| ################################################################################ |
| # Licensed to the Apache Software Foundation (ASF) under one |
| # or more contributor license agreements. See the NOTICE file |
| # distributed with this work for additional information |
| # regarding copyright ownership. The ASF licenses this file |
| # to you under the Apache License, Version 2.0 (the |
| # "License"); you may not use this file except in compliance |
| # with the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| ################################################################################ |
| from abc import ABC, abstractmethod |
| from typing import List, Dict, Iterable |
| |
| from pyflink.common import Row, RowKind |
| from pyflink.fn_execution.coders import PickleCoder |
| from pyflink.fn_execution.table.state_data_view import DataViewSpec, ListViewSpec, MapViewSpec, \ |
| PerKeyStateDataViewStore |
| from pyflink.table import AggregateFunction, FunctionContext, TableAggregateFunction |
| from pyflink.table.udf import ImperativeAggregateFunction |
| |
| |
| def join_row(left: List, right: List): |
| return Row(*(left + right)) |
| |
| |
| class DistinctViewDescriptor(object): |
| |
| def __init__(self, input_extractor, filter_args): |
| self._input_extractor = input_extractor |
| self._filter_args = filter_args |
| |
| def get_input_extractor(self): |
| return self._input_extractor |
| |
| def get_filter_args(self): |
| return self._filter_args |
| |
| |
| class RowKeySelector(object): |
| """ |
| A simple key selector used to extract the current key from the input List according to the |
| group-by field indexes. |
| """ |
| |
| def __init__(self, grouping): |
| self.grouping = grouping |
| |
| def get_key(self, data): |
| return [data[i] for i in self.grouping] |
| |
| |
| class AggsHandleFunctionBase(ABC): |
| """ |
| The base class for handling aggregate or table aggregate functions. |
| """ |
| |
| @abstractmethod |
| def open(self, state_data_view_store): |
| """ |
| Initialization method for the function. It is called before the actual working methods. |
| |
| :param state_data_view_store: The object used to manage the DataView. |
| """ |
| pass |
| |
| @abstractmethod |
| def accumulate(self, input_data: Row): |
| """ |
| Accumulates the input values to the accumulators. |
| |
| :param input_data: Input values bundled in a Row. |
| """ |
| pass |
| |
| @abstractmethod |
| def retract(self, input_data: Row): |
| """ |
| Retracts the input values from the accumulators. |
| |
| :param input_data: Input values bundled in a Row. |
| """ |
| |
| @abstractmethod |
| def merge(self, accumulators: List): |
| """ |
| Merges the other accumulators into current accumulators. |
| |
| :param accumulators: The other List of accumulators. |
| """ |
| pass |
| |
| @abstractmethod |
| def set_accumulators(self, accumulators: List): |
| """ |
| Set the current accumulators (saved in a List) which contains the current aggregated |
| results. |
| |
| In streaming: accumulators are stored in the state, we need to restore aggregate buffers |
| from state. |
| |
| In batch: accumulators are stored in the dict, we need to restore aggregate buffers from |
| dict. |
| |
| :param accumulators: Current accumulators. |
| """ |
| pass |
| |
| @abstractmethod |
| def get_accumulators(self) -> List: |
| """ |
| Gets the current accumulators (saved in a list) which contains the current |
| aggregated results. |
| |
| :return: The current accumulators. |
| """ |
| pass |
| |
| @abstractmethod |
| def create_accumulators(self) -> List: |
| """ |
| Initializes the accumulators and save them to an accumulators List. |
| |
| :return: A List of accumulators which contains the aggregated results. |
| """ |
| pass |
| |
| @abstractmethod |
| def cleanup(self): |
| """ |
| Cleanup for the retired accumulators state. |
| """ |
| pass |
| |
| @abstractmethod |
| def close(self): |
| """ |
| Tear-down method for this function. It can be used for clean up work. |
| By default, this method does nothing. |
| """ |
| pass |
| |
| |
| class AggsHandleFunction(AggsHandleFunctionBase): |
| """ |
| The base class for handling aggregate functions. |
| """ |
| |
| @abstractmethod |
| def get_value(self) -> List: |
| """ |
| Gets the result of the aggregation from the current accumulators. |
| |
| :return: The final result (saved in a row) of the current accumulators. |
| """ |
| pass |
| |
| |
| class TableAggsHandleFunction(AggsHandleFunctionBase): |
| """ |
| The base class for handling table aggregate functions. |
| """ |
| |
| @abstractmethod |
| def emit_value(self, current_key: List, is_retract: bool) -> Iterable[Row]: |
| """ |
| Emit the result of the table aggregation. |
| """ |
| pass |
| |
| |
| class SimpleAggsHandleFunctionBase(AggsHandleFunctionBase): |
| """ |
| A simple AggsHandleFunctionBase implementation which provides the basic functionality. |
| """ |
| |
| def __init__(self, |
| udfs: List[ImperativeAggregateFunction], |
| input_extractors: List, |
| udf_data_view_specs: List[List[DataViewSpec]], |
| filter_args: List[int], |
| distinct_indexes: List[int], |
| distinct_view_descriptors: Dict[int, DistinctViewDescriptor]): |
| self._udfs = udfs |
| self._input_extractors = input_extractors |
| self._accumulators: List = None |
| self._udf_data_view_specs = udf_data_view_specs |
| self._udf_data_views = [] |
| self._filter_args = filter_args |
| self._distinct_indexes = distinct_indexes |
| self._distinct_view_descriptors = distinct_view_descriptors |
| self._distinct_data_views = {} |
| |
| def open(self, state_data_view_store): |
| for udf in self._udfs: |
| udf.open(state_data_view_store.get_runtime_context()) |
| self._udf_data_views = [] |
| for data_view_specs in self._udf_data_view_specs: |
| data_views = {} |
| for data_view_spec in data_view_specs: |
| if isinstance(data_view_spec, ListViewSpec): |
| data_views[data_view_spec.field_index] = \ |
| state_data_view_store.get_state_list_view( |
| data_view_spec.state_id, |
| data_view_spec.element_coder) |
| elif isinstance(data_view_spec, MapViewSpec): |
| data_views[data_view_spec.field_index] = \ |
| state_data_view_store.get_state_map_view( |
| data_view_spec.state_id, |
| data_view_spec.key_coder, |
| data_view_spec.value_coder) |
| self._udf_data_views.append(data_views) |
| for key in self._distinct_view_descriptors.keys(): |
| self._distinct_data_views[key] = state_data_view_store.get_state_map_view( |
| "agg%ddistinct" % key, |
| PickleCoder(), |
| PickleCoder()) |
| |
| def accumulate(self, input_data: Row): |
| for i in range(len(self._udfs)): |
| if i in self._distinct_data_views: |
| if len(self._distinct_view_descriptors[i].get_filter_args()) == 0: |
| filtered = False |
| else: |
| filtered = True |
| for filter_arg in self._distinct_view_descriptors[i].get_filter_args(): |
| if input_data[filter_arg]: |
| filtered = False |
| break |
| if not filtered: |
| input_extractor = self._distinct_view_descriptors[i].get_input_extractor() |
| args = input_extractor(input_data) |
| if args in self._distinct_data_views[i]: |
| self._distinct_data_views[i][args] += 1 |
| else: |
| self._distinct_data_views[i][args] = 1 |
| if self._filter_args[i] >= 0 and not input_data[self._filter_args[i]]: |
| continue |
| input_extractor = self._input_extractors[i] |
| args = input_extractor(input_data) |
| if self._distinct_indexes[i] >= 0: |
| if args in self._distinct_data_views[self._distinct_indexes[i]]: |
| if self._distinct_data_views[self._distinct_indexes[i]][args] > 1: |
| continue |
| else: |
| raise Exception( |
| "The args are not in the distinct data view, this should not happen.") |
| self._udfs[i].accumulate(self._accumulators[i], *args) |
| |
| def retract(self, input_data: Row): |
| for i in range(len(self._udfs)): |
| if i in self._distinct_data_views: |
| if len(self._distinct_view_descriptors[i].get_filter_args()) == 0: |
| filtered = False |
| else: |
| filtered = True |
| for filter_arg in self._distinct_view_descriptors[i].get_filter_args(): |
| if input_data[filter_arg]: |
| filtered = False |
| break |
| if not filtered: |
| input_extractor = self._distinct_view_descriptors[i].get_input_extractor() |
| args = input_extractor(input_data) |
| if args in self._distinct_data_views[i]: |
| self._distinct_data_views[i][args] -= 1 |
| if self._distinct_data_views[i][args] == 0: |
| del self._distinct_data_views[i][args] |
| if self._filter_args[i] >= 0 and not input_data[self._filter_args[i]]: |
| continue |
| input_extractor = self._input_extractors[i] |
| args = input_extractor(input_data) |
| if self._distinct_indexes[i] >= 0 and \ |
| args in self._distinct_data_views[self._distinct_indexes[i]]: |
| continue |
| self._udfs[i].retract(self._accumulators[i], *args) |
| |
| def merge(self, accumulators: List): |
| for i in range(len(self._udfs)): |
| self._udfs[i].merge(self._accumulators[i], [accumulators[i]]) |
| |
| def set_accumulators(self, accumulators: List): |
| if self._udf_data_views: |
| for i in range(len(self._udf_data_views)): |
| for index, data_view in self._udf_data_views[i].items(): |
| accumulators[i][index] = data_view |
| self._accumulators = accumulators |
| |
| def get_accumulators(self): |
| return self._accumulators |
| |
| def create_accumulators(self): |
| return [udf.create_accumulator() for udf in self._udfs] |
| |
| def cleanup(self): |
| for i in range(len(self._udf_data_views)): |
| for data_view in self._udf_data_views[i].values(): |
| data_view.clear() |
| |
| def close(self): |
| for udf in self._udfs: |
| udf.close() |
| |
| |
| class SimpleAggsHandleFunction(SimpleAggsHandleFunctionBase, AggsHandleFunction): |
| """ |
| A simple AggsHandleFunction implementation which provides the basic functionality. |
| """ |
| |
| def __init__(self, |
| udfs: List[AggregateFunction], |
| input_extractors: List, |
| index_of_count_star: int, |
| count_star_inserted: bool, |
| udf_data_view_specs: List[List[DataViewSpec]], |
| filter_args: List[int], |
| distinct_indexes: List[int], |
| distinct_view_descriptors: Dict[int, DistinctViewDescriptor]): |
| super(SimpleAggsHandleFunction, self).__init__( |
| udfs, input_extractors, udf_data_view_specs, filter_args, distinct_indexes, |
| distinct_view_descriptors) |
| self._get_value_indexes = [i for i in range(len(udfs))] |
| if index_of_count_star >= 0 and count_star_inserted: |
| # The record count is used internally, should be ignored by the get_value method. |
| self._get_value_indexes.remove(index_of_count_star) |
| |
| def get_value(self): |
| return [self._udfs[i].get_value(self._accumulators[i]) for i in self._get_value_indexes] |
| |
| |
| class SimpleTableAggsHandleFunction(SimpleAggsHandleFunctionBase, TableAggsHandleFunction): |
| """ |
| A simple TableAggsHandleFunction implementation which provides the basic functionality. |
| """ |
| |
| def __init__(self, |
| udfs: List[TableAggregateFunction], |
| input_extractors: List, |
| udf_data_view_specs: List[List[DataViewSpec]], |
| filter_args: List[int], |
| distinct_indexes: List[int], |
| distinct_view_descriptors: Dict[int, DistinctViewDescriptor]): |
| super(SimpleTableAggsHandleFunction, self).__init__( |
| udfs, input_extractors, udf_data_view_specs, filter_args, distinct_indexes, |
| distinct_view_descriptors) |
| |
| def emit_value(self, current_key: List, is_retract: bool): |
| udf: TableAggregateFunction = self._udfs[0] |
| results = udf.emit_value(self._accumulators[0]) |
| for x in results: |
| result = join_row(current_key, self._convert_to_row(x)) |
| if is_retract: |
| result.set_row_kind(RowKind.DELETE) |
| else: |
| result.set_row_kind(RowKind.INSERT) |
| yield result |
| |
| def _convert_to_row(self, data): |
| if isinstance(data, Row): |
| return data._values |
| elif isinstance(data, tuple): |
| return list(data) |
| else: |
| return [data] |
| |
| |
| class RecordCounter(ABC): |
| """ |
| The RecordCounter is used to count the number of input records under the current key. |
| """ |
| |
| @abstractmethod |
| def record_count_is_zero(self, acc): |
| pass |
| |
| @staticmethod |
| def of(index_of_count_star): |
| if index_of_count_star >= 0: |
| return RetractionRecordCounter(index_of_count_star) |
| else: |
| return AccumulationRecordCounter() |
| |
| |
| class AccumulationRecordCounter(RecordCounter): |
| |
| def record_count_is_zero(self, acc): |
| # when all the inputs are accumulations, the count will never be zero |
| return acc is None |
| |
| |
| class RetractionRecordCounter(RecordCounter): |
| |
| def __init__(self, index_of_count_star): |
| self._index_of_count_star = index_of_count_star |
| |
| def record_count_is_zero(self, acc: List): |
| # We store the counter in the accumulator and the counter is never be null |
| return acc is None or acc[self._index_of_count_star][0] == 0 |
| |
| |
| class GroupAggFunctionBase(object): |
| |
| def __init__(self, |
| aggs_handle: AggsHandleFunctionBase, |
| key_selector: RowKeySelector, |
| state_backend, |
| state_value_coder, |
| generate_update_before: bool, |
| state_cleaning_enabled: bool, |
| index_of_count_star: int): |
| self.aggs_handle = aggs_handle |
| self.generate_update_before = generate_update_before |
| self.state_cleaning_enabled = state_cleaning_enabled |
| self.key_selector = key_selector |
| self.state_value_coder = state_value_coder |
| self.state_backend = state_backend |
| self.record_counter = RecordCounter.of(index_of_count_star) |
| self.buffer = {} |
| |
| def open(self, function_context: FunctionContext): |
| self.aggs_handle.open(PerKeyStateDataViewStore(function_context, self.state_backend)) |
| |
| def close(self): |
| self.aggs_handle.close() |
| |
| def process_element(self, input_data: Row): |
| input_value = input_data._values |
| key = self.key_selector.get_key(input_value) |
| try: |
| self.buffer[tuple(key)].append(input_data) |
| except KeyError: |
| self.buffer[tuple(key)] = [input_data] |
| |
| def on_timer(self, key: Row): |
| if self.state_cleaning_enabled: |
| self.state_backend.set_current_key(list(key._values)) |
| accumulator_state = self.state_backend.get_value_state( |
| "accumulators", self.state_value_coder) |
| accumulator_state.clear() |
| self.aggs_handle.cleanup() |
| |
| @abstractmethod |
| def finish_bundle(self): |
| pass |
| |
| |
| class GroupAggFunction(GroupAggFunctionBase): |
| |
| def __init__(self, |
| aggs_handle: AggsHandleFunction, |
| key_selector: RowKeySelector, |
| state_backend, |
| state_value_coder, |
| generate_update_before: bool, |
| state_cleaning_enabled: bool, |
| index_of_count_star: int): |
| super(GroupAggFunction, self).__init__( |
| aggs_handle, key_selector, state_backend, state_value_coder, generate_update_before, |
| state_cleaning_enabled, index_of_count_star) |
| |
| def finish_bundle(self): |
| for current_key, input_rows in self.buffer.items(): |
| current_key = list(current_key) |
| first_row = False |
| self.state_backend.set_current_key(current_key) |
| self.state_backend.clear_cached_iterators() |
| accumulator_state = self.state_backend.get_value_state( |
| "accumulators", self.state_value_coder) |
| accumulators: List = accumulator_state.value() |
| start_index = 0 |
| if accumulators is None: |
| for i in range(len(input_rows)): |
| if input_rows[i]._is_retract_msg(): |
| start_index += 1 |
| else: |
| break |
| if start_index == len(input_rows): |
| return |
| accumulators = self.aggs_handle.create_accumulators() |
| first_row = True |
| |
| # set accumulators to handler first |
| self.aggs_handle.set_accumulators(accumulators) |
| |
| # get previous aggregate result |
| pre_agg_value: List = self.aggs_handle.get_value() |
| |
| for input_row in input_rows[start_index:]: |
| # update aggregate result and set to the newRow |
| if input_row._is_accumulate_msg(): |
| # accumulate input |
| self.aggs_handle.accumulate(input_row) |
| else: |
| # retract input |
| self.aggs_handle.retract(input_row) |
| |
| # get current aggregate result |
| new_agg_value: List = self.aggs_handle.get_value() |
| |
| # get accumulator |
| accumulators = self.aggs_handle.get_accumulators() |
| |
| if not self.record_counter.record_count_is_zero(accumulators): |
| # we aggregated at least one record for this key |
| |
| # update the state |
| accumulator_state.update(accumulators) |
| |
| # if this was not the first row and we have to emit retractions |
| if not first_row: |
| if pre_agg_value != new_agg_value: |
| # retract previous result |
| if self.generate_update_before: |
| # prepare UPDATE_BEFORE message for previous row |
| retract_row = join_row(current_key, pre_agg_value) |
| retract_row.set_row_kind(RowKind.UPDATE_BEFORE) |
| yield retract_row |
| # prepare UPDATE_AFTER message for new row |
| result_row = join_row(current_key, new_agg_value) |
| result_row.set_row_kind(RowKind.UPDATE_AFTER) |
| yield result_row |
| else: |
| # this is the first, output new result |
| # prepare INSERT message for new row |
| result_row = join_row(current_key, new_agg_value) |
| result_row.set_row_kind(RowKind.INSERT) |
| yield result_row |
| else: |
| # we retracted the last record for this key |
| # sent out a delete message |
| if not first_row: |
| # prepare delete message for previous row |
| result_row = join_row(current_key, pre_agg_value) |
| result_row.set_row_kind(RowKind.DELETE) |
| yield result_row |
| # and clear all state |
| accumulator_state.clear() |
| # cleanup dataview under current key |
| self.aggs_handle.cleanup() |
| self.buffer = {} |
| |
| |
| class GroupTableAggFunction(GroupAggFunctionBase): |
| def __init__(self, |
| aggs_handle: TableAggsHandleFunction, |
| key_selector: RowKeySelector, |
| state_backend, |
| state_value_coder, |
| generate_update_before: bool, |
| state_cleaning_enabled: bool, |
| index_of_count_star: int): |
| super(GroupTableAggFunction, self).__init__( |
| aggs_handle, key_selector, state_backend, state_value_coder, generate_update_before, |
| state_cleaning_enabled, index_of_count_star) |
| |
| def finish_bundle(self): |
| for current_key, input_rows in self.buffer.items(): |
| current_key = list(current_key) |
| first_row = False |
| self.state_backend.set_current_key(current_key) |
| self.state_backend.clear_cached_iterators() |
| accumulator_state = self.state_backend.get_value_state( |
| "accumulators", self.state_value_coder) |
| accumulators = accumulator_state.value() |
| start_index = 0 |
| if accumulators is None: |
| for i in range(len(input_rows)): |
| if input_rows[i]._is_retract_msg(): |
| start_index += 1 |
| else: |
| break |
| if start_index == len(input_rows): |
| return |
| accumulators = self.aggs_handle.create_accumulators() |
| first_row = True |
| |
| # set accumulators to handler first |
| self.aggs_handle.set_accumulators(accumulators) |
| |
| if not first_row and self.generate_update_before: |
| yield from self.aggs_handle.emit_value(current_key, True) |
| |
| for input_row in input_rows[start_index:]: |
| # update aggregate result and set to the newRow |
| if input_row._is_accumulate_msg(): |
| # accumulate input |
| self.aggs_handle.accumulate(input_row) |
| else: |
| # retract input |
| self.aggs_handle.retract(input_row) |
| |
| # get accumulator |
| accumulators = self.aggs_handle.get_accumulators() |
| |
| if not self.record_counter.record_count_is_zero(accumulators): |
| yield from self.aggs_handle.emit_value(current_key, False) |
| accumulator_state.update(accumulators) |
| else: |
| # and clear all state |
| accumulator_state.clear() |
| # cleanup dataview under current key |
| self.aggs_handle.cleanup() |
| self.buffer = {} |
