Redis as cache for postgreSql nested data

I’m working on web app using nestJs/postgres/redis.
What is the best way (best data structure) to cache following postgres table (hierarchy) to Redis ?

space:

• name
• another attribute
• users (one2many)

folders:

• spaceId
• name
• users (one2many)

files:

• folderId
• spaceId
• name
• users (one2many).

I already tried to cache this using key-value where the key is hashed from request and value is response of say getAllMyFiles but there will be some problem
Say i want to cache The route:

/my-files

key: users:[USER_ID]:documents:[QUERY-HASH]

the problem is that:

• i have to cache this for every user and thus the cache will get bigger
• when updating one file i have to invalidate the entire files-cache for all the users