Containerize ASP.NET Core web app

This tutorial will help you to containerize / dockerize ASP.NET Core web app.

• Source code can be found at: https://github.com/abhishek-pradhan/aspnetcore-docker

Docker image + container for ASP.NET Core web app

Shows 2 options on how to use Dockerfile in a sample ASP.NET Core 2.1 web app

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

• Docker Desktop CE (I used for Windows)
• Visual Studio Code (v1.41.1)
• Visual Studio CE (2017)

Note: Depending on the operating system of the host machines(s) that will build or run the containers, the image specified in the FROM statement may need to be changed.

Since I wanted to create Windows container, I switched Docker desktop to Windows container. However, if you want to use linux containers too, it works too. Only difference between Windows & Linux containers is change in Dockerfile. I have provided both Linux & Windows dockerfiles. For Linux, use Dockerfile with linux name in it (webapp-linux.Dockerfile or Dockerfile-linux)

Tip: No need to create Dockerfile on your own, you can create Dockerfile by navigating to WebApp folder / or folder where you have your .csproj file & then opening it in VS Code:

VS Code -> F1 -> Docker: Add Docker Files to Workspace... 

(you will get couple of options like Windows or Linux env, at the end it creates ‘Dockerfile’ for you!)

Option 1

Docker file for WebApp with references to Class Libraries: Use Dockerfile (webapp.Dockerfile) from aspnetcore-docker\src folder & run below below Docker commands

Option 2

Docker file for WebApp with NO references to Class Libraries: Comment out ClassLibrary1.csproj reference from src/WebApp/WebApp.csproj file & also comment out 2 lines having reference to ClassLibrary src/WebApp/Controllers/HomeController.cs. Use Dockerfile from aspnetcore-docker\src\WebApp\ folder & run below below Docker commands:

Docker commands (used for above 2 options)

1. Now create Docker image from Dockerfile:

   (applicable for Option 1: run below command from folder: aspnetcore-docker\src) Windows container image:

    docker build -t webapp:latest -f WebApp.dockerfile .
   

   OR Linux container image:

      docker build -t webapp:latest -f WebApp-linux.dockerfile .
   

   OR (applicable for Option 2: run below command from folder: aspnetcore-docker\src\WebApp) Windows container image:

      docker build -t webapp:latest .
   

   OR Linux container image:

      docker build -t webapp:latest -f Dockerfile-linux .
   

   (1.1) If docker build is successfull, you should see docker image webapp:latest by running

    docker images
   

2. Create docker container from image:

    docker run --name=webapp -d -p 8080:80 webapp
   

   (2.1) If docker run is successfull, you should see docker container webapp by running:

    docker ps
   

3. Now you can get ip address of docker container, at the end, check IPAddress field:

    docker inspect webapp
   

4. Access webapp via (took couple of seconds for me, before you can access site):

    http://127.0.0.1:8080
   

   OR

    http://containerIPAddress
   

Tip: Debug

If you face any issue while creating / building images, use logs or inspect command:

  docker logs <containerID>

  docker inspect <containerID>

Docker commands to cleanup

1. Stop running docker container:

    docker stop webapp
   

2. Remove docker container:

    docker rm webapp
   

3. Remove docker image:

    docker rmi webapp
   

Result / Output