Created
August 15, 2016 11:03
-
-
Save btd/64d39357e8a74a6b6a1479f4d94c2d34 to your computer and use it in GitHub Desktop.
Very basic image proxy
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
'use strict'; | |
const express = require('express'); | |
const crypto = require('crypto'); | |
const got = require('got'); | |
const signingKey = 'some sort of key here'; | |
const proxyHeaders = [ | |
'content-length', | |
'content-type', | |
'etag', | |
'expires', | |
'last-modified', | |
'vary' | |
]; | |
var app = express() | |
app.disable('x-powered-by'); | |
app.get('/:imageSignature/:imageUrl', function (req, res, next) { | |
const imageSignature = req.params.imageSignature; | |
const imageUrl = req.params.imageUrl; | |
// compare signature | |
const hmac = crypto.createHmac('sha256', signingKey); | |
hmac.update(imageUrl, 'utf8'); | |
var expectedSignature = hmac.digest('hex'); | |
console.log(req.params) | |
console.log('expectedSignature', expectedSignature); | |
if(expectedSignature !== imageSignature) { | |
var err = new Error('Requested signature does not match'); | |
err.status = 400; | |
return next(err); | |
} | |
console.log('Request headers', req.headers); | |
var headers = { | |
'Accept': req.headers.accept || 'image/*', | |
'User-Agent': req.headers['user-agent'], | |
}; | |
return got.get(imageUrl, { headers: headers }) | |
.then(function(imageResponse) { | |
console.log('response headers', imageResponse.headers) | |
proxyHeaders.forEach(function(header) { | |
var headerValue = imageResponse.headers[header]; | |
if(headerValue) { | |
res.setHeader(header, headerValue); | |
console.log('set header', header, headerValue) | |
} | |
}) | |
res.status(imageResponse.statusCode) | |
.send(imageResponse.body) | |
}) | |
.catch(function(err) { | |
err.status = 400; | |
return next(err); | |
}) | |
}) | |
app.listen(3000) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment