StrictRedis() needs to be used when redis has a password

[rberlind]

I set a password on my redis database by adding command: ["redis-server"] and args = ["--requirepass " ] to the azure-vote-back container specification in my copy of azure-vote-all-in-one-redis.yml. I was able to validate with redis-cli AUTH on that container that the password was really set.

I also added the extra environment variable, REDIS_PWD, that was referenced in main.py in the azure-vote-front container and set it to the same password.

However, the azure-vote-front app could not connect to the redis database. It gave the error: "redis.exceptions.ResponseError: NOAUTH Authentication required."

But when I used kubectl exec cats-and-dogs-front -i -t -- bash to access the container and used apt-get update and apt-get install redis-tools and then used redis-cli against the correct host and port, I was able to connect. I was also able to run the AUTH command and authenticate. Additionally, I could see that REDIS_PWD was set with the correct password by running env | grep REDIS.

My conclusion was that the redis password was being set correctly both in the front and back apps and that I did not have a connectivity issue between the containers themselves (since redis-cli worked). So, I concluded that something must be wrong with the python code.

I researched the redis-py module being used and found docs at https://redis-py.readthedocs.io/en/latest/ which suggested that redis.Redis() is provided for backwards compatibility with older versions of redis-py and that redis.StrictRedis() is preferred.

So, I changed the code to use redis.StrictRedis instead of redis.Redis when the REDIS_PWD environment variable is set.

I built my own docker image at rberlind/azure-vote-front:redis-pwd and modified the yml file to use that image. Everything then worked.

I will submit a pull request.

[neilpeterson]

I've merged the PR - thanks again.