Best practices to store user information in Redis - redis

Question

I'm building a simple web application where I need to store user information when logged in.
The information that I need to store is in json format like:
User:{'name': 'John', roles:[1,2,3]}
I was thinking in storing the information with a combination of user + {user_id} like:
User_1: {'name': 'John', roles=[1,2,3]}
I needed to know if this is a good practice (thinking in retrieving the information fast) or if there is another alternative.

Answer 1

Option 1:
Using key: value pair.
"User_1": "name: John, roles=[1,2,3]"
Time complexity: O(1).
[x] But after getting the data from Redis you have to parse it again.
Option 2:
Using separate keys for name and roles.
"User_1_name": "John",
"User_1_roles": [1,2,3]
Time complexity: O(1) per request. In total for your example case it's constant.
[x] Extra call for same user.
Option 3:
Using hash.
user_1: {
"name": "John",
"roles": [1, 2, 3]
}
Time complexity: O(N). Where N is the number of fields in hash. But for your example case it's constant.
In my opinion using a hash will be the best option.

Answer 2

I guess your question is about the key, not value.
It's good practice to save user with user+id key.
And if you have another identify attribute for your user(Email for example), you'll need to map all users to their email.
So each user will have these keys in Redis:
User_1: {'name': 'John', roles:[1,2,3], 'email': 'blabla#test.com'}
User_blabla#test.com_id: 1
When you needed to find user by email, you can get the user id by reading the User_blabla#test.com_id(which it's value is equal to user's id 1), then get the User_1.