| # 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 datetime import datetime, timedelta |
| from decimal import Decimal as PyDecimal |
| from random import randint, random, uniform |
| |
| from tests.comparison.db_types import Boolean, Char, Decimal, Float, Int, Timestamp |
| |
| class RandomValGenerator(object): |
| |
| def __init__(self, |
| min_number=-1000, |
| max_number=1000, |
| min_date=datetime(1990, 1, 1), |
| max_date=datetime(2030, 1, 1), |
| null_val_percentage=0.1): |
| if type(min_number) != int or type(max_number) != int: |
| raise Exception("min_number and max_number must be integers but were %s and %s" |
| % (type(min_number), type(max_number))) |
| self.min_number = min_number |
| self.max_number = max_number |
| self.min_date = min_date |
| self.max_date = max_date |
| self.null_val_percentage = null_val_percentage |
| |
| def generate_val(self, val_type): |
| '''Generate and return a single random val. Use the val_type parameter to |
| specify the type of val to generate. See types.py for valid val_type |
| options. |
| |
| Ex: |
| generator = RandomValGenerator(min_number=1, max_number=5) |
| val = generator.generate_val(model.Int) |
| assert 1 <= val and val <= 5 |
| ''' |
| return next(self.create_val_generator(val_type)) |
| |
| def create_val_generator(self, val_type): |
| '''Generate and return a single random val. Use the val_type parameter to |
| specify the type of val to generate. See types.py for valid val_type |
| options. |
| |
| Ex: |
| generator = RandomValGenerator(min_number=1, max_number=5) |
| val = generator.generate_val(model.Int) |
| assert 1 <= val and val <= 5 |
| ''' |
| if issubclass(val_type, Int): |
| def val(): |
| return randint( |
| max(self.min_number, val_type.MIN), min(val_type.MAX, self.max_number)) |
| elif issubclass(val_type, Char): |
| def val(): |
| val = randint( |
| max(self.min_number, val_type.MIN), min(val_type.MAX, self.max_number)) |
| return None if val is None else str(val)[:val_type.MAX] |
| elif issubclass(val_type, Decimal): |
| # Create an int within the maximum length of the Decimal, then shift the decimal |
| # point as needed. |
| max_digits = val_type.MAX_DIGITS |
| fractal_digits = val_type.MAX_FRACTIONAL_DIGITS |
| max_type_val = 10 ** max_digits |
| decimal_point_shift = 10 ** fractal_digits |
| max_val = min(self.max_number * decimal_point_shift, max_type_val - 1) |
| min_val = max(self.min_number * decimal_point_shift, -1 * max_type_val + 1) |
| def val(): |
| val = PyDecimal(randint(min_val, max_val)) |
| return val.scaleb(-1 * val_type.MAX_FRACTIONAL_DIGITS) |
| elif issubclass(val_type, Float): |
| def val(): |
| return uniform(self.min_number, self.max_number) |
| elif issubclass(val_type, Timestamp): |
| delta = self.max_date - self.min_date |
| delta_in_seconds = delta.days * 24 * 60 * 60 + delta.seconds |
| def val(): |
| offset_in_seconds = randint(0, delta_in_seconds) |
| val = self.min_date + timedelta(0, offset_in_seconds) |
| return datetime(val.year, val.month, val.day) |
| elif issubclass(val_type, Boolean): |
| def val(): |
| return randint(0, 1) == 1 |
| else: |
| raise Exception('Unsupported type %s' % val_type.__name__) |
| |
| while True: |
| if random() < self.null_val_percentage: |
| yield None |
| else: |
| yield val() |