0x01-caching

Caching

The learning objectives of this project are:

• What a caching system is
• What FIFO means
• What LIFO means
• What LRU means
• What MRU means
• What LFU means
• What the purpose of a caching system
• What limits a caching system have

0. Basic dictionary

Create a class BasicCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• This caching system doesn’t have limit
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None.

1. FIFO caching

Create a class FIFOCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• You can overload def __init__(self): but don’t forget to call the parent init: super().__init__()
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
  • If the number of items in self.cache_data is higher that BaseCaching.MAX_ITEMS:
    • you must discard the first item put in cache (FIFO algorithm)
    • you must print DISCARD: with the key discarded and following by a new line
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None.

2. LIFO Caching

Create a class LIFOCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• You can overload def __init__(self): but don’t forget to call the parent init: super().__init__()
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
  • If the number of items in self.cache_data is higher that BaseCaching.MAX_ITEMS:
    • you must discard the last item put in cache (LIFO algorithm)
    • you must print DISCARD: with the key discarded and following by a new line
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None

3. LRU Caching

Create a class LRUCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• You can overload def __init__(self): but don’t forget to call the parent init: super().__init__()
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
  • If the number of items in self.cache_data is higher that BaseCaching.MAX_ITEMS:
    • you must discard the least recently used item (LRU algorithm)
    • you must print DISCARD: with the key discarded and following by a new line
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None

4. MRU Caching

Create a class MRUCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• You can overload def __init__(self): but don’t forget to call the parent init: super().__init__()
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
  • If the number of items in self.cache_data is higher that BaseCaching.MAX_ITEMS:
    • you must discard the most recently used item (MRU algorithm)
    • you must print DISCARD: with the key discarded and following by a new line
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None

100. LFU Caching

Create a class LFUCache that inherits from BaseCaching and is a caching system:

• You must use self.cache_data - dictionary from the parent class BaseCaching
• You can overload def __init__(self): but don’t forget to call the parent init: super().__init__()
• def put(self, key, item):
  • Must assign to the dictionary self.cache_data the item value for the key key.
  • If key or item is None, this method should not do anything.
  • If the number of items in self.cache_data is higher that BaseCaching.MAX_ITEMS:
    • you must discard the least frequency used item (LFU algorithm)
    • if you find more than 1 item to discard, you must use the LRU algorithm to discard only the least recently used
    • you must print DISCARD: with the key discarded and following by a new line
• def get(self, key):
  • Must return the value in self.cache_data linked to key.
  • If key is None or if the key doesn’t exist in self.cache_data, return None