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    Proxy your HTTP requests to another server, with hooks. This fastify plugin forwards all requests received with a given prefix (or none) to an upstream. All Fastify hooks are still applied.

    fastify-http-proxy is built on top of fastify-reply-from, which enables single route proxying.

    This plugin can be used in a variety of circumstances, for example if you have to proxy an internal domain to an external domain (useful to avoid CORS problems) or to implement your own API gateway for a microservices architecture.


    Fastify 3.x. See this branch and related versions for Fastify 1.x compatibility and this tag for Fastify 2.x.


    npm i fastify-http-proxy fastify


    const Fastify = require('fastify')
    const server = Fastify()
    server.register(require('fastify-http-proxy'), {
      upstream: '',
      prefix: '/api', // optional
      http2: false // optional

    This will proxy any request starting with /api to For instance http://localhost:3000/api/users will be proxied to

    If you want to have different proxies on different prefixes you can register multiple instances of the plugin as shown in the following snippet:

    const Fastify = require('fastify')
    const server = Fastify()
    const proxy = require('fastify-http-proxy')
    // /api/x will be proxied to
    server.register(proxy, {
      upstream: '',
      prefix: '/api', // optional
      http2: false // optional
    // /auth/user will be proxied to
    server.register(proxy, {
      upstream: '',
      prefix: '/auth', // optional
      rewritePrefix: '/signon', // optional
      http2: false // optional

    Notice that in this case it is important to use the prefix option to tell the proxy how to properly route the requests across different upstreams.

    Also notice paths in upstream are ignored, so you need to use rewritePrefix to specify the target base path.

    For other examples, see example.js.

    Request tracking

    fastify-http-proxy can track and pipe the request-id across the upstreams. Using the hyperid module and the fastify-reply-from built-in options a fairly simple example would look like this:

    const Fastify = require('fastify')
    const proxy = require('fastify-http-proxy')
    const hyperid = require('hyperid')
    const server = Fastify()
    const uuid = hyperid()
    server.register(proxy, {
      upstream: 'http://localhost:4001',
      replyOptions: {
        rewriteRequestHeaders: (originalReq, headers) => ({...headers, 'request-id': uuid()})


    This fastify plugin supports all the options of fastify-reply-from plus the following.

    Note that this plugin is fully encapsulated, and non-JSON payloads will be streamed directly to the destination.


    An URL (including protocol) that represents the target server to use for proxying.


    The prefix to mount this plugin on. All the requests to the current server starting with the given prefix will be proxied to the provided upstream.

    The prefix will be removed from the URL when forwarding the HTTP request.


    Rewrite the prefix to the specified string. Default: ''.


    A preHandler to be applied on all routes. Useful for performing actions before the proxy is executed (e.g. check for authentication).


    When this option is false, you will be able to access the body but it will also disable direct pass through of the payload. As a result, it is left up to the implementation to properly parse and proxy the payload correctly.

    For example, if you are expecting a payload of type application/xml, then you would have to add a parser for it like so:

    fastify.addContentTypeParser('application/xml', (req, done) => {
      const parsedBody = parsingCode(req)
      done(null, parsedBody)


    An object accessible within the preHandler via reply.context.config. See Config in the Fastify documentation for information on this option. Note: this is merged with other configuration passed to the route.


    Object with reply options for fastify-reply-from.


    An array that contains the types of the methods. Default: ['DELETE', 'GET', 'HEAD', 'PATCH', 'POST', 'PUT', 'OPTIONS'].


    This module has partial support for forwarding websockets by passing a websocket option. All those options are going to be forwarded to fastify-websocket. A few things are missing:

    1. forwarding headers as well as rewriteHeaders
    2. request id logging
    3. support ignoreTrailingSlash

    Pull requests are welcome to finish this feature.


    The following benchmarks where generated on a dedicated server with an Intel(R) Core(TM) i7-7700 CPU @ 3.60GHz and 64GB of RAM:

    Framework req/sec
    express-http-proxy 2557
    http-proxy 9519
    fastify-http-proxy 15919

    The results were gathered on the second run of autocannon -c 100 -d 5 URL.


    • [ ] Perform validations for incoming data
    • [ ] Finish implementing websocket (follow TODO)




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