Thread-Safe Rate Limiter for APIs | Dataford Interview Questions

Write a thread-safe rate limiter in Python or Go that handles high-throughput API requests from Zipline's global logistics partners.

Implement rate_limit_requests(requests, capacity, window_seconds). Each request is [partner_id, timestamp]. Return a Boolean for every request, allowing at most capacity accepted requests from each partner during any rolling window_seconds interval. Timestamps for each partner are nondecreasing. Protect shared state with a thread synchronization primitive.

Example: [["A", 0], ["A", 1], ["A", 2]], capacity 2, window 10 returns [true, true, false]. At timestamp 10, timestamp 0 has expired.

Constraints: 1 <= capacity <= 10^5, 1 <= window_seconds <= 10^9, and at most 1000 requests per call.

Constraints

1 <= capacity <= 10^5
1 <= window_seconds <= 10^9
0 <= requests.length <= 1000
Each request has the form [partner_id, timestamp]
partner_id is a non-empty string
Timestamps for each partner are nondecreasing
Timestamps are nonnegative integers

Function Signature

def rate_limit_requests(requests, capacity, window_seconds):

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