Nginx Reverse Proxy to ASP.NET Core – Separate Docker Containers

Kestrel is the web server that is included by default in ASP.NET Core new-project templates. If your application accepts requests only from an internal network, you can use Kestrel by itself.

But If you expose your application to the Internet, you must use IIS, Nginx, or Apache as a reverse proxy server. A reverse proxy server receives HTTP requests from the Internet and forwards them to Kestrel after some preliminary handling, as shown in the following diagram

This project is a sample how to setup a reverse proxy between Nginx and an ASP.NET Core application in the same box.

The sample creates two separate containers: one for the application and one for the reverse proxy. Then It uses Docker compose to bring them up together and handle the network bridge between them.

Docker configuration

That configuration defines two services: app and proxy.

Docker-Compose.yml:

version: '2'
 
services:
  app:
    build:
      context:  ./app
      dockerfile: Dockerfile
    expose:
      - "5000"
 
  proxy:
    build:
      context:  ./nginx
      dockerfile: Dockerfile
    ports:
      - "8084:80"
    links:
      - app

App Dockerfile:

FROM microsoft/aspnetcore:1.1
 
WORKDIR /app
COPY bin/Debug/netcoreapp1.1/publish .
 
ENV ASPNETCORE_URLS http://+:5000
EXPOSE 5000
 
ENTRYPOINT ["dotnet", "app.dll"]

Proxy Dockerfile:

FROM nginx
COPY nginx.conf /etc/nginx/nginx.conf