A simple, yet practical command-line utility enabling .NET developers to test web applications served by IIS Express on remote devices.
Are you a .NET developer building mobile web applications? Have you ever been frustrated by the fact that there's no easy way to enable IIS Express to accept connections from remote devices?...
There's no need to install
iisexpress-proxy if you're using
npm@^5.2.0; you can simply run it with
npx. If you're using an older version of
npm, you'll most likely want
iisexpress-proxy installed as a global module:
npm install -g iisexpress-proxy
Note: You need to have Node.js installed.
If you're using
npx iisexpress-proxy localPort to proxyPort
Alternatively, if you installed iisexpress-proxy as a global
iisexpress-proxy localPort to proxyPort
For instance, if your application's IIS Express port is 51123, run this in the Command Prompt:
iisexpress-proxy 51123 to 3000
The program will list the external addresses you can use for testing your application on remote devices.
iisexpress-proxy defaults to http, so if your application is running https, then include the full URL.
iisexpress-proxy https://localhost:51123 to 3000
Note that this will terminate HTTPS. On your destination machine, connect to port
3000 using HTTP, not HTTPS.
If you want the proxy itself to serve HTTPS, you can specify the target with the full URL as well.
iisexpress-proxy https://localhost:51123 to https://*:3000
This will generate a self-signed certificate and use it, openssl must be in
PATH for this to work.
If you're on Windows, the easiest way to get openssl is to use Git Bash that comes with it pre-installed.
If you want to bind to a specific interface instead of all of them, use its IP in the target URL, e.g.
https://10.0.0.1:3000. Note that the right-hand part cannot be a domain name.
Advanced usage (VPN, virtual hosts, etc.)
You can also use iisexpress-proxy to expose an IIS server instance running on a different host accessible through VPN, like this:
iisexpress-proxy host:port to proxyHost:proxyPort
For instance, let's conside this scenario:
- the application is running on 192.168.96.3:5000 and it only accepts connections from clients within a VPN;
- your development machine has a network interface within the same VPN and another publicly accessible one (192.168.0.102);
- you need to test the application from mobile devices without having to add those devices to the VPN.
By running this in the Command Prompt:
iisexpress-proxy 192.168.96.3:5000 to 192.168.0.102:3000
...you'll be able to access the application by pointing the mobile devices to 192.168.0.102:3000.
For another advanced example, consider that you're on public Wifi and don't want to publicly expose your dev server. You could set up a VPN between your laptop and your phone and only expose the server on the VPN interface (10.0.0.1). Then you can run
iisexpress-proxy 5000 to 10.0.0.1:8080
...and open http://10.0.0.1:8080 on your phone with VPN enabled, while other wifi users won't be able to connect.
Note: This functionality was added at v1.1.0 (released 10/21/2015).
If you don't want using generated certificates you could provide your own certificate and key using
iisexpress-proxy https://localhost:51123 to https://*:3000 --key=./your-key.pem --cert=./your-cert.pem
Note: This functionality was added at v1.7.0 (released 02/14/2022).
iisexpress-proxy doesn't work in scenarios involving integrated Windows authentication (see issue #here).
How does it work
It's proxying the HTTP traffic on
proxyPort on all the available network interfaces and it's also changing the origin of the host header, allowing you to test web applications hosted by IIS Express on various remote devices (mobile devices, other desktops, etc.).
If you need to access the original host requested by the browser, the request headers will include X-Forward headers. In ASP.NET,
Request.Headers["x-forwarded-host"] will contain the requested host.
Credits and attributions
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