Module ratelimit 

Per-host rate limiting and concurrency control Per-host rate limiting and concurrency control.

This module provides adaptive rate limiting for HTTP requests on a per-host basis. It prevents overwhelming servers with too many concurrent requests and respects server-provided rate limit headers.

Architecture

• [HostKey]: Represents a hostname/domain for rate limiting
• [Host]: Manages rate limiting, concurrency, and caching for a specific host
• [HostPool]: Coordinates multiple hosts and routes requests appropriately
• [HostConfig]: Configuration for per-host behavior
• [HostStats]: Statistics tracking for each host

Modules

config 🔒

headers 🔒

Handle rate limiting headers. Note that we might want to replace this module with https://github.com/mre/rate-limits at some point in the future.

host 🔒

pool 🔒

Structs

CacheableResponse 🔒

The result of a HTTP request, used for internal per-host caching. This abstraction exists, because Response cannot easily be cached since it does not implement Clone.

Host

Represents a single host with its own rate limiting, concurrency control, HTTP client configuration, and request cache.

HostConfig

Configuration for a specific host’s rate limiting behavior

HostConfigs

Per-host configuration overrides

HostKey

A type-safe representation of a hostname for rate limiting purposes.

HostPool

Manages a pool of Host instances and routes requests to appropriate hosts.

HostStats

Record and report statistics for a crate::ratelimit::Host

HostStatsMap

A HashMap mapping hosts to their HostStats

RateLimitConfig

Global rate limiting configuration that applies as defaults to all hosts

Type Aliases

ClientMap

Keep track of host-specific reqwest::Clients