Files
DocsGPT/application/cache.py
2024-10-12 15:25:06 -04:00

94 lines
3.3 KiB
Python

import sys
import redis
import time
from datetime import datetime
from application.core.settings import settings
from application.utils import get_hash
# Initialize Redis client
redis_client = redis.Redis(
host=settings.REDIS_HOST,
port=settings.REDIS_PORT,
db=settings.REDIS_DB,
)
def gen_cache_key(messages):
"""
Generate a unique cache key using the latest user prompt.
"""
latest_user_prompt = next((msg['content'] for msg in reversed(messages) if msg['role'] == 'user'), None)
if latest_user_prompt is None:
raise ValueError("No user message found in the conversation to generate a cache key.")
cache_key = get_hash(latest_user_prompt)
return cache_key
def gen_cache(func):
"""
Decorator to cache the response of a function that generates a response using an LLM.
This decorator first checks if a response is cached for the given input (model and messages).
If a cached response is found, it returns that. If not, it generates the response,
caches it, and returns the generated response.
Args:
func (function): The function to be decorated.
Returns:
function: The wrapped function that handles caching and LLM response generation.
"""
def wrapper(self, model, messages, *args, **kwargs):
cache_key = gen_cache_key(messages=messages)
cached_response = redis_client.get(cache_key)
if cached_response:
print(f"Cache hit for key: {cache_key}")
return cached_response.decode('utf-8')
result = func(self, model, messages, *args, **kwargs)
redis_client.set(cache_key, result, ex=3600)
print(f"Cache saved for key: {cache_key}")
return result
return wrapper
def stream_cache(func):
"""
Decorator to cache the streamed response of an LLM function.
This decorator first checks if a streamed response is cached for the given input (model and messages).
If a cached response is found, it yields that. If not, it streams the response, caches it,
and then yields the response.
Args:
func (function): The function to be decorated.
Returns:
function: The wrapped function that handles caching and streaming LLM responses.
"""
def wrapper(self, model, messages, *args, **kwargs):
cache_key = gen_cache_key(messages=messages)
# we are using lrange and rpush to simulate streaming
cached_response = redis_client.lrange(cache_key, 0, -1)
if cached_response:
print(f"Cache hit for stream key: {cache_key}")
for chunk in cached_response:
print(f"Streaming cached chunk: {chunk.decode('utf-8')}")
yield chunk.decode('utf-8')
# need to slow down the response to simulate streaming
# because the cached response is instantaneous
# and redis is using in-memory storage
time.sleep(0.07)
return
result = func(self, model, messages, *args, **kwargs)
for chunk in result:
print(f"Streaming live chunk: {chunk}")
redis_client.rpush(cache_key, chunk)
yield chunk
# expire the cache after 30 minutes
redis_client.expire(cache_key, 1800)
print(f"Stream cache saved for key: {cache_key}")
return wrapper