| #!/usr/bin/env python |
| # |
| # 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 is a mapper for use with hadoop streaming. See data_generator.DatabasePopulator |
| for more information on how this file is used. |
| ''' |
| |
| import os |
| import random |
| import sys |
| |
| # When running locally, the PYTHONPATH needed by impala-shell interferes with python |
| # through YARN. Specifically, when the data generator needs to import common.py, python |
| # looks at $IMPALA_HOME/tests/common and errors when it doesn't find what was asked for. |
| sys.path.insert(1, os.getcwd()) |
| |
| from data_generator_mapred_common import ( |
| deserialize, |
| estimate_rows_per_reducer, |
| MB_PER_REDUCER, |
| serialize) |
| |
| for line in sys.stdin: |
| table_data_generator = deserialize(line) |
| random.seed(table_data_generator.randomization_seed) |
| row_count = table_data_generator.row_count |
| rows_per_batch = estimate_rows_per_reducer(table_data_generator, MB_PER_REDUCER) |
| batch_idx = 0 |
| while row_count > 0: |
| table_data_generator.row_count = min(row_count, rows_per_batch) |
| table_data_generator.randomization_seed = int(random.random() * sys.maxint) |
| |
| # Generate input for the reducers. |
| print("%s\t%s\t%s" % (table_data_generator.table.name, batch_idx, |
| serialize(table_data_generator))) |
| |
| batch_idx += 1 |
| row_count -= rows_per_batch |