Module sliding_window 

Sliding Window Operators

Implementation of sliding (hopping) windows for stream processing.

Sliding windows are fixed-size windows that overlap. Each event can belong to multiple windows. The window size defines the duration, and the slide defines how much each window advances.

Example

Window size: 1 hour, Slide: 15 minutes

Window 1: [00:00, 01:00)
Window 2: [00:15, 01:15)
Window 3: [00:30, 01:30)
Window 4: [00:45, 01:45)

An event at 00:40 belongs to windows 1, 2, 3

Performance

• Each event is assigned to ceil(size / slide) windows
• Uses SmallVec<[WindowId; 4]> to avoid heap allocation for common cases
• State is stored per-window, so memory usage scales with active windows

Usage

use laminar_core::operator::sliding_window::{
    SlidingWindowAssigner, SlidingWindowOperator,
};
use laminar_core::operator::window::CountAggregator;
use std::time::Duration;

// Create a 1-hour sliding window with 15-minute slide
let assigner = SlidingWindowAssigner::new(
    Duration::from_secs(3600),  // 1 hour window
    Duration::from_secs(900),   // 15 minute slide
);
let operator = SlidingWindowOperator::new(
    assigner,
    CountAggregator::new(),
    Duration::from_secs(60), // 1 minute grace period
);

Structs

SlidingWindowAssigner

Sliding window assigner.

SlidingWindowOperator

Sliding window operator.