This project uses the Universal Base Docker images built by Red Hat and provides guidance on how to add best-practise Dockerfiles into your project.
This project contains three template Dockerfiles:
Dockerfile | Description |
---|---|
Dockerfile | A default Dockerfile for building and running your Node.js application |
Dockerfile-tools | A Dockerfile for developing or debugging your Node.js application |
Dockerfile-run | A multi-stage Dockerfile for building a "run" image for your application, based on the UBI 8 Node.js Minimal image |
In order to use these template files, copy the files from this project into your application directory.
The templates can most easily be installed into your project using either of the following mechanisms:
- All Files:
Use the "Clone or download" button and select "Download ZIP" to copy the entire set of templates, and copy those into your project. - Individual Files:
Use "wget" to download individual files using:wget https://raw.githubusercontent.com/NodeShift/docker/main/{file}
The Dockerfile template creates a Docker image for your application that:
- Uses the
registry.access.redhat.com/ubi8/nodejs-16:latest
image
The template also makes the following assumptions about your application:
- It listens on port 3000
- It can be started using
npm start
You can change these settings by updating the EXPOSE
and CMD
entries of the Dockerfile.
After any required changes have been made to the Dockerfile, you can build a Docker image for your application using the following command:
docker build -t my-nodejs-application -f Dockerfile .
where my-nodejs-application
is the name you want to give your created Docker image.
After the Docker image has been created for your application, you can run it using either of the following commands:
-
Run as an interactive application on your command line:
docker run -i -p 3000:3000 -t my-nodejs-application
This maps port 3000 in the Docker image to port 3000 on your machine. If you are using a different port, you will need to change the mapping.
-
Run as a daemon process:
docker run -d -p 3000:3000 -t my-nodejs-application
This uses the
-d
flag rather than the-i
flag to run the Docker image as a background task.
The Dockerfile-tools template creates a Docker image for your application that:
- Uses the
registry.access.redhat.com/ubi8/nodejs-16:latest
image - Provides a script for running in
dev
mode usingnodemon
- Provides a script for running in
debug
mode usingnode --inspect
The template also makes the following assumptions about your application:
- It listens on port 3000
- It can be started using
node server/server.js
You can change the port by editing the EXPOSE
entry in the Dockerfile-tools file, and the start command by editing the run-dev
and run-debug
scripts.
After any required changes have been made to the Dockerfile-tools, you can build a Docker image for your application using the following command:
docker build -t my-nodejs-application-tools -f Dockerfile-tools .
where my-nodejs-application-tools
is the name you want to give your created tools Docker image.
Running the image in Development Mode uses nodemon
to watch for changes in your application and automatically restart it as those changes are made.
To enable your local changes to be updated in the Docker image, you must map your local file system into the running Docker container, as follows:
- Generate a Linux version of your
node_modules
dependencies locally, by generating them inside the node:16 docker image:
docker run -i -v "$PWD"/package.json:/tmp/package.json -v "$PWD"/node_modules_linux:/tmp/node_modules -w /tmp -t node:16 npm install
This step only needs to be repeated if you modify your package.json file.
- Run the Docker tools image as an interactive application on your command line in dev mode:
docker run -i -p 3000:3000 -v "$PWD"/:/app -v "$PWD"/node_modules_linux:/app/node_modules -t my-nodejs-application-tools /bin/run-dev
This maps port 3000 in the Docker image to port 3000 on your machine. If you are using a different port, you will need to change the mapping. This command also maps your local directory into the Docker container, allowing you to modify your Node.js application code and see the changes running immediately in the container.
In order to run your application in debug mode:
- Run as an interactive applications on your command line in debug mode:
This maps port 3000 in the Docker image to port 3000 on your machine. If you are using a different port, you will need to change the mapping. This command also maps port 9229 in the image to the same port on your machine so that you can connect the debugger.
docker run -i -p 3000:3000 -p 9229:9229 -t my-nodejs-application-tools /bin/run-debug
If you wish to run your Docker tools image as a background task, switch the -i
flag to -d
on the command line.
The Dockerfile-run template creates a Docker image using a multi-stage build that:
- Retrieves your dependencies and compiles any native add-ons using the
registry.access.redhat.com/ubi8/nodejs-16:latest
image - Copies your dependencies into the
registry.access.redhat.com/ubi8/nodejs-16-minimal:latest
image for reduced size
The template also makes the following assumption about your application:
- It listens on port 3000
- It can be started using
npm start
You can change these settings by updating the EXPOSE
and CMD
entries of the Dockerfile-run template.
After any required changes have been made to the Dockerfile-run file, you can build a Docker image for your application using the following command:
docker build -t my-nodejs-application-run -f Dockerfile-run .
where my-nodejs-application-run
is the name you want to give your created Docker run image.
After the Docker run image has been created for your application, you can run it using either of the following commands:
-
Run as an interactive application on your command line:
docker run -i -p 3000:3000 -t my-nodejs-application-run
This maps port 3000 in the Docker image to port 3000 on your machine. If you are using a different port, you will need to change the mapping.
-
Run as a daemon process:
docker run -d -p 3000:3000 -t my-nodejs-application-run
This additionally uses the
-d
flag to run the Docker image as a background task.
In order to use your application's Docker image in a cloud it needs to be published. You can deploy to the image to the DockerHub registry using the following commands:
-
Log in to DockerHub:
docker login
This logs you into DockerHub using your Docker ID, where you have a namespace that matches your DockerHub ID.
-
Tag your application's Docker image with the name you want to use in DockerHub:
docker tag my-nodejs-application-run <namespace>/nodeserver:1.0.0
where
<namespace>
is your namespace in DockerHub. -
Publish your application's Docker image to DockerHub:
docker push <namespace>/nodeserver:1.0.0
where
<namespace>
is your namespace in DockerHub.