itodotimothy6 commented on code in PR #30734: URL: https://github.com/apache/beam/pull/30734#discussion_r1566240502
########## sdks/python/apache_beam/yaml/yaml_join.py: ########## @@ -0,0 +1,273 @@ +# +# 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. +# + +"""This module defines the Join operation.""" +from typing import Any +from typing import Dict +from typing import List +from typing import Optional +from typing import Union + +import apache_beam as beam +from apache_beam.yaml import yaml_provider + + +def _validate_input(pcolls): + error_prefix = f'Invalid input {pcolls} specified.' + if not isinstance(pcolls, dict): + raise ValueError(f'{error_prefix} It must be a dict.') + if len(pcolls) < 2: + raise ValueError( + f'{error_prefix} There should be at least 2 inputs to join.') + + +def _validate_type(type): + error_prefix = f'Invalid value "{type}" for "type". It should be' + if not isinstance(type, dict) and not isinstance(type, str): + raise ValueError(f'{error_prefix} a dict or a str.') + if isinstance(type, dict): Review Comment: Added a check for inner list. Thanks ########## sdks/python/apache_beam/yaml/yaml_join.py: ########## @@ -0,0 +1,273 @@ +# +# 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. +# + +"""This module defines the Join operation.""" +from typing import Any +from typing import Dict +from typing import List +from typing import Optional +from typing import Union + +import apache_beam as beam +from apache_beam.yaml import yaml_provider + + +def _validate_input(pcolls): + error_prefix = f'Invalid input {pcolls} specified.' + if not isinstance(pcolls, dict): + raise ValueError(f'{error_prefix} It must be a dict.') + if len(pcolls) < 2: + raise ValueError( + f'{error_prefix} There should be at least 2 inputs to join.') + + +def _validate_type(type): + error_prefix = f'Invalid value "{type}" for "type". It should be' + if not isinstance(type, dict) and not isinstance(type, str): + raise ValueError(f'{error_prefix} a dict or a str.') + if isinstance(type, dict): + error = ValueError( + f'{error_prefix} a dictionary of type [str, list[str]] ' + f'and have only one element with the key "outer".') + if len(type) != 1: + raise error + if next(iter(type)) != 'outer': + raise error + if not isinstance(type['outer'], list): + raise error + if isinstance(type, str) and type not in ('inner', 'outer', 'left', 'right'): + raise ValueError( + f'{error_prefix} ' + f'one of the following: "inner", "outer", "left", "right"') + + +def _validate_equalities(equalities, pcolls): + error_prefix = f'Invalid value "{equalities}" for "equalities".' + + valid_cols = {} + inputs = list(pcolls.keys()) + for input in inputs: + fields = set() + for field in pcolls[input].element_type._fields: + fields.add(field[0]) + valid_cols[input] = fields + + if isinstance(equalities, str): + for input in valid_cols.keys(): + if equalities not in valid_cols[input]: + raise ValueError( + f'{error_prefix} When "equalities" is a str, ' + f'it must be a field name that exists in all the specified inputs.') + equality = {input: equalities for input in inputs} + return [equality] + + if not isinstance(equalities, list): + raise ValueError(f'{error_prefix} It should be a str or a list.') + + input_edge_list = [] + for equality in equalities: + invalid_dict_error = ValueError( + f'{error_prefix} {equality} ' + f'should be a dict[str, str] containing at least 2 items.') + if not isinstance(equality, dict): + raise invalid_dict_error + if len(equality) < 2: + raise invalid_dict_error + + for input, col in equality.items(): + if input not in inputs: + raise ValueError( + f'{error_prefix} "{input}" is not a specified alias in "input"') + if col not in valid_cols[input]: + raise ValueError( + f'{error_prefix} "{col}" is not a valid field in "{input}"') + + input_edge_list.append(tuple(equality.keys())) + + if not _is_connected(input_edge_list): + raise ValueError( + f'{error_prefix} ' + f'The equalities provided does not ensure that ' + f'all the inputs {inputs} are connected.') + + return equalities + + +def _parse_fields(tables, fields): + output_fields = [] + named_columns = set() + for input, cols in fields.items(): + error_prefix = f'Invalid input "{input}" for fields.' + if input not in tables: + raise ValueError(error_prefix) + if isinstance(cols, list): + for col in cols: + if col in named_columns: + raise ValueError( + f'{error_prefix} ', + f'Same field name "{col}" was specified more than once.') + output_fields.append(f'{input}.{col} AS {col}') + named_columns.add(col) + elif isinstance(cols, dict): + for k, v in cols.items(): + if k in named_columns: + raise ValueError( + f'{error_prefix} ', + f'Same field name "{k}" was specified more than once.') + output_fields.append(f'{input}.{v} AS {k}') + named_columns.add(k) + else: + raise ValueError(error_prefix) + for table in tables: + if table not in fields.keys(): + output_fields.append(f'{table}.*') + return output_fields + + +def _is_connected(edge_list): + graph = {} + for edge in edge_list: + u, v = edge + if u not in graph: + graph[u] = [] + if v not in graph: + graph[v] = [] + graph[u].append(v) + graph[v].append(u) + + visited = set() + stack = [next(iter(graph))] + while stack: + node = stack.pop() + visited.add(node) + for neighbor in graph[node]: + if neighbor not in visited: + stack.append(neighbor) + + return len(visited) == len(graph) + + [email protected]_fn +def _SqlJoinTransform( + pcolls, + sql_transform_constructor, + type: Union[str, Dict[str, List]], + equalities: Union[str, List[Dict[str, str]]], + fields: Optional[Dict[str, Any]] = None): + """Joins two or more inputs using a specfied condition. + + Args: + type: The type of join. Could be a string value in + ["inner", "left", "right", "outer"] that specifies the type of join to + be performed. For scenarios with multiple inputs to join where different + join types are desired, specify the inputs to be outer joined. For + example, {outer: [input1, input2]} means that input1 & input2 will be + outer joined using the conditions specified, while other inputs will be + inner joined. + equalities: The condition to join on. A list of sets of columns that should + be equal to fulfill the join condition. For the simple scenario to join + on the same column across all inputs and the column name is the same, + specify the column name as a str. + fields: The fields to be outputted. A mapping with the input alias as the + key and the fields in the input to be outputted. The value in the map + can either be a dictionary with the new field name as the key and the + original field name as the value (e.g new_field_name: field_name), or a + list of the fields to be outputted with their original names + (e.g [col1, col2, col3]), or an '*' indicating all fields in the input + will be outputted. If not specified, all fields from all inputs will be + outputted. + """ + + _validate_input(pcolls) + _validate_type(type) + validate_equalities = _validate_equalities(equalities, pcolls) + Review Comment: fields validation is done in `_parse_fields()` It ensures fields, if specified, is in the above format -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
