TheAlanWang

Notes

05.Redis Deployment on docker

2 min read

docker run -d --name redis-local -p 6379:6379 redis:7

test redis

docker exec -it redis-local redis-cli
127.0.0.1:6379> PING
PONG
127.0.0.1:6379> SET hello world
OK
127.0.0.1:6379> GET hello
"world"

AOF (Append Only File)

OF (Append Only File) persists Redis data by logging write commands and replaying them on restart to rebuild the dataset.

docker rm -f redis-local # remove container
docker volume rm redis_data # remove data
docker run -d \
  --name redis-local \
  -p 6379:6379 \
  -v redis_data:/data \
  redis:7 \ # <image>
  redis-server --appendonly yes --requirepass "Password"

enter image, redis-cli

docker exec -it redis-local redis-cli -a "Password"

test AOF

# method 1: restart check valid
docker restart redis-local
docker exec -it redis-local redis-cli -a "Password" GET mykey
 
# method 2: delete container, test volum
docker rm -f redis-local
# recreate
docker run -d \
  --name redis-local \
  -p 6379:6379 \
  -v redis_data:/data \
  redis:7 \
  redis-server --appendonly yes --requirepass "Password"
 
docker exec -it redis-local redis-cli -a "Password" GET mykey

Fast API test

Install

python -m pip install fastapi uvicorn redis
  • -m means: “run a module using Python”
  • Redis (the server) is already running in Docker (redis:7 container).
  • Python dependencies so your FastAPI app can talk to Redis
source .venv/bin/activate
export REDIS_PASSWORD="Password"
python -m uvicorn main:app --reload --port 8000

TTL setting

ANSWER_TTL_SECONDS = int(os.getenv("ANSWER_TTL_SECONDS", "600"))
 
async def set_cached_answer(doc_id: str, question: str, answer: str) -> None:
    r = await get_redis()
    # TTL makes it "periodically deleted" automatically
    await r.set(_answer_key(doc_id, question), answer, ex=ANSWER_TTL_SECONDS)

Graph View