[SOLVED] Hosting ASP.NET on Raspberry Pi 3B+ for local network

Issue

I am trying to host an API (ASP.NET) on my Raspberri Pi 3B +. I would like to access this API swagger page from my laptop/phone/pc etc.

What I’ve tried until now:
Installed, compiled, built and ran the web application with dotnet on my RPi.

running dotnet --info on the RPi provides us the following information:

.NET SDK (reflecting any global.json):
 Version:   5.0.405
 Commit:    63325e1c7d

Runtime Environment:
 OS Name:     raspbian
 OS Version:  11
 OS Platform: Linux
 RID:         linux-arm
 Base Path:   /usr/share/dotnet/sdk/5.0.405/

Host (useful for support):
  Version: 5.0.14
  Commit:  d5b56c6327

.NET SDKs installed:
  5.0.405 [/usr/share/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 5.0.14 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 5.0.14 [/usr/share/dotnet/shared/Microsoft.NETCore.App]

When I run the program (filepath ~/first-rpi-api/bin/Release/net5.0/publish/first-rpi-api)

I get the following:

info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://localhost:5000
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: https://localhost:5001
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: /home/pi/first-rpi-api/bin/Release/net5.0/publish

The default URL for the swagger UI would be : https://localhost:44335/swagger/index.html
However when I try to access the API from my PC on URL : https://RPi_IP:5000/swagger/index.html

I get ERR_CONNECTION_REFUSED

How do I fix this ? Have I missed something and how would I approach this problem ?

Solution

Using the previous answer (refering to omajid’s answer) provides us only a temporary solution.

Whenever you reboot the Raspberry Pi you would need to execute the command

export ASPNETCORE_URLS="http://*:5000;https://*:5001"

again and again.

To prevent this, I suggest using the IHostBuilder.UseUrls("URLS") method.

In your case you would need to edit your Program.cs and add the following line in the CreateHostBuilder method.

public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();

                    //THIS LINE
                    webBuilder.UseUrls("http://*:5000;https://*:5001"); 
                });

This will automatically ensures that you can access the API from whichever device you’d like.

You can read more about this in this article :

Answered By – schweppes0x

Answer Checked By – Cary Denson (BugsFixing Admin)