Spring Boot: Basic Rate Limiting using Bucket4j

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Rate Limiting and Uses

Rate limiting is a strategy for restricting access to an API. It limits the number of calls that can be made to an endpoint within a certain time thus defending the API against overuse, malicious use, etc.

Bucket4j

It is a library based on the Token-bucket algorithm. As per the Token-bucket algorithm, there is a bucket with limited tokens as its capacity. The user needs to get a token to access an endpoint. If the bucket has no token, then reject the user request. We will also replenish the token at a fixed rate after the consumption.

Spring Boot Application

Create the Spring Boot starter project.

Spring Web and Lombok Selection.

Add the Maven Dependency.

<dependency>
   <groupId>com.bucket4j</groupId>
   <artifactId>bucket4j-core</artifactId>
   <version>8.1.0</version>
  </dependency>

A sample pom.xml of the application.

<?xml version="1.0" encoding="UTF-8"?>
<project…