Node.js is a software platform for scalable server-side and networking applications. Node.js applications are written in JavaScript and can be run within the Node.js runtime on Mac OS X, Windows, and Linux without changes.
Node.js applications are designed to maximize throughput and efficiency, using non-blocking I/O and asynchronous events. Node.js applications run single-threaded, although Node.js uses multiple threads for file and network events. Node.js is commonly used for real-time applications due to its asynchronous nature.
Node.js internally uses the Google V8 JavaScript engine to execute code; a large percentage of the basic modules are written in JavaScript. Node.js contains a built-in, asynchronous I/O library for file, socket, and HTTP communication. The HTTP and socket support allows Node.js to act as a web server without additional software such as Apache.
Create a Dockerfile in your Node.js app project:
FROM platten/alpine-node.js
# replace this with your application's default port
EXPOSE 8888
You can then build and run the Docker image:
$ docker build -t my-nodejs-app .
$ docker run -it --rm --name my-running-app my-nodejs-app
Note: The image assumes that your application has a file named package.json listing its dependencies and defining its start script.
For many simple, single file projects, you may find it inconvenient to write a complete Dockerfile. In such cases, you can run a Node.js script by using the Node.js Docker image directly:
$ docker run -it --rm --name my-running-script -v "$PWD":/usr/src/app -w /usr/src/app node:4 node your-daemon-or-script.js
This image is based on the popular Alpine Linux project, available in the alpine official image. Alpine Linux is much smaller than most distribution base images (~5MB), and thus leads to much slimmer images in general.
This variant is highly recommended when final image size being as small as possible is desired. The main caveat to note is that it does use musl libc instead of glibc and friends, so certain software might run into issues depending on the depth of their libc requirements. However, most software doesn't have an issue with this, so this variant is usually a very safe choice. See this Hacker News comment thread for more discussion of the issues that might arise and some pro/con comparisons of using Alpine-based images.
To minimize image size, it's uncommon for additional related tools (such as git or bash) to be included in Alpine-based images. Using this image as a base, add the things you need in your own Dockerfile (see the alpine image description for examples of how to install packages if you are unfamiliar). To further decrease size this image has been compiled without NPM. Security for node is handled by grsecurity/PaX.