script args
parser = argparse.ArgumentParser(
description="Town of Squirreliwink Bureau Of Tolls and Nuts Affair")
parser.add_argument('-i',
'--input',
type=str,
default='./data/input',
help='Input folder')
parser.add_argument('-o',
'--output',
type=str,
default='./data/output',
help='Output folder')
known_args, beam_args = parser.parse_known_args(sys.argv)
# delete previous run files
delete_files(os.path.join(known_args.output, "report*"))
# construct pipeline and run
options = PipelineOptions(beam_args)
with beam.Pipeline(options=options) as pipeline:
# create a pcollection of nut prices
logger.info("creating nut prices side input")
nut_prices = (pipeline
| beam.Create([('cornsilk', 2.0), ('slate_gray', 3.5),
('navajo_white', 7.0)]))
# read toll records and pass in nut prices as a side_input
# you can convert a (k, v) tuple pcollection into a {k: v} with beam.pvalue.AsDict()
logger.info("reading toll records")
records = (pipeline
| beam.io.ReadFromText(os.path.join(known_args.input,
'tollbooth_logs.csv'),
skip_header_lines=1)
| beam.Map(parse_csv)
| beam.ParDo(PrepareAndAddTotalsWithSideInput(),
nut_prices=beam.pvalue.AsDict(nut_prices)))
# multi-keys multi-values combiner by using beam.combiners.TupleCombineFn()
# first normalize rows into ((license_plate, month), (1, total, cornsilk, slate gray, navajo white, total)) tuple
# then apply a tuple of combiners over values
records = (records
| beam.Map(key_by_license_plate_month)
| beam.CombinePerKey(
beam.combiners.TupleCombineFn(combine.CountCombineFn(),
sum, sum, sum, sum,
combine.MeanCombineFn())))
# read squirreliwink population file
# file consist of newline delimited json rows. read each json row as dict
logger.info("reading Squirreliwink's residents file")
residents = (pipeline
| "residents" >> beam.io.ReadFromText(
os.path.join(known_args.input,
'squirreliwink_population.json'))
| beam.Map(lambda line: json.loads(line)))
# key residents by their license plate
logger.info("key residents by license_plate")
residents_by_plate = (
residents | beam.Map(lambda element: (element['car'], element)))
# lookup residents by their license plate using SideInputs
records = (
records
| beam.Map(
lambda e, lookup: (
# add family_name and address from resident lookup to the keys tuple.
# Remember e[0][0] (first value in the keys tuple) should contain our license_plate info
(e[0] + tuple(v for k, v in lookup[e[0][0]].items() if k in
('family_name', 'address'))),
e[1]),
lookup=beam.pvalue.AsDict(residents_by_plate)
) # pass in residents info as a SideInput
)
# (records | beam.Map(print))
# output to a newline delimited json file
logger.info("output record into csv file")
(records
| beam.Map(
lambda e: e[0] + e[1]
) # flatten ((keys), (values)) tuple into a single tuple (keys + values)
| beam.Map(lambda t: dict(
zip( # stitch up the results as a dict, adding back column names
('license_plate', 'month', 'family_name', 'address',
'visit_count', 'total', 'cornsilk', 'slate_gray',
'navajo_white', 'avg_total'), t)))
| beam.Map(lambda d: json.dumps(d, ensure_ascii=False)
) # json output the results
| beam.io.WriteToText(os.path.join(known_args.output, "report"),
file_name_suffix='.json'))
