HTTP Utils TS

This is a simple library which provides a set of utilities to work with HTTP requests and responses in TypeScript. Especially, for caching and applying a rate limit to requests.

Run demo

Run the following command to install the dependencies

npm i

Run the demo

npm run demo

Installation

npm install @nathangasc/http-utils-ts

The following is an example to demonstrates how to use the library to fetch quotes from the Type Fit API and cache the responses in the ./cache directory. The rate limit is set to 10 requests per second.

import { HttpUtils } from '@nathangasc/http-utils-ts'

class ApiWrapper extends HttpUtils {
    constructor() {
        super(
            {
                cache: { path: './cache', durationMiliseconds: 3000, deleteOnExpire: true },
                rateLimit: { maxRequest: 10, perMiliseconds: 100, deleteOnExpire: true, waitTillLimitReset: true }
            }
        )
    }

    private domain = "https://type.fit/"

    async getQuotes() {
        let response = await this.fetch(this.domain+"api/quotes")
        return JSON.parse(response.body) as { text: string, author: string }[]
    }
}

let main = async () => {
    const api = new ApiWrapper()
    await api.getQuotes()
    setTimeout(async () => {
        await api.getQuotes()
    }, 2000)
}
main()

Usage

The library provides a class HttpUtils which can be extended to create a custom API wrapper.

Cache

Requests are cached by default. The cache is stored in the given directory by the HttpUtils constructor.

Disable cache

Sometimes, you may want to disable the cache for some requests. You can do this by setting the noCache option to false in the fetch method. The cache is created based on the request URL. So if you request multiple time the same URL, the response will be cached and returned from the cache.

let response = await this.fetch("https://type.fit/api/quotes", undefined, true)

Rate Limit

The rate limit define how many requests can be made in a given time frame. The rate limit is set by the rateLimit option in the HttpUtils constructor.

Catch rate limit error

When the rate limit is reached, the library will throw a RateLimitError error. You can catch this error and wait for the rate limit to reset.

let response = await this.fetch("https://type.fit/api/quotes").catch((error) => {
    if (error instanceof RateLimitError) {
        console.error("Rate limit reached!")
    }
})