Stop Installing Node Modules on Your Docker Host - Install Them in the Container Instead

Are you tired of dealing with inconsistent Node.js environments across your development team? Local installation problems can waste valuable development time.

Docker containers provide the perfect solution by creating isolated, consistent environments. By installing all dependencies within the container itself, you ensure every developer works with identical setups.

In this guide, we'll show you exactly how to install node modules inside Docker containers instead of your host machine, giving you a reliable and portable development environment that works everywhere.

Why Install Node Modules Inside the Container?

When you install node modules inside a Docker container, you get three main benefits that make your life easier.

(1) First, your app will work the same way everywhere because all the needed software is packaged together. (2) Second, you can easily move your app between different computers since everything it requires is inside the container. (3) Third, your computer stays clean because all the extra software your app requires stays inside the container instead of being installed on your computer.

Step-by-step guide

Let's walk through setting up your Dockerfile to install node modules within a container.

Creating a Dockerfile

The Dockerfile serves as a blueprint for your Docker image. It defines the base image, runtime environment, and necessary commands to install dependencies and run your application.

Create a Dockerfile in your project directory with the following content:

# Use an official Node.js runtime as a base image
FROM node:18

# Set the working directory inside the container
WORKDIR /usr/app

# Copy package.json and package-lock.json to the working directory
COPY package*.json ./

# Install node modules inside the Docker container
RUN npm install

# Copy the entire application code into the container
COPY . .

# Show that the port 3000 is available for external connections
EXPOSE 3000

# Define the command to start the application
CMD ["node", "index.js"]

Building the docker

Once your Dockerfile is ready, build your Docker image by converting the instructions into a runnable container image.

Open your terminal and navigate to the project directory containing the Dockerfile. And run the following command:

docker build -t my-node-app .

→ -t my-node-app: Tags your image as "my-node-app" for easy reference.

Running the docker container

With your Docker image built, launch it as a container:

docker run -d -p 3000:3000 \ 
	--name my-running-app  \
    -v $(pwd)/src:/usr/app/src my-node-app

→ d: Runs the container in detached mode (background).

→ p 3000:3000: Maps the container's port 3000 to your host's port 3000.

→ -name my-running-app: Gives your container a recognizable name.

→ -v $(pwd)/src:/usr/app/src: This command mounts the current directory on your host to /usr/app/src inside the container. This allows changes in your local files to be instantly reflected in the container.

Conclusion

Installing node modules in Docker containers is like having a magic box that keeps all your app's tools in one place. This means your app will work the same way no matter where you run it, which is super handy!

It's especially great when you're ready to put your app online because everything stays exactly how you set it up. So whether you're trying to keep your computer clean and tidy, or getting ready to launch your app to the world, Docker is like your trusty sidekick that makes everything easier.