Publishing a Docker container to the GitHub Container Registry

If you have ever developed a cool application and wanted to share it and make sure it runs on every platform, the easiest solution is to containerise and publish it.

Recently, I created a small Notes CLI app, and I decided to package it into a Docker image so anyone can run it with a single command. In this post, I’ll show you how you can do the same for your own project.

Click Here to see Demo of notes app

Create a Dockerfile §

#I have used alpine here instead of ubuntu b/c it's very lightweight and fast
FROM node:20-alpine
# create app folder
WORKDIR /app
# Copy package.json and package-lock.json into app folder
COPY package*.json ./
# we use --production flag b/c we dont want dev dependencies like nodemon
RUN npm install --production
# copy our application code into app folder
COPY app.js notes.js ./
# we create a data directory for persistent storage in container. -p makes sure no error is thrown if folder already present
RUN mkdir -p /data
# finally we change work directory to data
WORKDIR /data
# run our main file i.e app.js
ENTRYPOINT ["node", "/app/app.js"]

#I have used alpine here instead of ubuntu b/c it's very lightweight and fast
FROM node:20-alpine
# create app folder
WORKDIR /app
# Copy package.json and package-lock.json into app folder
COPY package*.json ./
# we use --production flag b/c we dont want dev dependencies like nodemon
RUN npm install --production
# copy our application code into app folder
COPY app.js notes.js ./
# we create a data directory for persistent storage in container. -p makes sure no error is thrown if folder already present
RUN mkdir -p /data
# finally we change work directory to data
WORKDIR /data
# run our main file i.e app.js
ENTRYPOINT ["node", "/app/app.js"]

create a .dockerignore file to exclude unnecessary files like node_modules

Create a GitHub Personal Access Token §

We will use this generated token to get logged in to the GitHub Container Registry.

Create it with following scopes by going to GitHub → Settings → Developer settings → Personal access tokens → Tokens (classic) - this page here

• write:packages
• read:packages

export CR_PAT=your_token_here
echo $CR_PAT | docker login ghcr.io -u taimourz --password-stdin
docker build -t ghcr.io/taimourz/notes-cli:latest .

export CR_PAT=your_token_here
echo $CR_PAT | docker login ghcr.io -u taimourz --password-stdin
docker build -t ghcr.io/taimourz/notes-cli:latest .

Finally test Your Image Locally and Push to GitHub Container Registry §

docker run --rm ghcr.io/taimourz/notes-cli:latest --help
# Create a test directory for data
mkdir -p ~/test-notes
# adding notes
docker run --rm -v ~/test-notes:/data ghcr.io/taimourz/notes-cli:latest add --title="Test" --body="My first containerized note"
# listing notes
docker run --rm -v ~/test-notes:/data ghcr.io/taimourz/notes-cli:latest list
# push into github registry
docker push ghcr.io/taimourz/notes-cli:latest
# pull to see if it works
docker pull ghcr.io/taimourz/notes-cli:latest

docker run --rm ghcr.io/taimourz/notes-cli:latest --help
# Create a test directory for data
mkdir -p ~/test-notes
# adding notes
docker run --rm -v ~/test-notes:/data ghcr.io/taimourz/notes-cli:latest add --title="Test" --body="My first containerized note"
# listing notes
docker run --rm -v ~/test-notes:/data ghcr.io/taimourz/notes-cli:latest list
# push into github registry
docker push ghcr.io/taimourz/notes-cli:latest
# pull to see if it works
docker pull ghcr.io/taimourz/notes-cli:latest

• --rm: Automatically remove the container after it exits
• -v ~/test-notes:/data: Mount a local directory for persistent data storage

Here is how I did it.

How to unpublish/delete, change visibility §

By default the packages are private. If you want to share it with everyone, make them public by going to https://github.com/taimourz?tab=packages You can also delete the package here.

There is also an option to delete it using terminal like this

#login into GitHub Container Registry
echo $CR_PAT | gh auth login --with-token          # if token
docker login ghcr.io -u taimourz --password-stdin  # if password
# verify package exists
gh api /user/packages/container/notes-cli
# delete the package
gh api -X DELETE /user/packages/container/notes-cli

#login into GitHub Container Registry
echo $CR_PAT | gh auth login --with-token          # if token
docker login ghcr.io -u taimourz --password-stdin  # if password
# verify package exists
gh api /user/packages/container/notes-cli
# delete the package
gh api -X DELETE /user/packages/container/notes-cli