lingfromSh / psychic-spoon

A tool for managing chaos cache keys.

Psychic Spoon

Introduction

Cache key management always is a tough task during developing.

Cache a data may involve generating keys, converting data to right struct, assigning expiration, converting raw to proper python type and handling failures.

The purpose of Psychic Spoon is to keep your plenty of cache keys clear.

Concepts

In KV databases, a key is used as the unique identification to access the value. In practice, keys with the same pattern are generally designed as a kind of data with the same structure. And Various KV databases almost are same.

Therefore, Psychic Spoon provides:

1. a key object to describe key's pattern and data structure.
2. a type object to describe data in python.
3. a backend object to describe how data in python to store in database.

Key

from psychic_spoon.key import Key

Type

• Boolean
• Dict (support nested)
• Float
• Integer
• List (support nested)
• Set (support nested)
• String

Backend

• RedisBackend
  • RedisStringBackend
  • RedisSetBackend

Usage

For example, we need a redis string to store a user's session dict.

from datetime import timedelta
from psychic_spoon.key import Key
from psychic_spoon.types.dict import Dict
from psychic_spoon.types.integer import Integer
from psychic_spoon.types.set import Set
from psychic_spoon.types.string import String
from psychic_spoon.backends.redis_backend import RedisStringBackend

backend = RedisStringBackend(host="localhost", port=6379)

user_session_cache = Key("user:{id}:session",
                         datatype=Dict(
                             username=String,
                             name=String,
                             age=Integer,
                             roles=Set(Integer),
                             ip_address=Dict(
                                 type=String,
                                 address=String
                             )
                         ),
                         backend=backend,
                         ttl=timedelta(hours=12))

key = user_session_cache.build_key(id=1)
user_dict = {
    "username": "jame-curtis",
    "name": "James Curtis",
    "age": 26,
    "roles": {15, 82, 81},
    "ip_address": {
        "type": "ipv4",
        "address": "192.168.1.1"
    }
}

# Save your cache
user_session_cache.set(key, user_dict)

# Fetch your cache
user_dict = user_session_cache.get(key)

Roadmap

• An event loop to handling success/failure callback
• Replace pottery with RedisBackend
• More support to redis model