NestJS Fastify Media Service

A high-performance image processing library for NestJS applications using Fastify. Provides image conversion, resizing, and caching capabilities.

Features

• 🖼️ Multi-format Conversion - Convert between JPEG, PNG, WebP, and more
• 📏 Smart Resizing - Maintain aspect ratio while resizing
• ⚡ In-Memory Caching - Avoid repeated processing of same images
• 🔗 Base64 Output - Get ready-to-use Data URLs
• 🚀 Fastify Optimized - Built for NestJS Fastify adapter

Installation

npm install sharp @nestjs/platform-fastify

Quick Start

1. Import Module

import { Module } from '@nestjs/common';
import { NestFastifyMediaService } from 'nest-fastify-media';

@Module({
  providers: [NestFastifyMediaService],
  exports: [NestFastifyMediaService],
})
export class MediaModule {}

2. Use in Controller

import { Controller, Get } from '@nestjs/common';
import { NestFastifyMediaService } from 'nest-fastify-media';

@Controller('images')
export class ImageController {
  constructor(private readonly mediaService: NestFastifyMediaService) {}

  @Get('convert')
  async convertImage() {
    return {
      buffer: await this.mediaService.convertImage({
        imageUrl: 'https://example.com/image.jpg',
        outputFormat: 'webp',
        width: 800,
      }),
      base64: await this.mediaService.convertImageToBase64({
        imageUrl: 'https://example.com/image.jpg',
        outputFormat: 'png',
      }),
    };
  }
}

API Reference

convertImage(dto: ConvertImageDto): Promise<Buffer>

Converts and resizes an image, returning a Buffer.

convertImageToBase64(dto: ConvertImageDto): Promise<string>

Converts an image and returns as Base64 Data URL.

ConvertImageDto

| Parameter | Type | Default | Description | | -------------- | -------- | ------- | ----------------------------------- | | imageUrl | string | - | Source image URL (required) | | outputFormat | string | png | Output format (jpeg/png/webp) | | width | number | - | Target width in pixels | | height | number | - | Target height in pixels |

Examples

Basic Conversion

const buffer = await mediaService.convertImage({
  imageUrl: 'https://example.com/photo.jpg',
  outputFormat: 'webp',
});

Resizing with Base64 Output

const base64 = await mediaService.convertImageToBase64({
  imageUrl: 'https://example.com/photo.jpg',
  outputFormat: 'png',
  width: 300,
  height: 200,
});

HTML Usage

<img src="data:image/png;base64,..." alt="Converted Image" />

Caching

• Automatic in-memory caching
• Cache key format: [url]-[format]-[width]x[height]
• Subsequent identical requests return cached version