Concepts
Keys
Keys define the subject being rate limited, from a user or API key to a tenant or route.
A key is the identity Trypema limits. Good keys make your policy meaningful.
What a key usually represents
- a user id
- an API key
- an IP address
- a tenant id
- a route + subject combination such as
tenant_42:/search
Local keys
The local provider accepts plain string slices such as "user_123". That makes it easy to apply limiting anywhere inside one process.
Redis and hybrid keys
Redis-backed providers use RedisKey, a validated key type. It must:
- not be empty
- be at most 255 bytes
- not contain
:
Those rules keep the Redis key layout predictable because Trypema uses : as part of its internal namespacing.
How to choose a good key
Choose the identity you actually want to protect:
- limit a person:
user_id - limit a customer account:
tenant_id - limit a credential:
api_key_id - limit a hotspot route separately:
tenant_id:/expensive-endpoint
Practical advice
- Keep keys stable over time.
- Keep them narrow enough to protect the thing that matters.
- Avoid mixing different policy scopes into one key unless that is the policy you want.
The provider changes how state is stored, not what a key means.