[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386726726
 
 

 ##
 File path: sdks/python/apache_beam/runners/direct/transform_evaluator.py
 ##
 @@ -471,7 +517,14 @@ def process_element(self, element):
 # We can either have the _TestStream or the _WatermarkController to emit
 # the elements. We chose to emit in the _WatermarkController so that the
 # element is emitted at the correct watermark value.
-for event in self.test_stream.events(self.current_index):
+events = []
+if self.watermark == MIN_TIMESTAMP:
 
 Review comment:
   I added a comment that explains this loop and its idempotency.


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[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386726510
 
 

 ##
 File path: sdks/python/apache_beam/runners/direct/transform_evaluator.py
 ##
 @@ -471,7 +517,14 @@ def process_element(self, element):
 # We can either have the _TestStream or the _WatermarkController to emit
 # the elements. We chose to emit in the _WatermarkController so that the
 # element is emitted at the correct watermark value.
-for event in self.test_stream.events(self.current_index):
+events = []
+if self.watermark == MIN_TIMESTAMP:
 
 Review comment:
   Yep, this can be called more than once, and I verified that it's okay for it 
to be called multiple times.


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[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386723318
 
 

 ##
 File path: sdks/python/apache_beam/testing/test_stream.py
 ##
 @@ -314,3 +355,239 @@ def from_runner_api_parameter(ptransform, payload, 
context):
 coder=coder,
 events=[Event.from_runner_api(e, coder) for e in payload.events],
 output_tags=output_tags)
+
+
+class TimingInfo(object):
+  def __init__(self, processing_time, watermark):
+self._processing_time = timestamp.Timestamp.of(processing_time)
+self._watermark = timestamp.Timestamp.of(watermark)
+
+  @property
+  def processing_time(self):
+return self._processing_time
+
+  @property
+  def watermark(self):
+return self._watermark
+
+  def __repr__(self):
+return '({}, {}, {})'.format(
+self.event_timestamp, self.processing_time, self.watermark)
+
+
+class PairWithTiming(PTransform):
+  """Pairs the input element with timing information.
+
+  Input: element; output: KV(element, timing information)
+  Where timing information := (processing time, watermark)
+
+  This is used in the ReverseTestStream implementation to replay watermark
+  advancements.
+  """
+
+  URN = "beam:transform:pair_with_timing:v1"
+
+  def expand(self, pcoll):
+return pvalue.PCollection.from_(pcoll)
+
+
+class ReverseTestStream(PTransform):
+  """A Transform that can create TestStream events from a stream of elements.
+
+  This currently assumes that this the pipeline being run on a single machine
+  and elements come in order and are outputted in the same order that they came
+  in.
+  """
+  class Format(Enum):
+TEST_STREAM_EVENTS = 1
+TEST_STREAM_FILE_RECORDS = 2
+SERIALIZED_TEST_STREAM_FILE_RECORDS = 3
+
+  def __init__(
+  self, sample_resolution_sec, output_tag, coder=None, output_format=None):
+self._sample_resolution_sec = sample_resolution_sec
+self._output_tag = output_tag
+self._output_format = output_format if output_format \
+  else ReverseTestStream.Format.TEST_STREAM_EVENTS
+self._coder = coder if coder else beam.coders.FastPrimitivesCoder()
+
+  def expand(self, pcoll):
+generator = (
+_TestStreamFileRecordGenerator(coder=self._coder) if (
+self._output_format in (
+self.Format.TEST_STREAM_FILE_RECORDS,
+self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS)) else
+_TestStreamEventGenerator())
+
+ret = (
+pcoll
+| beam.WindowInto(beam.window.GlobalWindows())
+
+# First get the initial timing information. This will be used to start
+# the periodic timers which will generate processing time and watermark
+# advancements every `sample_resolution_sec`.
+| 'initial timing' >> PairWithTiming()
+
+# Next, map every element to the same key so that only a single timer 
is
+# started for this given ReverseTestStream.
+| beam.Map(lambda x: (0, x))
+
+# Next, pass-through each element which will be paired with its timing
+# info in the next step. Also, start the periodic timers. We use timers
+# in this situation to capture watermark advancements that occur when
+# there are no elements being produced upstream.
+| beam.ParDo(
+_WatermarkEventGenerator(
+output_tag=self._output_tag,
+sample_resolution_sec=self._sample_resolution_sec))
+
+# Next, retrieve the timing information for watermark events that were
+# generated in the previous step. This is because elements generated
+# through the timers don't have their timing information yet.
+| 'timing info for watermarks' >> PairWithTiming()
+
+# Format the events properly.
+| beam.ParDo(generator))
+
+if self._output_format == self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS:
+
+  def serializer(e):
+return e.SerializeToString()
+
+  ret = ret | 'serializer' >> beam.Map(serializer)
+
+return ret
+
+
+class _WatermarkEventGenerator(beam.DoFn):
+  # Used to return the initial timing information.
+  EXECUTE_ONCE_STATE = beam.transforms.userstate.BagStateSpec(
+  name='execute_once_state', coder=beam.coders.FastPrimitivesCoder())
+  WATERMARK_TRACKER = TimerSpec('watermark_tracker', TimeDomain.REAL_TIME)
+
+  def __init__(self, output_tag, sample_resolution_sec=0.1):
+self._output_tag = output_tag
+self._sample_resolution_sec = sample_resolution_sec
+
+  @on_timer(WATERMARK_TRACKER)
+  def on_watermark_tracker(
+  self,
+  timestamp=beam.DoFn.TimestampParam,
+  window=beam.DoFn.WindowParam,
+  watermark_tracker=beam.DoFn.TimerParam(WATERMARK_TRACKER)):
+next_sample_time = (timestamp.micros * 1e-6) + self._sample_resolution_sec
+watermark_tracker.set(next_sample_time)
 
 Review comment:
   Added state in the _TestStr

[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386723371
 
 

 ##
 File path: sdks/python/apache_beam/testing/test_stream.py
 ##
 @@ -314,3 +355,239 @@ def from_runner_api_parameter(ptransform, payload, 
context):
 coder=coder,
 events=[Event.from_runner_api(e, coder) for e in payload.events],
 output_tags=output_tags)
+
+
+class TimingInfo(object):
+  def __init__(self, processing_time, watermark):
+self._processing_time = timestamp.Timestamp.of(processing_time)
+self._watermark = timestamp.Timestamp.of(watermark)
+
+  @property
+  def processing_time(self):
+return self._processing_time
+
+  @property
+  def watermark(self):
+return self._watermark
+
+  def __repr__(self):
+return '({}, {}, {})'.format(
+self.event_timestamp, self.processing_time, self.watermark)
+
+
+class PairWithTiming(PTransform):
+  """Pairs the input element with timing information.
+
+  Input: element; output: KV(element, timing information)
+  Where timing information := (processing time, watermark)
+
+  This is used in the ReverseTestStream implementation to replay watermark
+  advancements.
+  """
+
+  URN = "beam:transform:pair_with_timing:v1"
+
+  def expand(self, pcoll):
+return pvalue.PCollection.from_(pcoll)
+
+
+class ReverseTestStream(PTransform):
+  """A Transform that can create TestStream events from a stream of elements.
+
+  This currently assumes that this the pipeline being run on a single machine
+  and elements come in order and are outputted in the same order that they came
+  in.
+  """
+  class Format(Enum):
+TEST_STREAM_EVENTS = 1
+TEST_STREAM_FILE_RECORDS = 2
+SERIALIZED_TEST_STREAM_FILE_RECORDS = 3
+
+  def __init__(
+  self, sample_resolution_sec, output_tag, coder=None, output_format=None):
+self._sample_resolution_sec = sample_resolution_sec
+self._output_tag = output_tag
+self._output_format = output_format if output_format \
+  else ReverseTestStream.Format.TEST_STREAM_EVENTS
+self._coder = coder if coder else beam.coders.FastPrimitivesCoder()
+
+  def expand(self, pcoll):
+generator = (
+_TestStreamFileRecordGenerator(coder=self._coder) if (
+self._output_format in (
+self.Format.TEST_STREAM_FILE_RECORDS,
+self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS)) else
+_TestStreamEventGenerator())
+
+ret = (
+pcoll
+| beam.WindowInto(beam.window.GlobalWindows())
+
+# First get the initial timing information. This will be used to start
+# the periodic timers which will generate processing time and watermark
+# advancements every `sample_resolution_sec`.
+| 'initial timing' >> PairWithTiming()
+
+# Next, map every element to the same key so that only a single timer 
is
+# started for this given ReverseTestStream.
+| beam.Map(lambda x: (0, x))
+
+# Next, pass-through each element which will be paired with its timing
+# info in the next step. Also, start the periodic timers. We use timers
+# in this situation to capture watermark advancements that occur when
+# there are no elements being produced upstream.
+| beam.ParDo(
+_WatermarkEventGenerator(
+output_tag=self._output_tag,
+sample_resolution_sec=self._sample_resolution_sec))
+
+# Next, retrieve the timing information for watermark events that were
+# generated in the previous step. This is because elements generated
+# through the timers don't have their timing information yet.
+| 'timing info for watermarks' >> PairWithTiming()
+
+# Format the events properly.
+| beam.ParDo(generator))
+
+if self._output_format == self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS:
+
+  def serializer(e):
+return e.SerializeToString()
+
+  ret = ret | 'serializer' >> beam.Map(serializer)
+
+return ret
+
+
+class _WatermarkEventGenerator(beam.DoFn):
+  # Used to return the initial timing information.
+  EXECUTE_ONCE_STATE = beam.transforms.userstate.BagStateSpec(
+  name='execute_once_state', coder=beam.coders.FastPrimitivesCoder())
+  WATERMARK_TRACKER = TimerSpec('watermark_tracker', TimeDomain.REAL_TIME)
+
+  def __init__(self, output_tag, sample_resolution_sec=0.1):
+self._output_tag = output_tag
+self._sample_resolution_sec = sample_resolution_sec
+
+  @on_timer(WATERMARK_TRACKER)
+  def on_watermark_tracker(
+  self,
+  timestamp=beam.DoFn.TimestampParam,
+  window=beam.DoFn.WindowParam,
+  watermark_tracker=beam.DoFn.TimerParam(WATERMARK_TRACKER)):
+next_sample_time = (timestamp.micros * 1e-6) + self._sample_resolution_sec
+watermark_tracker.set(next_sample_time)
+
+# Generate two events, the delta since the

[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386711043
 
 

 ##
 File path: sdks/python/apache_beam/testing/test_stream.py
 ##
 @@ -314,3 +355,239 @@ def from_runner_api_parameter(ptransform, payload, 
context):
 coder=coder,
 events=[Event.from_runner_api(e, coder) for e in payload.events],
 output_tags=output_tags)
+
+
+class TimingInfo(object):
+  def __init__(self, processing_time, watermark):
+self._processing_time = timestamp.Timestamp.of(processing_time)
+self._watermark = timestamp.Timestamp.of(watermark)
+
+  @property
+  def processing_time(self):
+return self._processing_time
+
+  @property
+  def watermark(self):
+return self._watermark
+
+  def __repr__(self):
+return '({}, {}, {})'.format(
+self.event_timestamp, self.processing_time, self.watermark)
+
+
+class PairWithTiming(PTransform):
+  """Pairs the input element with timing information.
+
+  Input: element; output: KV(element, timing information)
+  Where timing information := (processing time, watermark)
+
+  This is used in the ReverseTestStream implementation to replay watermark
+  advancements.
+  """
+
+  URN = "beam:transform:pair_with_timing:v1"
+
+  def expand(self, pcoll):
+return pvalue.PCollection.from_(pcoll)
+
+
+class ReverseTestStream(PTransform):
+  """A Transform that can create TestStream events from a stream of elements.
+
+  This currently assumes that this the pipeline being run on a single machine
+  and elements come in order and are outputted in the same order that they came
+  in.
+  """
+  class Format(Enum):
+TEST_STREAM_EVENTS = 1
+TEST_STREAM_FILE_RECORDS = 2
+SERIALIZED_TEST_STREAM_FILE_RECORDS = 3
+
+  def __init__(
+  self, sample_resolution_sec, output_tag, coder=None, output_format=None):
+self._sample_resolution_sec = sample_resolution_sec
+self._output_tag = output_tag
+self._output_format = output_format if output_format \
+  else ReverseTestStream.Format.TEST_STREAM_EVENTS
+self._coder = coder if coder else beam.coders.FastPrimitivesCoder()
+
+  def expand(self, pcoll):
+generator = (
+_TestStreamFileRecordGenerator(coder=self._coder) if (
+self._output_format in (
+self.Format.TEST_STREAM_FILE_RECORDS,
+self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS)) else
+_TestStreamEventGenerator())
+
+ret = (
+pcoll
+| beam.WindowInto(beam.window.GlobalWindows())
+
+# First get the initial timing information. This will be used to start
+# the periodic timers which will generate processing time and watermark
+# advancements every `sample_resolution_sec`.
+| 'initial timing' >> PairWithTiming()
+
+# Next, map every element to the same key so that only a single timer 
is
+# started for this given ReverseTestStream.
+| beam.Map(lambda x: (0, x))
+
+# Next, pass-through each element which will be paired with its timing
+# info in the next step. Also, start the periodic timers. We use timers
+# in this situation to capture watermark advancements that occur when
+# there are no elements being produced upstream.
+| beam.ParDo(
+_WatermarkEventGenerator(
+output_tag=self._output_tag,
+sample_resolution_sec=self._sample_resolution_sec))
+
+# Next, retrieve the timing information for watermark events that were
+# generated in the previous step. This is because elements generated
+# through the timers don't have their timing information yet.
+| 'timing info for watermarks' >> PairWithTiming()
+
+# Format the events properly.
+| beam.ParDo(generator))
+
+if self._output_format == self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS:
+
+  def serializer(e):
+return e.SerializeToString()
+
+  ret = ret | 'serializer' >> beam.Map(serializer)
+
+return ret
+
+
+class _WatermarkEventGenerator(beam.DoFn):
+  # Used to return the initial timing information.
+  EXECUTE_ONCE_STATE = beam.transforms.userstate.BagStateSpec(
+  name='execute_once_state', coder=beam.coders.FastPrimitivesCoder())
+  WATERMARK_TRACKER = TimerSpec('watermark_tracker', TimeDomain.REAL_TIME)
+
+  def __init__(self, output_tag, sample_resolution_sec=0.1):
+self._output_tag = output_tag
+self._sample_resolution_sec = sample_resolution_sec
+
+  @on_timer(WATERMARK_TRACKER)
+  def on_watermark_tracker(
+  self,
+  timestamp=beam.DoFn.TimestampParam,
+  window=beam.DoFn.WindowParam,
+  watermark_tracker=beam.DoFn.TimerParam(WATERMARK_TRACKER)):
+next_sample_time = (timestamp.micros * 1e-6) + self._sample_resolution_sec
+watermark_tracker.set(next_sample_time)
+
+# Generate two events, the delta since the

[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386694935
 
 

 ##
 File path: sdks/python/apache_beam/runners/direct/transform_evaluator.py
 ##
 @@ -421,8 +424,12 @@ def process_element(self, element):
   main_output = list(self._outputs)[0]
   bundle = self._evaluation_context.create_bundle(main_output)
   for tv in event.timestamped_values:
-bundle.output(
-GlobalWindows.windowed_value(tv.value, timestamp=tv.timestamp))
+# Unreify the value into the correct window.
+try:
+  bundle.output(WindowedValue(**tv.value))
+except TypeError:
+  bundle.output(
+  GlobalWindows.windowed_value(tv.value, timestamp=tv.timestamp))
 
 Review comment:
   Added a test for this


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[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386694347
 
 

 ##
 File path: sdks/python/apache_beam/runners/direct/transform_evaluator.py
 ##
 @@ -432,6 +439,45 @@ def finish_bundle(self):
 self, self.bundles, [], None, {None: self._watermark})
 
 
+class PairWithTimingEvaluator(_TransformEvaluator):
+  """TransformEvaluator for the PairWithTiming transform.
+
+  This transform takes an element as an input and outputs
+  KV(element, `TimingInfo`). Where the `TimingInfo` contains both the
+  processing time timestamp and watermark.
+  """
+  def __init__(
+  self,
+  evaluation_context,
+  applied_ptransform,
+  input_committed_bundle,
+  side_inputs):
+assert not side_inputs
+super(PairWithTimingEvaluator, self).__init__(
+evaluation_context,
+applied_ptransform,
+input_committed_bundle,
+side_inputs)
+
+  def start_bundle(self):
+main_output = list(self._outputs)[0]
+self.bundle = self._evaluation_context.create_bundle(main_output)
+
+  def process_element(self, element):
+watermark_manager = self._evaluation_context._watermark_manager
+watermarks = watermark_manager.get_watermarks(self._applied_ptransform)
 
 Review comment:
   Done, moved to start_bundle


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[GitHub] [beam] rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the ReverseTestStream

2020-03-02 Thread GitBox
rohdesamuel commented on a change in pull request #10497: [BEAM-8335] Add the 
ReverseTestStream
URL: https://github.com/apache/beam/pull/10497#discussion_r386693162
 
 

 ##
 File path: sdks/python/apache_beam/testing/test_stream.py
 ##
 @@ -314,3 +355,239 @@ def from_runner_api_parameter(ptransform, payload, 
context):
 coder=coder,
 events=[Event.from_runner_api(e, coder) for e in payload.events],
 output_tags=output_tags)
+
+
+class TimingInfo(object):
+  def __init__(self, processing_time, watermark):
+self._processing_time = timestamp.Timestamp.of(processing_time)
+self._watermark = timestamp.Timestamp.of(watermark)
+
+  @property
+  def processing_time(self):
+return self._processing_time
+
+  @property
+  def watermark(self):
+return self._watermark
+
+  def __repr__(self):
+return '({}, {}, {})'.format(
+self.event_timestamp, self.processing_time, self.watermark)
+
+
+class PairWithTiming(PTransform):
+  """Pairs the input element with timing information.
+
+  Input: element; output: KV(element, timing information)
+  Where timing information := (processing time, watermark)
+
+  This is used in the ReverseTestStream implementation to replay watermark
+  advancements.
+  """
+
+  URN = "beam:transform:pair_with_timing:v1"
+
+  def expand(self, pcoll):
+return pvalue.PCollection.from_(pcoll)
+
+
+class ReverseTestStream(PTransform):
+  """A Transform that can create TestStream events from a stream of elements.
+
+  This currently assumes that this the pipeline being run on a single machine
+  and elements come in order and are outputted in the same order that they came
+  in.
+  """
+  class Format(Enum):
+TEST_STREAM_EVENTS = 1
+TEST_STREAM_FILE_RECORDS = 2
+SERIALIZED_TEST_STREAM_FILE_RECORDS = 3
+
+  def __init__(
+  self, sample_resolution_sec, output_tag, coder=None, output_format=None):
+self._sample_resolution_sec = sample_resolution_sec
+self._output_tag = output_tag
+self._output_format = output_format if output_format \
+  else ReverseTestStream.Format.TEST_STREAM_EVENTS
+self._coder = coder if coder else beam.coders.FastPrimitivesCoder()
+
+  def expand(self, pcoll):
+generator = (
+_TestStreamFileRecordGenerator(coder=self._coder) if (
+self._output_format in (
+self.Format.TEST_STREAM_FILE_RECORDS,
+self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS)) else
+_TestStreamEventGenerator())
+
+ret = (
+pcoll
+| beam.WindowInto(beam.window.GlobalWindows())
+
+# First get the initial timing information. This will be used to start
+# the periodic timers which will generate processing time and watermark
+# advancements every `sample_resolution_sec`.
+| 'initial timing' >> PairWithTiming()
+
+# Next, map every element to the same key so that only a single timer 
is
+# started for this given ReverseTestStream.
+| beam.Map(lambda x: (0, x))
+
+# Next, pass-through each element which will be paired with its timing
+# info in the next step. Also, start the periodic timers. We use timers
+# in this situation to capture watermark advancements that occur when
+# there are no elements being produced upstream.
+| beam.ParDo(
+_WatermarkEventGenerator(
+output_tag=self._output_tag,
+sample_resolution_sec=self._sample_resolution_sec))
+
+# Next, retrieve the timing information for watermark events that were
+# generated in the previous step. This is because elements generated
+# through the timers don't have their timing information yet.
+| 'timing info for watermarks' >> PairWithTiming()
+
+# Format the events properly.
+| beam.ParDo(generator))
+
+if self._output_format == self.Format.SERIALIZED_TEST_STREAM_FILE_RECORDS:
+
+  def serializer(e):
+return e.SerializeToString()
+
+  ret = ret | 'serializer' >> beam.Map(serializer)
+
+return ret
+
+
+class _WatermarkEventGenerator(beam.DoFn):
+  # Used to return the initial timing information.
+  EXECUTE_ONCE_STATE = beam.transforms.userstate.BagStateSpec(
+  name='execute_once_state', coder=beam.coders.FastPrimitivesCoder())
+  WATERMARK_TRACKER = TimerSpec('watermark_tracker', TimeDomain.REAL_TIME)
+
+  def __init__(self, output_tag, sample_resolution_sec=0.1):
+self._output_tag = output_tag
+self._sample_resolution_sec = sample_resolution_sec
+
+  @on_timer(WATERMARK_TRACKER)
+  def on_watermark_tracker(
+  self,
+  timestamp=beam.DoFn.TimestampParam,
+  window=beam.DoFn.WindowParam,
+  watermark_tracker=beam.DoFn.TimerParam(WATERMARK_TRACKER)):
+next_sample_time = (timestamp.micros * 1e-6) + self._sample_resolution_sec
+watermark_tracker.set(next_sample_time)
+
+# Generate two events, the delta since the