Redis Rate Limiter is a module that allows you to rate limit requests to your NestJS application using Redis.

Custom package:

• @predator/common : to install common package in the workspace run pnpm add @predator/common or pnpm link @predator/common
  • It has the rate limiting logic and the config module
  • To use the rate limiting module, import RateLimitingModule from @predator/common and use the registerAsync method to register the module.
  • The registerAsync method takes two arguments:
    • The first argument is the storage configuration, which is the configuration for the Redis connection.
    • The second argument is the rate limit configuration, which is an array of objects that contain the name, window, and requests for each rate limit.
• In @predator/common, another module is created "config-module" which is used to load the configuration from the .env file.
  • To use the config module, import ConfigModule from @predator/common and use the register method to register the module.
  • The register method takes one argument:
    • The first argument is the configuration class, which is the class that contains the configuration for the Redis connection.

Package used:

• @nest-lab/throttler-storage-redis
• ioredis
• @nestjs/throttler
• pnpm

• The rate limiting logic is implemented in the @predator/common package.
• The @nestjs/throttler package is used to implement the rate limiting logic in the service-one and service-two applications.
• The @nest-lab/throttler-storage-redis package is used to implement the Redis storage for the rate limiting logic in the service-one and service-two applications.
• The ioredis package is used to implement the Redis client in the service-one and service-two applications.
• The RequestRateTracker class is used to generate the rate limit key. It uses the request URL and the IP address to generate the key.
• The RequestRateLimiter class is used to implement the rate limiting logic. It uses the RequestRateTracker class to generate the rate limit key and the BaseLimiter class to implement the rate limiting logic.
• The BaseLimiter class is a base class for the rate limiters. It contains the common logic for the rate limiters.
• The RequestTracker interface is used to generate the rate limit key. It contains the getRequestIp method to get the IP address from the request and the generateKey method to generate the rate limit key.

• Install the common package in the workspace: pnpm add @predator/common or pnpm link @predator/common
• Import RateLimitingModule from @predator/common and use the registerAsync method to register the module.
• The registerAsync method takes two arguments:
  • The first argument is the storage configuration, which is the configuration for the Redis connection.
  • The second argument is the rate limit configuration, which is an array of objects that contain the name, window, and requests for each rate limit.
• The rate limit configuration is an array of objects that contain the name, window, and requests for each rate limit.
  • The name is the name of the rate limiter.
  • The window is the time window for the rate limiter in milliseconds.
  • The requests is the number of requests allowed in the time window.
• Decorate the controller with the @Throttle decorator.
  • The @Throttle decorator takes one argument:
    • The first argument is the rate limit configuration, which is the configuration for the rate limiter.
  • The rate limit configuration is an object that contains the name and the limit for the rate limiter.
    • The name is the name of the rate limiter.
    • The limit is the number of requests allowed in the time window.

• The service-one application is an example of how to use the rate limiting module.
• The service-two application is an example of how to use the rate limiting module.

Generated rate limit key: AppController-getHello:service-one:ip(::1) ThrottlerLimitDetail: Tracker is throttled for exceeding the rate limit of 1 in 10000ms | Api Endpoint - AppController | getHello | Total Hits - 2