simple HTTP proxy based on hyperquest
npm install hyperproxhyperprox
---------
simple HTTP proxy based on hyperquest
``
$ npm install hyperprox
`js
var http = require("http")
var hyperprox = require('hyperprox')
var backends = hyperprox(function(req){
// calculate the proxy destination
var port = req.url=='/a' ? 8081 : 8082
return 'http://127.0.0.1:' + port
})
// the front facing web server
var router = http.createServer(backends.handler())
backends.on('request', function(req, res){
})
backends.on('route', function(req, address){
})
var serverA = http.createServer(function(req, res){
res.end('serverA')
})
var serverB = http.createServer(function(req, res){
res.end('serverB')
})
router.listen(8080)
serverA.listen(8081)
serverB.listen(8082)
`
We can generate a duplex stream for a request that will auto-route - this lets us filter the input and output:
`js
var through = require('through2')
var backends = hyperprox(function(req){
var port = req.url=='/a' ? 8081 : 8082
return 'http://127.0.0.1:' + port
})
var router = http.createServer(function(req, res){
var proxy = backends.duplex(req, res)
// filter the request body
var inputFilter = through(function(chunk, enc, next){
this.push(chunk.toString() + 'a')
next()
})
// filter the response body
var outputFilter = through(function(chunk, enc, next){
this.push(chunk.toUpperCase())
next()
})
// REQUEST -> INPUT FILTER -> PROXY -> OUTPUT FILTER -> RESPONSE
req.pipe(inputFilter).pipe(proxy).pipe(outputFilter).pipe(res)
})
`
Your routing function can be asynchronous - this means you can ask an external service for routing data:
If you define next in the parameters then it will be treated as an async router.
`js
var proxy = hyperprox(function(req, next){
loadRoute(req.url, function(err, address){
next(err, address)
})
})
`
#### hyperprox.proxy(req, res, address, [input, output])
A direct proxy function that will send req via address to res
Input and output are optional override streams to replace req and res
#### var backends = hyperprox(function(req, next){})
Create a new proxy by passing a function that will resolve the backend address and pass it to the 'next' function
#### backends.handler()
Return a function(req,res){} that will proxy requests using the routing function
#### backends.proxy(req, res, address, [input, output])
A direct proxy that will pipe req via address and to res
If input and output are provided - they will be used as the streams rather than req and res
#### backends.resolve(req, done)
The resolving function that goes via the user supplied function
#### backends.duplex(req, res)
Return a duplex stream going through the backend - you can write it to the original request / response how you want:
`js`
var duplex = backends.duplex(req, res)
req.pipe(duplex).pipe(res)
If there is an error with routing the response will be set to 500 and the backend skipped
#### backends.on('request', function(req, res){})
when a request arrives at the proxy
#### backends.on('route', function(req, address){})`
Once a routing decision has been made
MIT