Containerize

All the files needed to build the container and compose can be found in the DatingApp repository.

Install Docker CE

sudo apt update
sudo apt-get install \
     apt-transport-https \
     ca-certificates \
     curl \
     gnupg2 \
     software-properties-common
curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -
sudo add-apt-repository \
  "deb [arch=amd64] https://download.docker.com/linux/debian \
  $(lsb_release -cs) \
  stable"
sudo apt update
sudo apt install docker-ce

Verify the installation by running the hello-world container

sudo docker run hello-world

Configure Docker to be run by a non root user

sudo groupadd docker
sudo usermod -aG docker $USER

Log out and log back in, then test running hello-world without sudo (on my machine this step required a full restart)

docker run hello-world

Extension

There is a good extension for vscode named Docker from peterjausovec.vscode-docker

Publish the application

cd DatingApp.API
dotnet publish -c Release --output build

Dockerfile

The image microsoft/dotnet:runtime is for running an application in production. There is also an image for building and testing using Docker, but I will not use that here.

In the root folder of DatingApp.API create a new file Dockerfile

FROM microsoft/dotnet:2.1-aspnetcore-runtime
WORKDIR /app
COPY ./bin/Release/netcoreapp2.1/publish/. ./

ENTRYPOINT ["dotnet", "DatingApp.API.dll"]

Create the image (this will take a few minutes the first time it is run)

docker build -t teo/datingapp:runtime .

Run the image (this step will fail because there is no MySql)

docker run -it --rm -p 5001:80 --name datingapp_production teo/datingapp:runtime

Install Docker Compose

To run DatingApp we need a database.

To orchestrate two Docker containers, one for dotnet and one for MySql, we use Docker Compose.

On Windows and Osx Compose is already installed with Docker.

Official installation guide

Check the latest Compose version on the compose releases

# Download compose (use the latest version)
sudo curl -L https://github.com/docker/compose/releases/download/1.22.0/docker-compose-$(uname -s)-$(uname -m) -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose

Test the installation.

$ docker-compose --version

Prepare the database script

export ASPNETCORE_ENVIRONMENT=Production
dotnet ef migrations script --output "_MySql_Init_Script/generate_datingapp_db.sql"

Add Compose to DatingApp

Our compose will use a database container using MySql version 5.7 (I had some problems with version 8)

Then configure the environment of the dotnet container to use a connection string to the new db.

Create a file docker-compose.yml

version: '3.0'

services:
  datingdb:
    image: mysql:5.7
    environment:
      MYSQL_RANDOM_ROOT_PASSWORD: 1
      MYSQL_DATABASE: datingappschema
      MYSQL_USER: datingappuser
      MYSQL_PASSWORD: password
    volumes:
      - dbdata:/var/lib/mysql
      - ./_MySql_Init_Script:/docker-entrypoint-initdb.d

  datingapp:
    depends_on:
      - datingdb
    image: teo/datingapp:runtime
    environment:
      - ASPNETCORE_ENVIRONMENT=Production
      - ConnectionStrings__DatingDbConnection=Server=datingdb;Database=datingappschema;Uid=datingappuser;Pwd=password;
    env_file: ./datingapp.env
    build:
      context: .
    ports:
      - '8080:80'

volumes:
  dbdata:

Create an evironment file to store secrets parameters

cp datingapp_example.env datingapp.env

Open datingapp.env (it is in gitignore to avoid publishing) and insert the correct values

# JWT toke secret
AppSettings__TokenSecret="tokensecretforproduction"

# Cloudinary
CloudinarySettings__CloudName="name"
CloudinarySettings__ApiKey="key"
CloudinarySettings__ApiSecret="secret"

Run compose (the first run is a bit slow)

docker-compose up
# to force rebuild
docker-compose up --build

Test the application.

Stop compose

docker-compose down
# Stop and remove all volumes
docker-compose down -v