Struct DistributedSlidingWindowSpec 

pub struct DistributedSlidingWindowSpec { /* private fields */ }

Distributed sliding window implementation

Uses sorted sets in a distributed backend (e.g., Redis ZSET) to implement sliding window algorithm across multiple workers.

Redis Implementation

The sliding window is implemented using Redis sorted set:

• {key}:window - Sorted set of timestamps (score = timestamp, member = UUID)

Operations:

1. Acquire: Add current timestamp to sorted set if count < limit
2. Cleanup: Remove timestamps outside the window using ZREMRANGEBYSCORE
3. Count: Count timestamps within window using ZCOUNT

Example Lua Script

local window_key = KEYS[1]
local now = tonumber(ARGV[1])
local window_size = tonumber(ARGV[2])
local max_count = tonumber(ARGV[3])
local uuid = ARGV[4]

local cutoff = now - window_size * 1000
redis.call('ZREMRANGEBYSCORE', window_key, '-inf', cutoff)

local count = redis.call('ZCARD', window_key)
if count < max_count then
    redis.call('ZADD', window_key, now, uuid)
    redis.call('EXPIRE', window_key, window_size * 2)
    return 1
else
    return 0
end

Implementations

impl DistributedSlidingWindowSpec

pub fn new(key: String, config: RateLimitConfig) -> Self

Create a new distributed sliding window specification

pub fn lua_acquire_script() -> &'static str

Get the Lua script for atomic window acquisition

pub fn lua_available_script() -> &'static str

Get the Lua script for querying available permits

pub fn lua_time_until_script() -> &'static str

Get the Lua script for querying time until available

pub fn max_executions(&self) -> usize

Get the maximum number of executions allowed in the window

pub fn state(&self) -> &DistributedRateLimiterState

Get the state for implementing the distributed backend

pub fn try_acquire_fallback(&self) -> bool

Try to acquire using local fallback

Trait Implementations

impl Clone for DistributedSlidingWindowSpec

fn clone(&self) -> DistributedSlidingWindowSpec

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DistributedSlidingWindowSpec

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.