express-sharp
express-sharp adds real-time image processing routes to your express application. Images are processed with sharp, a fast Node.js module for resizing images.
Installation
$ npm install express-sharp --save
See sharp installation for additional installation instructions.
Usage
Example app.js:
'use strict';
var express = require('express');
var app = express();
var scale = require('express-sharp');
var options = {baseHost: 'mybasehost.com'};
app.use('/my-scale', scale(options));
app.listen(3000));
Render http://mybasehost.com/image.jpg
with 400x400 pixels:
GET /my-scale/resize/400?url=%2Fimage.jpg HTTP/1.1
Host: localhost:3000
--> invokes in background:
GET image.jpg HTTP/1.1
Host: mybasehost.com
Same as above, but with 80% quality, webp
image type and with progressive enabled:
GET /my-scale/resize/400?format=webp&quality=80&progressive=true&url=%2Fimage.jpg HTTP/1.1
Host: localhost:3000
Options
var scale = require('express-sharp');
app.use('/some-path', scale(options));
Supported options:
baseHost
Specify the HTTP base host from which images will be requested.
cropMaxSize
The maximum length in pixels (width or height) a cropped Image is allowed to have.
Note: if this value is too high an attacker could use this to slow down your server.
Default is 2000
cors
Specify CORS options as described in cors docs. Example:
app.use('/some-path', scale({
cors: {
origin: 'http://example.com'
}
}));
If not specified, a Access-Control-Allow-Origin: *
header is being sent.
Path and query params
format
Output image format.
Default: webp
if supported else the output format of the requested image.
Valid values: every valid sharp output format string, i.e. jpeg
, gif
, webp
or raw
.
progressive
only available for jpeg and png formats:
See sharp docs for jpeg.
See sharp docs for png.
Use &progressive=true
to enable progressive scan.
quality
See sharp docs.
quality is a Number between 1 and 100.
crop
See sharp docs.
Use &crop=true
to enable the sharp cropping feature.
Default is `false.
Note: Both width
and height
params are neccessary for crop to work.
gravity
See sharp docs.
When the crop option is activated you can specify the gravity of the cropping.
Possible attributes of the optional gravity
are
north
, northeast
, east
, southeast
, south
, southwest
, west
, northwest
, center
and centre
.
Default is center
;
url
URL/path to original image.