RateLimiter

Token bucket rate limiter for controlling request throughput.

The Rate Limiter pattern controls the rate of operations to prevent overwhelming a system or service. It uses a token bucket algorithm where tokens are added at a fixed rate, and operations consume tokens.

Use Cases:

• API rate limiting

• Prevent service overload

• Comply with third-party API rate limits

• Control resource consumption

Token Bucket Algorithm:

• Tokens are added to a bucket at a fixed rate

• Each operation consumes one or more tokens

• If no tokens are available, the operation is throttled

• Allows bursts up to bucket capacity

Basic usage:

val limiter = RateLimiter.create(config = RateLimiterConfig(
    permitsPerSecond = 10.0,
    burstCapacity = 20
))

val result = limiter.tryExecute {
    callApi()
} // returns null if rate exceeded

Blocking execution:

val result = limiter.execute {
    callApi()
} // waits for available token

Sliding window variant:

val limiter = SlidingWindowRateLimiter.create(config = SlidingWindowConfig(
    maxRequests = 100,
    windowDuration = 1.minutes
))

Parameters