Rate Limiter Implementation | Dataford Interview Questions

Implement the rate limiter implementations.

Use the supplied API request and policy data to calculate decisions for fixed-window, sliding-window, and token-bucket implementations. Return one result for every request covered by a policy.

Output

Columns: request_id, policy_id, request_ts, fixed_window_allowed, sliding_window_allowed, token_bucket_allowed
One row per request, with each decision represented as a boolean
Sort by request_id ascending

Schema

rate_limit_policies

Column	Type	Description
policy_idPK	INT	Unique rate limit policy identifier
endpoint	VARCHAR(100)	API endpoint covered by the policy
max_requests	INT	Maximum requests permitted in one fixed or sliding window
window_seconds	INT	Window duration in seconds
bucket_capacity	INT	Maximum number of tokens held by the bucket
refill_per_second	NUMERIC(8,4)	Tokens added per second

api_requests

Column	Type	Description
request_idPK	INT	Unique API request identifier
policy_id	INT	Applied rate limit policy
request_ts	TIMESTAMP	Timestamp when the request arrived
client_name	VARCHAR(100)	Logical client making the request
user_agent	VARCHAR(200)	Optional client user agent

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