caching/_examples_/property_cache_json.py

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

import caching
import logging
import sys
import time


class test_slow_data(object):
    DATA_VERSION = 0.1
    KEY_ONE = '1'
    KEY_TWO = '2'
    KEY_THREE = 'three'
    KEY_FOUR = 'four'
    KEY_FIVE = 'five'
    KEYS = [KEY_ONE, KEY_TWO, KEY_THREE, KEY_FOUR, KEY_FIVE]

    def data_version(self):
        return self.DATA_VERSION

    def get(self, key, default=None):
        try:
            return getattr(self, f'__{key}__')()
        except AttributeError:
            return default

    def keys(self):
        return self.KEYS

    def uid(self):
        return None

    def print_n_sleep(self, k):
        sys.stdout.write('slow get executed for %s\n' % k)
        time.sleep(3)

    def __1__(self):
        self.print_n_sleep("__1__")
        return 'one'

    def __2__(self):
        self.print_n_sleep("__2__")
        return 'two'

    def __three__(self):
        self.print_n_sleep("__three__")
        return 'three'

    def __four__(self):
        self.print_n_sleep("__four__")
        return 'four'

    def __five__(self):
        self.print_n_sleep("__five__")
        return 'five'

class test_slow_data_cached(test_slow_data):
    def __init__(self, *args, **kwargs) -> None:
        super().__init__(*args, **kwargs)
        self._cache = caching.property_cache_json(test_slow_data(), 'cache.json')
        self._cache.add_source_get_keys(self.KEY_THREE)

    def get(self, key, default=None):
        return self._cache.get(key, default)


if __name__ == "__main__":
    # Logging configuration
    logging.basicConfig(
        format="%(asctime)s: %(levelname)8s - %(name)s - %(message)s",
        level=logging.DEBUG,
        stream=sys.stdout
    )
    # Example
    tm = time.time()
    data = test_slow_data_cached()
    print('Testing property_cache (json):\n--------------------------------')
    for key in data.keys():
        print(data.get(key))
    print('--------------------------------\nThe execution time was %.1fs' % (time.time()-tm))