Real-time image processing for your express application.

Description

                      express-sharp    Express app         endpoint          image path    transformation                ┌─────────────────┐┌────────────────┐┌──────────────────┐ ┌────────┐https://example.com/path/to/my-scaler/images/my-image.jpg?w=100&h=50

Highlights

Table of contents

Install

$ yarn add express-sharp

Express server integration

importexpressfrom'express'import{expressSharp,FsAdapter,HttpAdapter}from'express-sharp'constapp=express()// Fetch original images via HTTPapp.use('/some-http-endpoint',expressSharp({imageAdapter:newHttpAdapter({prefixUrl:'http://example.com/images',}),}))// Alternative: Load original images from diskapp.use('/fs-endpoint',expressSharp({imageAdapter:newFsAdapter(path.join(__dirname,'images')),}))app.listen(3000)

curl http://my-server/express-sharp-endpoint/images/image.jpg?w=400&h=400

curl http://my-server/express-sharp-endpoint/images/image.jpg?w=400&h=400&f=webp&q=80&p

Server configuration

import{expressSharp}from'express-sharp'app.use('/some-http-endpoint',expressSharp(options))

Image Adapters

File System

import{FsAdapter}from'express-sharp'constadapter=newFsAdapter('/path/to/images')

HTTP

$ yarn add got

import{HttpAdapter}from'express-sharp'constadapter=newHttpAdapter({prefixUrl:'http://localhost:3000/images',})

Amazon S3

$ yarn add aws-sdk

import{S3Adapter}from'express-sharp'constbucketName='my-bucketname'constadapter=newS3Adapter(bucketname)

Custom

import{ImageAdapter}from'express-sharp'classMyAdapterimplementsImageAdapter{asyncfetch(id:string):Promise<Buffer|undefined>{if(imageDoesNotExist(id)){returnundefined}returnBuffer.from('my image blob')}}

Caching

constcache=newKeyv({namespace:'express-sharp'})app.use('/my-endpoint',expressSharp({    cache,imageAdapter: ...}))

constcache=newKeyv('redis://',{namespace:'express-sharp'}app.use('/my-endpoint',expressSharp({    cache,imageAdapter: ...}))

URL signing

import{createClient}from'express-sharp'constendpoint='https://example.com/my-express-sharp-endpoint'constsecret='test'constclient=createClient(endpoint,secret)constimageUrl=client.url('/foo.png',{width:500})// https://example.com/my-express-sharp-endpoint/foo.png?w=500&s=Of3ty8QY-NDhCsIrgIHvPvbokkDcxV8KtaYUB4NFRd8

Debug logging

$export DEBUG='my-app:*,express-sharp*'

Client integration

import{createClient}from'express-sharp'constclient=createClient('http://my-base-host','optional secret')constoriginalImageUrl='/foo.png'constoptions={width:500}constfooUrl=client.url(originalImageUrl,options)

License